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Honda calls it quit

In a stunning announcement, Honda is closing the shutters on it's Formula One program. One can only wonder it the Max and Bernie single engine lunacy had an effect, or if this is just another sign of the times.

I hope Button finds a seat next year. Barrichello was probably toast anyway.

Happy Anniversary

Today marks the 4-year anniversary of the first post on this blog.

Man up, Yo.

After reading about it on my favorite bike-blog, Bike Snob NYC, I decided to test the manliness of my blog with Genderanalyzer .

According to the smart computers over at Genderanalyzer, there is a 89% chance that all this is being written by a man.

My other blog, which I share with my wife gets a "likely female" but produces a 50% score. This thing seems pretty accurate...

Dewalt Impact wrench

This thing rocks. On Saturday I installed snow tires on Kathy's car, rotated the tires on my 3/4 truck and swapped wheels on the M3 so I can sell the LTWs. That's 72 lug nuts including 32 that were torqued to 125 Ft/lbs last fall.

The Dewalt just ate it up and asked for more. It can easily remove lugs bolts when the wheels are off the ground. It's got plenty of power and makes quick work of everything I've thrown at it. When reinstalling wheels, the "rocker" trigger is nicely variable so it's easy to snug-up bolts without over torqing them.

That said I also got to use the 18v Snap-on and talk at length with a guy who owns one. As nice as the Dewalt is, the Snap-on is the best tools available. It produces well over 600 ft/lbs when removing fasteners. In fact the Snap-on is the only wrence designed specifically to remove fasteners. The Dewalt and the Milwaukee are both designed to drive-in fastners with the same power that they are removed. The Snap-on produces twice the torque when removing fasteners than when installing which is perfect for automotive applications.

So If you can part with 5-large for a cordless impact wrench, then grab the Snap-on. If your're thinking more like $300, then the Dewalt is a good choice.

of cordless impact wrenches

This is a must-have tool for any open-tracker. I borrowed one at Miller and was shocked at how quickly I swapped all four wheels -- I'm pretty sure it was less than half the time required using a breaker bar.

I've been looking at them ever since and recently decided to get one -- here is what I learned:

1. The biggest, baddest, cordless impact tools out there (Milwaukee 0779, Snap-on CT4850HO) cost ~$500+ and can generate well over 350+ Ft/Lbs when removing fasteners, more than enough for wheel bolts.

2. For about $300 there are a few wrenches that generate 250-300 Ft/Lbs.

3. Below that are wrenches that generate ~100-200 Ft/Lbs and are probably not suitable for wheel bolts.

4. Some vendors sell wrenches that look alike but have very difference performance -- compare model numbers.

I chose a 18v Dewalt, Model DW059k-2, which generates 300 Ft/Lbs and uses the same battery as my cordless drill-driver. I paid $277 (with a case, charger, and two batteries) from Amazon and received free-shipping. I needed to replace the batteries in my drill driver anyway so it was like spending $100 on the wrench. I'll have it in a couple of days and describe what I learn.

Fall Update

I got one more day in after Hastings, a single NASA day at Pueblo. Work and travel conspired to keep me off-track for at last 3 local track days.

Now, with no events until next year it's time to start thinking rebuild. I'd like to fully rebuild both front and rear suspension with new coil-over springs, bars, shocks, chassis reinforcements, and all new bushings. However in light of the current economic condition, maybe I'll scale back a little bit. Other than that, this winter I'd like to weigh the car, remove the air-bag system, and install a removable steering-wheel.

One thing I had to do was replace the battery. The date indicated that it was 4+ years old so I wasn't surprised it died after the car sat a couple of weeks. I replaced it with an Odyssey PC680 -- which is pretty much a big motorcycle battery -- in a really cool battery-box designed by Russ Wiles and available from BimmerHaus in Boulder.

Learn more about the box and battery here

This removes ~25 Lbs from the trunk and I think it changed the rear ride height a little. 2900 Lbs. here I come.

Hastings After Action

Hastings was great. I wrote something about it on my personal blog here

Not discussed there is one of the highlights of the event, the Saturday night "Bacardi Bus" ride. The bus is a modified School bus used to take Corner Workers to the flag stations during events at Hastings. Most of the original seat have ben removed in favor of used furniture -- couches, love-seats, old car seats. Adding to the fun, they are not attached to the bus.

On Saturday nights, after a couple cold, malted beverages, the bus is loaded with unsuspecting drivers and workers, and sent out on track. The driver goes much faster than you would think a school bus would go on a race track.

As you can see from the in-bus photo, we are tracking to the apex in a full-on deluge.

Motorsport Park Hastings

This weekend is a NASA RM event at Motorsport Park Hastings (MPH)? Get it?

It's supposed to be a really good track. It's a bit of a haul -- 5.5 hours says Google Maps.

I've added fixed camber plates increasing negative camber to 2.5 degrees. This should help reduce some of the tire wear i'm seeing with stock camber settings.

1995 M3 Issues

There are a few important maintenance items that are really must-do on a 1995 M3. They are all actually pretty difficult to do but if you don't, and they fail, you will wish you did.

1. Weak Valve Retainers

Early 1995s (prior to 10/95) have improperly heat-treated valve retainers that can fail causing a catastrophic engine failure.

More details here

2. Loose Oil Pump Nut

The nut attaching the drive pulley to the oil pump can come loose causing a total loss of oil pressure and a few seconds later, catastrophic engine failure.

More details here

3. Loose Rear Diff Bolts

The bolts attaching the LSD cover to the carrier may not have had locktite applied properly at the factory allowing bolts to fall out and be ingested by the ring/pinion gears causing catastrophic differential failure.

More details here

So, go check your nuts, bolts and retainers...

Miller Photos

Better late than never.

I finally connected with the photographer from the Miller NASA event. Here are a couple of really nice shots.

Hard to imagine anything cooler than this

More about roll cages

Ranked by importance, my criteria for optimum cage design is

1. A safer cage is better
2. A stiffer cage is better
3. More driver space is better
4. Easier driver egress is better
5. A lighter cage is better

The following series of charts is from a thread on bimmerforum.com about cage design. One of the members did a series of mathematical simulations of a roll cage designs using ProE to build the model and Mechanica to run the simulations. These simulations estimate what happens to a roll cage when a load is applied to one corner. The goal is to understand the stiffness of each cage design and the trade-offs involved in different designs.

This approach has a few weaknesses, primarily the lack of a similar model of the unibody chassis in order to evaluate how the two structures work in concert.

That said, this is really interesting work and bears thorough review.

This first picture shows a basic 6-point rollcage with “X” style door bars, harness bar, and a rear diagonal.

In this simulation, a 500 Lb. upward force is applied to the driver’s A-pillar leg and the strain on the rest of the cage tubes is represented graphically.

Notice how large the windshield and door openings are in this design – probably not good for stiffness.

Here is a second chart showing what happens if you add an A-pillar down-bar, change the driver’s door-bar to allow easier access, add a bar from driver’s shoulder to rear bulkhead, and small upper windshield gussets. The stiffness of the cage increases by over 60% with the addition of only a couple of strategically placed bars.


Here we have added a bar from the A-pillar straight to the floor and dash bar gussets. This is 76% stiffer and weighs only 23 Lbs more then the original design.

All the models so far have used 1.5” .120 wall DOM tubes. What happens when you go to 1.75 .090 wall DOM? Cage weight goes down 2.5% and stiffness goes up 7%.

This chart shows the difference in stiffness between two different A-pillar configurations. The design on the left is about 10% stiffer than the design on the right. Clearly there are trade offs to be made here, as the new A-pillar bar on the left is pretty close to the driver.

Bryan Watts has this design (with an additional gusset) in his E36 M3 and says it doesn’t interfere with driver’s vision at all.

The door bar configuration shown here – typically called “Porsche style because it is derived from the a Porsche GT-3 Cup car – is about as stiff as the stiffest designs and makes entry/exit easier and because they bow outward they provide more room in the drivers “office”.



This chart shows the stiffest design to date without crazy braces in the windshield area. It has a fairly radical A-pillar bar, small roof and dash bar gussets and a roof diagonal all in1.75x.090 DOM.

At this point I’m planning a cage like the stiffest shown above but with either Porsche-style door-bars or with a standard X. Both of options are pretty close to the ultimate in stiffness. The standard X would allow me to keep the windows in the car. Unless you have an enclosed trailer (not in my plans for a few years) then windows are really practical. The Porsche door bars can be made to just fit while keeping the window glass, but removing the door panels (which are pretty thick on the E36).

I will also extend the cage forward from low on the A-pillar bar to connect to the firewall. This provides some additional protection for the drivers feet.

The final key feature I'll add is a jacking tube integrated into the door bars. This creates a reinforced point from which to lift the car. A short "spike" attaches to a floor jack effectvely preventing the car from slipping off the jack.

Pueblo #2

Saturday it was back to Pueblo for the NASA Summer Beach Party Event. The weather was a little cooler than the 95s we had been seeing last week. It was a nice change. The car ran great, no major problems.

I pitted with a large group of BMW drivers who regularly attend NASA events. I met some of them at the BMWCCA School at Pueblo a couple of months ago. It was nice to feel like part of group for the first time. I think many open-track drivers are reluctant to admit new attendees into the clique until they have show some kind of driving proficiency.

The new HeroCam needs a little debugging. The camera eats batteries at a disturbing rate. The Users Guide recommends buying a couple of sets of rechargeable batteries and now I understand why. The camera seems to get about 90 minutes of recording out of a pair of AAAs. The problem is that the SD card holds 56 minutes of video. As a result, I need to install new batteries for every session. Home Depot sells 16 packs of AAAs for about $10. Rechargables are about $16 for 4 and the charger is about $25. So, for a typical track day with 4 sessions, I'd need 8-10 batteries. Call it 10 for $40 + $25 for the charger = $65.

Non-rechargables cost about $6.20 for the same 10 batteries so it takes 10 track days (or 5 weekends) to recoup the cost of the rechargables. I'll do that many next year for sure so I think I'll get the rechargables.

I also need to upgrade the Traqmate software from TraqView to TraqStudio ($199) so I can integrate video with the Traqmate data on a single screen.

Here are a couple of shots of the camera mounted in the car. For forward looking stuff I used the suction cup mount on the inside of the windscreen with the camer mounted updide down.

I also added a mount to the rear of the car using the supplied plastic mount that attaches to the car with a super adhesive. The camera and case weigh only a few ounces so this is actually a pretty rugged mount.

When I actually mounted the camera, I added a little safety wire between the camera and the license plate frame just in case.

This shows the complete camera mounted on the windscreen. The camera is mounted upside-down here and has a setting to record upside-down so I don't have to flip it in post

The picture quality is acceptable and very usable to YouTube and other web publishing. It even looks OK on a big-screen if you are sitting far enough back.

Because of the battery problems I only captured two sessions. I'll add some video here soon.

Carbon Fiber Roll Cages

Read all about it.

Video

I spent most of a day Sunday trying to mount a video system in the car. Being in the video industry I planned the ultimate in-car video system. I have a Sony HVR Z1 U 4:4:4 1080P HD camera looking forward and a Canon XH-A1 1080i HD camera pointing aft. Using our Red ONE 4k camera seemed like overkill.

The problem is that pro- and pro-sumer cameras are large and heavy, each of the HD cams weighs something over 5 pounds and is large enough to make them all but impossible to mount safely in a car without a cage. They won't fit in the rear window becasue they are too tall. I fabed an arm the attaches between the stock head-rest mounts but found it too flexible for even a single camera. Hard braking dropped the point of aim by 6 inches. After a bunch of trial fitting and fabrication, I have decided on another, very different, path.

I gave up on the HD setup and ordered a GoPro HeroCam. $179 + free shipping. It is solid state, light-weight, comes with lots of mounting options and is designed for just this application. Plus it's in a hard plastic case to allow it to be mounted outside the car. Something quite out of the question with someone elses $5k HD cam.

I'll revisit the full 2-screen HD setup when the cage is in.

...and the Big Brown Truck just dropped off a new Nady PMC-2x Intercom so driver and passenger can chat in comfort.

Counting the days till NASA on Saturday -- lots of new things to try.

Chunking Tire

I finally unwrapped my tires from the Miller event. Here's a photo of my passenger front tire showing significant chunking both on the center band and the edges of inner tread block.

This is suprising because the stock suspension lacks enough negative camber for track work. This is confirmed by some significant wear on the outside shoulder of front tires. The opposite side showed very minor chunking -- 2-3 small chunks total.

I'm not sure when this occured -- I suspect it was saturday afternoon. It was really hot, 98 F, and blazing sun, the track was probably close to 120 F. I was pushing pretty hard as well. There was a little push in a couple of corners but nothing out of hand.

I think the centeral nature of the chunking indicates too much air pressure. Except -- you can clearly see the mold line separating the left and right halves of the tread. If the air pressure is really too high wouldn't you see enough wear on the center rib to obliterate the mold line?

Saturday afternoon I dropped pressures and ended up at 35 Lbs hot in front. I guess I'll drop to 33 but I'm concerned about anything that might increase wear on the outside shoulder.

Oil Cooler Project

This morning I found a deal on about half of an E36 M3 Euro oil cooler. A member of the Spec-E36 list offered the oil cooler and lines for $100 -- a smoking deal. I still need the Euro Housing and some mounting hardware to finish the job. I'm not in a particular hurry so I'll keep looking for a cheap used housing if such a thing exists.

Incredibly cool waste of money

Like fighter pilots of WWII open trackers can now display their "kills"

http://www.trackgraphic.com/store/products.aspx

Traqmate Traqdata Adapter

Traqmate offers an expansion port for logging additional digital and analog signals with the Traqmate system. The product, called Traqdata, provides 4 analog, 2 digital, and RPM inputs.

I primarily want to log RPM and oil pressure. I'll also add oil temp and volts since I already have aftermarket gauges and therefore clean sources for these.

The only problem is the damn thing costs $129+shipping.

As you can see from the picture, it appears to be a terminal board connected to a low-density DB-15 connector. The LD DB-15 is not a very common connector type. It has the same number of pins as high-density DB-15 VGA connector but in two rows instead of three. I think the LD DB-15 was used for PC gaming adapters back in the day.

I'm wondering if buying a 10 ft. LD DB-15 cable and a small terminal board would work instead. It would cost about $10, look a lot cleaner and allow me to run the cable from the transmission tunnel near the rear seat where my Traqmate is mounted to the dash area where everything to be monitored is located.

I think I start playing with the input pins this week to see if I can understand what the pin-out is for this is.

E36 Rollcage Design Considerations

I found this picture on bimmerforum.com. It inspired me to begin to document some roll-cage design considerations.

Lets start with the basics. Note how the main hoop is built on boxed foundation blocks called Plinths – the front legs are on similar blocks. This allows the cage to be tack-welded in place, then lowered from the blocks and fully welded, then raised back to the final location. The footers cannot exceed 100SqIn per SCCA regulations.

The rear upper bars attach at the rear bulkhead. This is an area of contention regarding the E36 chassis. One camp advocates connecting the main hoop to the bulkhead claiming that picking up the chassis as high as possible yields the greatest increase in torsional stiffness. The other camp argues that connecting the main hoop with the shock-mounts and therefore the suspension is best. I fall in the former camp. The cage pictured manages to do both. The main hoop is connected to the rear bulkhead and the rear shock mounts are tied into the rear subframe. Nice.

All 8 rear suspension mounting points (4 sub-frame mounts, 2 trailing arm mounts, and 2 rear shock mounts) are all connected. This increases the stiffness of the rear of the chassis. The smaller size of the tubing connecting the rear suspension shows this is not a full tube-frame car. If it were the tubing would be the same size as the main cage.

This cage also uses the construction method known as “super-nodes”. This is when tube intersections (called Nodes) are designed so the all the tubes intersect precisely and the location of intersections is carefully planned so that the maximum number of tubes joins at each intersection.
In the upper foreground a pair of diagonal windshield can be seen. The windshield opening is one of the larges openings on a roll-cage. These diagonal provide a significant increase in stiffness.

This cage has one a really cool feature. It’s a “jack-tube” welded to the door bars at fore/aft balance point and descending through the chassis. It provides a perfect location to lift the car from below. A short spike-like attachment on a floor-jack goes into the tube providing a totally secure method of lifting the car.

Note also how the entire chassis has been seam-welded. This is a technique to stiffen the chassis by adding additional welds to the body and chassis panels. The factory only welds a chassis at a few locations.

Gen-u-wine Redneck style Traqmate mount

June 27, 2008

PR Newswire

Castle Rock, CO – Today Redneck Engineering is proud to announce the first in a long line of low-cost, marginal quality, handmade, paradigm-shifting parts and accessories for hardcore motorsports enthusiasts and people suffering the debilitating effects of Restless Leg Syndrome (RLS).

This amazing new product is years in the making, requiring dozens of man-minutes of labor and the use of state of the art MacBook Air computing power (and of course Microsoft PowerPoint -- what product would exist without PowerPoint?). No expense was spared in it's construction. Only the finest first-cut endangered rain-forest lumber, Bald Eagle feathers, and freshly harvested baby seal pelts are used in the construction of these modern marvels.

Years of double blind testing have shown the 92% of males 21-40 prefer their Traqmate mounted high on the dash where it’s easy to see and access the controls while on track. Additional research shows that 88% of E36 M3s still have the OEM cassette deck. From these data a revolutionary new idea – sure to be compared with such revolutionary ideas as the Wheel, Internal Combustion and the Hula-hoop, was born. As was our catchy slogan "Stick it in your slot".

The mount is a stylish TDK-SAX cassette shell designed to fit in the OEM M3 tape-deck. To this shell is glued a piece of high-tensile strength steel bent to an attractive 90 degree angle. It may appear to be from a Harbor Freight compressed air filter/regulator/oiler set, but this is only a coincedence. The bond between shell and steel, made with state-of-the-art two-part epoxy is impervious to water, sand, and sweat (I think). This durable piece of imported steel is then screwed to the Traqmate's mounting points with screws made of genuine metal. When inserted into the stock tape-deck, it places the Traqmate DU in a great position. It is also easily to remove between sessions so the driver can download data. It is firmly mounted and doesn't move very much.

No animals were harmed in the testing of this product – well wait a minute, there were a bunch of bugs on the grill after driving back from Utah. OK, a few thousand insects were killed, but I doubt anyone will miss them. So, stick it in your slot!

Redneck Engineering is a fictitious company and this is a fictitious product. This is Humor and was not intended to offend Rednecks or Engineers. For more information about humor, go to your local stand-up comedy club.

Press Pool Photos Only -- Fair Use Rights Apply
Traqmate and Cassette Shell (all tape removed). Note the fine metal work on the mount. After a grueling 10 year apprentice program are the finest artisans selected to assemble your Traqmate mount.











Reverse View -- marvel in the quality of the lima-bean colored finish. Notice the aggressive weight reduction.








Without Traqmate























With Traqmate installed -- DIN Cable is router through center console and up through a small slot slot in the punch-out.

Basic Data Analysis

A little detailed analysis courtesy of Traqmate. This graph is a standard Traqmate graph showing Speed vs. Distance. The area of focus in a series of five interconnected corners at Miller Motorsport Park called Demon, Devil, Diablo and Indecision, Precision.

The first three are typically done as a single, double apex corner – a single arc hitting Demon and Diablo and skipping Devil) then a very short straight, then Indecision, a fast right, then Precision, a very late apex tighter right leading onto a long straight. Since Precision is the most important corner in the section, Indecision is sacrificial. However, It’s too long to just throw it away.

The red and blue colors on the graph represent my first and second sessions on the full track. Since these are my first laps on the full track, there is a lot of learning going on as shown.

At the beginning of the chart (7k ft to 7.3k) you can see my speeds from Demon to Diablo were all over the map – ranging from 51mph on the slowest lap to 64 on the fastest. This is natural given that these were my first laps on this configuration and the apex of Demon is blind.
The section from 8k to 8.5k is the turn-in for Indecision to the apex of Precision. In the early laps my speeds were in the 60s, but by the last session I was approaching 80mph. Comfort builds speed.

Note that at the 9k ft. mark, everything lines up again. I’m not sure if it’s due to masterful driving or fear of the concrete wall along the exit of Precision, but those apex speeds sure are consistent.

R-Comp Tars

One thing I learned at Miller is that Khumo MX’s are not R-Compound tires. A few years ago they were among the ultimate track tires even though they carry a treadwear rating of 220. But today there are a slew of sticky new track tires available.

I now have 4 track days and about 800 street miles on the Kuhmos and they are almost half gone (4-5mm remaining of the 7.8mm original depth). This seems to be pretty reasonable wear for the performance they provide.

Because my stock suspension doesn’t have enough negative camber, it causes some extra wear on the outer shoulder of the front tires. Rotating fronts and rears only prolongs the inevitable. While at Miller I also experienced a little chunking on the middle of the outside front tire. This is typically caused by overheating. It was warm there and there are a number of corners that really loads the outside front tire.

Scott is running Nitto NT01s on his 3600 Lb, 400+ HP BMW 335i and recently got 9 track days from his first set. That is really good wear -- on par with what I will get from my Kuhmos. Oh, he’s like 17 seconds a lap (at Miller) faster than me too.

Replacing the Kuhmos with Nittos seems a no-brainer, however there is one more twist. Nitto doesn’t make the NT01 in the 245/40-17 size I use, they do however offer it in a 255/40-17. This is a little wider and a little taller than the Kuhmos. Luckily this is a very small amount and it should fit without any mods. Worst case a 5mm spacer up front.

Size....Tire...Size.....Width...Diameter
Nitto...NT01...255/40...10.35....24.92
Kuhmo...MX.....245/40....9.90....24.80

E36 Track Cars

At the Miller event I was lucky enough to pit with a group of local E36 M3 drivers. Two of them, Gabriele “Gabe” Giese and Jeff Blonder both have well setup street/track M3s. Gabe’s Hellrot 1999 has a TC Kline double-adjustable suspension kit with 700F/900R springs. The 200 in/lb difference between front and rear is more than typical for an E36 where the difference is typically 100 in/lbs. She also runs 255/40-17 tires, which required more an a little rear fender rolling. She describes it as having no understeer – ever.

I spent a lot of the weekend chasing Gabe’s car. She is 2-3 seconds a lap faster than I am and was nice enough to give me lot’s of data about the track.

Her car also has a very unique roll bar set up. It ties in the shock towers and all four sub-frame mounts but doesn’t come any farther forward than the “B” pillars. This is a concession to street use. A full cage can be dangerous on the street as the steel cage bars are really close to the driver’s head. On track the driver’s helmet provides the needed protection, but on the street it’s steel vs. skull.

Gabe uses a RaceTech seat with head restraint, which looks really nice but is just a little narrow for me. I think they offer a wider model as well.

Jeff Blonder's M3 is a supercharged Avus blue 1997. He has added a Eurosport twin-screw supercharger and intercooler kit that he claims produces almost 500HP.

Jeff is more my size and uses a Sparco Evo L seat which fit me really well. It’s now on my short list along with the Recaro SP-G. Jeff’s car also has a custom rollbar, although his doesn’t pick up the subframe mounts like Gabe’s car. He does have the stubs welded to the mounts but they aren’t tied to the bar yet.

The final car was Todd Green’s wicked Cosmos Black 1995 M3. This is a pure track car. It is totally gutted (including the dash, wiring harness, doors, Etc.) It has a sunroof delete (using the infamous E-Bay carbon panel (which looks just fine, thanks)) and a carbon hood. Todd says the car is about 2500 Lbs.

Todd runs 295/30-18 Hoosiers on CCW wheels and a full JRZ suspension. These tires are HUGE and stick out from the car even with front and rear flares.

Although pretty close to stock HP (Cams, CAI, Etc) Todd’s car was mixing it up with the fastest Corvettes in the Time Trial group.

NASA Results

Since I had a transponder in my car, results of the NASA event are available on MyLaps

Introduction to Data Acquisition

My new Traqmate GPS data acquisition system arrived the afternoon before I left for Miller. The system is pretty easy to install. I put the main unit on the transmission tunnel just behind the console. It’s mounted using some strong elastic shock cord and a quick-disconnect hook for easy removal. The Display Unit is mounted to a empty cassette tape shell. The tape fits in the OEM radio and makes a convenient location high in the center of the dash.

One nice feature I used on the drive out to Utah is the “Drive” function. It displays speed and time during road trips. It shows that with my miniature 215/45-17 tires the speedo is only 2 Mph off. I had expected 3-4.

The only problem is that in “Drive” mode it is recording way points. I didn’t realize this and was surprised to discover that on the second lap of the first session the memory filled up and it stopped recording laps. I cleaned it out and used it successfully in the second session.
From a driver development perspective here is what I learned.

The track mapping is really good. It clearly shows when the driver moves off-line to pass, or to avoid other cars. This accuracy allowed me to ID which corners are still troublesome because the lines through them are pretty thick (showing a bunch of different lines. In corners that I had nailed, the lines are thin and sharp. This served to confirm that a lot of corners still needed work, but I already know that.

My second focus is on small segments of the track – specifically segments that lead onto the longest straights. At Miller these corners are “Work Out”, “Precision”, “the Attitudes”, “Tooele Turn”, and “Release” with the last the single most important.

Focusing on segment times allows the driver to understand the relationship between entry speed and exit speed and how they impact segment times. At the same time I looked at 2D loads (Accel/Deccel and Left/Right). When combined, this data shows, how braking and turning impact segment times.

This analysis showed many things

1. I was braking too early for turn 1 (Sunset Bend). This was shown by the fact I was threshold braking then coasting for 10-15 feet before the turn in. Remember Sunset bend at the end of the front straight where top speed is 130+ slowing to 76 at turn in. There is significant trail braking as well as. After the analysis I started braking later and carried the braking much deeper into the corner (almost to the apex on the fastest laps).

2. The Black Rock Hairpin is a tricky corner. It’s a increasing radius deal with a little helpful camber around the outer edge. It can be done a number of ways (single-apex, double-apex, no-apex, etc.) Analysis showed that although the camper on the edge was helpful (+1 Mph), the longer distance negated the advantage so early single apex line was the fastest.

3. “Release”, the corner leading onto the longest straight is a 160 degree banked turn. The best line appears to be a late turn-in (using all the the pit-exit lane) and get on the power just after turn-in. The banking makes exit speed easy to find quickly. The trick to “release” is entry speed. On my fastest lap my segment entry speed was 67 Mph resulting in max speed of 131 on the straight. A segment entry speed just 2mph slower results in a max speed of 126 (a loss of 5 Mph). On my fastest laps I was just tickling the rev limiter at the brake zone.

4. Embarrassingly, my fastest time through turns 1,2,3 (a set of Right-Left-Right sweepers) came on a warm-up lap. I went into 1 a little slow and was flat out through 2 and almost flat through 3. This is much different that my original technique of a little right-foot braking for 2 and a little more left-footed for 3. Each time I over-slowed the car with the right foot in 2, which costs time all the way to 3.

GPS Data Acquisition is a really powerful tool and it will require significant work to use effectively. I really want to see throttle position, brake pressure, and RPMs. This additional data will provide more information about both vehicle and driver performance. I’d also like to log Oil Pressure just in case.

Miller, the afterglow

Well, the three-day event at Miller Motorsport Park is over and both the car and driver returned home in one piece.

The track proved to be everything I had hoped – wide, long, complicated and really challenging to learn, even in three days. The facilities are spectacular, even the restrooms smell good. It is truly a world-class facility rivaling Sears, Laguna, Mid-Ohio, and Atlanta for both the track and for the facility.

The NASA event was pretty well run, not the wild-west shootout that I remember NASA group-4 events were in NASA’s early days. For this event Group-4 was combined with the NASA Time Trial (TT) group. The group might also be called the “Old, rich, erectile dysfunction, Corvette group, as that would more accurately capture it’s essence. The combined ego of the group was illustrated by their custom license plates: “FASTEST”, “TRQZILLA”, “WHYLOSE”, “WAY2FAST”, etc. They all had Corvette Jackets (suitably embroidered with all their manly accomplishment, Corvette hats, Corvette T-Shirts, I’m pretty sure I even saw one guy with Corvette socks.

Mixing non-competitive students from the High-Performance Drivers Education program with competitive drivers hoping to record a best lap-time is a little risky but the reality is that Group-4 is really the domain of Driving Instructors and a couple of racers looking for a little more track time. Since there are no instructors, no discussions of driving technique, and no discussion about the track and it's corners, it's pretty hard to call group-4 drivers education.

With a reasonable amount of wheel-to-wheel racing experience I was pretty comfortable with the last second, at-the-apex, dive-bomb style passing the Corvette drivers seem to prefer. A couple of Group-4 students and a couple of instructors were much less comfortable. After a couple of stern warnings from NASA officials (read: threats to send ALL the Corvette drivers home immediately) things got a little better. The issue was finally addressed when the entire Time Trial group was combined with one of the racing groups. This left those of us in Group-4 a little lonely, I mean it’s a 4.5 mile track and with the departure of the Corvettes there were only about 20 cars. I did one entire 30 Min. session without seeing another car. It was actually really nice to be rid of the geriatric penis car group.

Lessons learned at Miller:

The car is going to require significant development to really be fast. In this era of high-horsepower turbo cars (and living and racing at over 5,000 ft., a stock E36 M3 is a bit of a knife in a gun fight – hell, I got passed by a damn Mini in one session.

The upside of the weekend is I got to take a long look at three very well-developed E36 M3s and have a better feel for what it will take. Two were track-day cars and third was a race car. The Track-day cars were exactly with what I want to do in the short term and the race car is what I ultimately get to. I'll detail each car in a future entry.

Addressing body roll

That's sure is a lot of body roll. In this photo, taken just before the apex of turn 10, the car is generating about 1g of lateral acceleration and the body is rolling about 5 degrees. This is described as 5degrees/g.

This is too much roll for the Mac-strut front suspension of the E36 M3.

When the front of a Mac-strut car rolls, the outside (loaded) strut looses camber as it compresses. This reduces grip just when you need it most. Reducing body roll keeps the suspension in the optimum position and maintains the largest amount of negative camber.

Body roll is reduced using a combination of springs and anti-sway bars.


Note how little roll is shown in the photo below of another E36 M3 with large sway bars.

Photos taken by one of the corner workers at the BMWCCA event.

Reducing body roll and preserving negative camber are among the top requirements for selecting the replacement suspension system.

BMW Club Driving School

Last weekend was my first driving event in the M3. It was a BMW Club Driving School at Pueblo Motorsports Park. Everything went well. The car was reliable, easy to drive, and fairly fast. It's a little slow to turn in - not surprising since it still as a street alignment.

From a driving perspective, I did pretty well. A little rusty perhaps, but not too bad. I had a great time.

I just signed up for a NASA event at Miller Motorsports Park near Salt Lake City. It's a long haul from Denver but it's a three day event and Miller is a track I have wanted to drive since it opened. It's unusual in that its 4.5 miles long and have 23 corners. (that about twice the typical track).

Thanks to YouTube I've been mentally lapping the track for the last few days. Here is the clip I use most often.



I also hope to have a Traqmate Data Acquisition system in the car in time for the event.

All Jacked Up

The thought of lifting my 90+ pound low-profile, high-lift 3 ton floorjack in and out the trunk of the M3 at track events was just too much to bear so I purchased a 3000 Lb aluminium racing jack from Sears. It weights about 26 Lbs and has cool LED lights set into the bottom of the lifting plate so it lights up the bottom of the car right where the jack will start lifting.

Lights On














Lights Off




























Finally a place to put all those stickers collecting in my toolbox.

Flags -- Rear Side

Flags -- Rear Side
Originally uploaded by Ren Finley

Flags -- Front Quarter

Flags -- Front Quarter
Originally uploaded by Ren Finley

Front end finished. Do Not put the car into the sun until ALL the bubbles have been worked out. The sun seems to harden the stickers within an hour.

Flag Installation

Flag Installation
Originally uploaded by Ren Finley

Installing the top-rear section.

Flag Installation

Flag Installation
Originally uploaded by Ren Finley

Installing the flags, I cut the graphic into manageable pieces when covering complex curves.

Before Installing the Flags

Before Installing the Flags
Originally uploaded by Ren Finley

Here is the car before installing the flags

BMW Motorsport Flags

I have always liked the BMW Motorsport colored "corner-flags" that originally came on the 1995 M3 CSL (or Lightweight).


















I was thinking about ordering a set from Turner Motorsports for $159 until I found them on eBay. I won an auction for $85 shipped. They are custom made by iZoomGraphics, a well known supplier of Autocross number packages.

Brake Photos

A week late due to the trouble with the ABS ring but the brakes are now done. I rebuilt everything and ran a full can of Super-Blue fluid through with a pressure bleeder while pumping the pedal.

Here is the drivers front hub with damaged ABS ring along side the new hub. Note different style ABS ring on the new hub. This was a $150 mistake.














Turner was back-ordered on 46mm sockets to remove the front wheel-nut. The only thing I could find locally was a 46mm impact socket. I ground it down from 68.4mm OD to 64mm to fit into the front hub. It took over an hour to modify.














Front caliper during rebuild. Shown here are the old and new guide rods, old and new seals, brake caliper, piston, snap-ring pliers and Wurth Copper anti-sieze.














Here is the finished front corner with new pads, rotor, seals and lines (and in this case a new hub)

Note to self...

Be very careful removing backing plates with a rotary cutter -- it really easy to nick the ABS ring on the front hub ruining it forever.

Guess how I know....

So the damaged ABS ring means a delay to order a new hub the the 46mm socket to remove it.

I did cave a buy the window motor locally. I simply couldn't wait another 3-4 weeks to drive the car.

Bitter Disappointment

I arrived home to find my shipment from Bimmerworld is missing the rear rotors. Damn. Oh well, I'll work on the window motor instead.

Shit, the previous owner shipped me the passenger side motor instead of the drivers side that I need. Strike two.

Brake upgrades for the E36 M3

Open-track events are really hard on brakes, much harder than any street driving. It is common for rotor temps to exceed 1000 degrees F. Temps this high can shatter rotors, melt brake pads and boil brake fluid. Losing your brakes is bad, losing your brakes on the track is infinitely worse.

The first thing to consider is the capability of the stock brake system. Things like rotor size (both diameter and thickness), number of pistons, and system design should be considered.

After much research it appears the the stock E36 M3 brake system is robust enough for open-track use. Especially considering that here in Denver, the car is down on power due to altitude. Less power = less speed = less work for the brakes compared to sea-level. If I were building a car to compete nationally I would not consider altitude in the selection process.

Now that I have decided to stick with the stock system we can look at each part of the system and evaluate it's performance and explore alternatives.

The first and most important choice is the brake pad. This is by far the most important choice regarding track braking systems.

Things to consider in selecting a track brake pad

1. Cost -- you will be buying lots of these
2. Heat range -- Each pad has a preferred operating temp range, this needs to match your predicted use.
3. Friction -- Some pads work only with very sticky tires and will quickly destroy other tires.
4. Wheel damage -- At least one pad (Hawk Blue) creates a dust that when mixed with water forms a black/grey coating that is impossible to get off your wheels -- ask me how I know.

After discussions with a number of vendors and racers, I chose the highly recommended Performance Friction Carbon Metallic pads in their "01" compound. Here is what PF says about this compound:

01 is one of the most advanced race compounds in the PFC's arsenal, and has become the standard by which all brake pads are judged. It has good initial bite, with very little torque rise with temperature. At the end of the stop, 01 Compound has less torque scatter for improved modulation with excellent release. 01 Compound has good disc conditioning properties with low wear. 01 Compound is one of PFC’s most popular race compounds and wins more World and National Championships annually than any other brake pad on the market.

Now that we have our pads we can look at the rotors, the stock front M3 rotors are 315mm x 28mm, cast iron and vented. These are fairly large for a 3000lb car and reflect the performance oriented nature of the M3. While the OEM rotors are good, there are a couple of upgrades available including floating rotors from the European M3 or aftermarket floating rotors.

Floating rotors are the sime size and shape as the stock units but have one significant difference -- the disk (where the pads clamp) and the hub (the attaches to the suspension) are separate and connected in a way that lets the disk move laterally as it heats and cools.

Floating rotors provide a number of advantages:

1. It allows the disk to center between the pads as they clamp down
2. It reduces the amount of heat that is transfered to the wheel hub and wheel bearings.
3. The hub of a floating rotor can be made from aluminum reducing the weight when compared with a solid iron rotor.
4. Some aftermarket rotors allow the actual disk to be replaced while keeping the hub, reducing the cost of replacement.

A step up from the Euro Floating rotors are aftermarket floating rotors -- these are generally considered racing parts because the use different hardware to attach the disk to the hub. The hardware allows the disk to be removed and can require more maintenance that solid or Euro rotors. Imagine having to torque the rotor bolts every 5k miles on a street car. Not a good thing.

Both Racing Brake and Performance Friction offer stock-sized full floating disks for the E36 M3.

I made my choice based on primarily on long-term cost. I ordered Performance Friction front rotors -- PF doesn't make a rear set up so I chose to go with stock rotors out back. Since the front brakes do 70% of the work (and generate 70% of the heat) this shouldn't be a problem.

The PFs rotors are more expensive than the Euro rotors ($530 vs $330) but PF replacement disks are about the same price ($350) as the Euro rotors so long term the costs are comparable.

Now we can optimize the rest of the braking system. This will entail completely rebuilding all four calipers with new seals and dust boots. I will also be replacing the "guide rods" and rubber bushings with new brass rods with brass bushings. This will keep the two halves of the caliper in better alignment as they clamp down on the rotor.

I am also replacing all 6 brake lines with braided stainless. This is as much about safety as performance. the new lines will have little performance advantage but will make the driver more confident knoing the lines are new and not 13 years old.

When complete I will flush the entire system (including the ABS sytem) with Ate Super Blue (or alternately Type 200 Gold) fluid.

With shipping this is about $1400 for everything front and rear from Bimmerworld. I originally planned on replacing all four corners with the Bimmerworld Wilwood Stage III kit with costs about $3300 + 200 extra for the PF 01 Pads.

Initial testing will show if the investment in the OEM system was worth it or if I have to upgrade to the Wilwood kit anyway. Time will tell.

Finally

I arrived home to find the new drivers window motor has finally arrived from the previous owner exactly one month after buying the car. I'm a little disappointed to find the title was not in the package.

I'll add the installation of the motor to list of work I am planning for Saturday.

New wheelz and tarz

Last night the brown truck delivered 118s new track shoes from the Tire Rack.

They are a set of four 17x8.5 Kosei K1 wheels shod with 245/40 Kuhmo MX tires. Since these are dedicated track wheels I also got a set of "Wheel Totes" to carry them back and forth to the track without getting brake dust everywhere.

Note the cool E36 M3 BFG banner. It only took 10 years to get a car to match my banner.

Done deal

The deal is done and I have a new track car called "118". I drove it all the way back from St Louis. Woo Hoo!

This is the 118th US spec M3 made. It was produced in March of 1994.

As with all older cars, it needs a couple of things. First is a new drivers window motor -- it failed as I was picking up the car. The second is a set of proper tires. Some moron installed 215/45-17 on the 7.5 and 8.5 in wheels. It should have either 235/45 (as it came from the factory) or 225/45 front and 245/40 rears.

Wow, that was fast

I think I have found a car. I found a clean well maintained 1995 M3 in St Louis, and am flying there today to look at it. Assuing all goes well I think I'll drive it home.

Here are a couple of pics from Ebay.


I'll update when the deal is done.

It's gone... moving on.

After 8 years of ownership, I reluctantly let the 540i M-Sport go yesterday. As I type this I am waiting for someone to come pick up my go-kart. Selling one's toys is always a little sad. However, the up side is that I am replacing everything with a 90% track focused car.

I've been shopping for the last few days and have narrowed the list to about 8 cars.

From most to least expensive

Lotus Exige
Porsche 996
BMW E46 M3
BMW 135
Evo
BMW E36 M3
Spec 944
Spec E30
Spec Miata

My focus is really on the second half of the list. I once heard that you shouldn't track a car you can't roll up into a ball and not cry about. That pretty much limits me to the second half of the list.

Selection criteria:

Streetable (at least for the first year)
Potential for serious speed
Reasonable maintenance (time and cost)

Sold: 1995 BMW 540i M-Sport Dinan Supercharged

93k mile Arctic Silver with Light Silver-Gray interior. A genuine M-Sport with EDC shocks, Servotronic steering, 6 Speed manual, ///M Badges, Etc.

Enhanced with a full Stage IV Dinan-5 package (Supercharger, cams, suspension, exhaust and big brake kit). 18” M-Parallels. Featured in Bimmer magazine.

Certified Carfax, many new parts, priced to sell quickly.

Location: Castle Rock, CO


More info and photos here:

http://web.mac.com/ren.finley/M_Sport/540i_M_Sport_for_Sale.html