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Starting at the End Apr 4, 2007

Turns out the Bilsteins that were already installed on the car were the exact same part numbers as the ones we're putting in. We'd feel worse about this if dampers weren't a wear item. New for the win. Our project BMW came pre-equipped with a useless (to us) 4.10 open diff, and we decided that mounting the new rear anti-roll bar would be easier with no differentials in the way. This was as good a time as any to perform the swap to our class-legal 3.73 OEM limited-slip diff. Brake pads of unknown origin and questionable usefulness were replaced with Carbotech pads. For maximum efficiency and some unintentional bling, we installed a set of Carbotech-sourced brake rotors. We had to swap the vehicle speed sensor from the 4:10 diff to the 3:73 because the plug shape was different. Per seems to want to eat the sensor.

With most of the interior work completed, it was time to start swapping out the parts that you can't see with the wheels on. The bulk of the work we had to do involved the rear suspension on the car, so we decided to start with the back. Our box of goodies included springs, dampers, anti-roll bars, brake pads and rotors, and an OEM limited-slip differential.

Spec E30 rules dictate exactly what Bilstein dampers are legal (Bilstein Sport P36-0335 or P30-0334 for the front, and B36-2027 for the rear). Ireland Engineering makes some nice upper mounts for these units, so we installed these along with the dampers (these are currently on sale for $75).

The springs are also specified by the rules as H&R Race Springs part number 50404-88. The nice thing about race springs is that they're shorter than the OEM units, so the cute little coil beehives popped right in to place without any spring compression struggles.

Our BMW 325is came with an open 4:10 differential from a 318 already installed. The class rules require that we run a 3:73 OEM limited-slip differential, which will be better for our needs anyway. Since we had to replace the rear differential at some point and since the rear anti-roll bar is situated above said differential, it made sense to pull the diff, install the rear anti-roll bar and then install the new diff.

While Per wrestled with the diff, Scott swapped the generic-looking brake gear for some trackworthy pads and rotors sourced from Carbotech. Once the diff was out of the way we installed the Bilsteins and the rear anti-roll bar, which required a bit of drilling since the Ireland Engineering brackets have reinforcement backing plates that mount into the trunk. It's a much stiffer bar, and you wouldn't want it tearing through the OEM mounts under load.

The rear diff went in with a pretty standard amount of stubbornness for a huge lump of iron, but at the end of the day we had a Spec E30 that was moving under its own power again. Also, it's riding kind of low in the back right now. The front suspension and brakes are next on the list. 

Back to the Front Apr 17, 2007

Some tin snips and a lot of flexing eventually removed the heat-trapping brake dust shields A camber plate from Ireland Engineering should give us a bit more camber, and it replaces the worm OEM rubber units. Chris goes to town with the 20-inch breaker bar Unbolting the lower suspension arms from the chassis allowed us to get the stock anti-roll bar out from under the car. The Ireland Engineering anti-roll bar endlinks are Heim-jointed goodness.

With the Spec E30 looking quite goofy dragging its butt around on race springs, we figured it was only decent to upgrade the front as well. As was the case with the rear, new Bilsteins, H&R springs and brake discs were on the list. While this end didn't contain the joys of a big honking differential swap, we did have to get physical with some stubborn dust shields and muscle the strut tower bar into place.

The biggest difficulty proved to be the anti-roll bar, specifically its removal. We had to unbolt the lower suspension arms from the chassis in order to free it from its happy home and get it free of the car; the new bar slid into place, and after a bit of heaving and hoing we got the lower suspension arms back in place and bolted back up.

Swapping the Bilstein dampers into the OEM cartridges was easy. We took the time to brush and vacuum away some of the packed sand-like gunk that had accumulated in the bottom spring perches.

The Ireland Engineering camber plates don't allow for much adjustment in the stock damper holes, but apparently some racers go down to two adjustment bolts to gain a bit more leeway. We'll start with the four bolts and see if we really need to go any further.

As in the rear, some Carbotech pads and brake rotors were a simple swap. When everything was put back together we bedded the pads in, and the stopping power is greatly improved over whatever mystery pads were on there before. Good brakes make us happy.

Our last component on this day was the Ireland Engineering strut tower bar. It was oh so close to sliding right on, and with a bit of persuasion it notched onto the top bolts of the front struts. 

Spec E30 Debut Looms Jun 18, 2007

Our local hardware store had some heavy duty nylon tow strap that should serve us well if the need arises Who needs a tach? This Brockway Engineering sequential shift light will give us plenty of warning on when to change gears. We mounted the kill switch close to the windshield on the outside of the car near the under-hood battery terminal. Some Goodridge braided stainless steel lines firm up the pedal and get rid of the questionably old rubber lines.

With the BMW Spec E30's debut at the NASA Hyperfest at Summit Point only a few days away, we're taking care of some last-minute preparation items. This past weekend we installed the fire system, a kill switch, some Goodridge brake lines and ATE Super Blue racing fluid. We also mounted up a sequential shift light, but we don't yet have it working, so look for more on that once we've got a good tach signal.

The Brockway Engineering S100 sequential shift light didn't like being hooked up directly to the coil, but we found the all-black tach signal wire going into the instrument cluster and spliced into the signal there. Seems to be working like a charm, although we've got to get it out on the road and fiddle with the shift point; we're not convinced that the E30 is sending the logical three signals per revolution to the tach, it seems to be getting to the "redline" very early. This Brockway unit is pretty sweet, and it'll help us pretend that our Spec E30 is a BMW Sauber F1 car.

If you're heading out to the HyperFest be sure to watch for us, and feel free to drop by the Paul Reed Smith tent where Gary will have the booth set up. Scott will either be by the tent or in the paddock with the BMW. Wish us luck! 

Not that fast, and only a little broken Jun 27, 2007

Thanks to euroimage.us for the great on-track photo.

Project Spec E30 made its debut this past weekend at the NASA Mid-Atlantic Hyperfest at Summit Point in West Virginia. Viewed as a shakedown, it was a big success. Of course, once we hit the track we’re as eager to win as anyone, and that wasn’t in the cards for us this weekend.

This was Scott’s first race weekend in a rear-wheel drive racecar, so there was a bit of a learning curve but the E30 was really very easy to drive at speed. On the few instances where the tail came out it was because we were doing something at full throttle in second gear. It never got scary, and was generally easily corrected. We had one off during qualifying on Sunday when we tried to brake a little too late going into turn one, but it was a simple agricultural excursion under full control when the corner just wasn’t going to happen for the amount of grip available.

Our first-ever session in the car, Saturday practice, resulted in a 1:36.089 fastest lap. By comparison, Vic Hall turned a 1:28.951 in his Spec E30. Yowch.

Unfortunately, we seemed to be a bit down on power, particularly compared to the front runners. We’ll need to get our car to a dyno and try some of the allowed bolt-on modifications to bring our straight line speed up to par. You can only push the gas pedal so hard before Mr. Scott reports that the engines can give no more than that, captain.

With a hair more familiarity with the car on the course, we qualified as second faster with a 1:35.088 for Saturday’s race. The brakes were holding up beautifully, and they seemed to be the only area in which we had some advantage over a few of the other cars on course.

At their full tread depth, our spec Toyos were a little less spec than the rest. Shaved tires were all the rage in the paddock for dry weather, and our attempt to save some bucks by doing the shaving ourselves the old fashioned way wasn’t helping us in the traction department. Still, it’s always nice to have an excuse in your pocket. We also installed fresh spark plugs, as our BMW still seems to enjoy fouling the plugs. We used carb cleaner to clear up the idle air control valve, a possible culprit.

In Saturday’s race, following a rather jumbled starting lineup, we did a lot of mirror watching for faster 944 Turbos and much quicker cars that got gridded behind us for the rolling start. We turned a 1:35.476 and finished 16th out of 19 cars in our class.

Because of a fluid leak, we cut the power steering belt on Sunday. In theory this would free up a few ponies, and we were down to a 1:34.712 in practice on Sunday morning. With a certain level of trust in the car, we were pushing harder in some key turns.

We found another tenth in qualifying on Sunday by really pushing our braking zones. A 1:34.608 had us 14th out of the 15 Spec E30s in the session. Pole was a 1:29.536 by Jonathan Allen. Five seconds off the leader is better than seven seconds, but it’s still a damn lot of seconds over a single lap.

In Sunday’s race, things were going well enough; we’d picked up a few spots at the start and were trying to get close enough to a fellow Spec E30 for a pass while dealing with the lapping Sports Racers and 944 SuperCups. When braking hard into Turn 5 something went awry, and when we got back on the gas we had very poor acceleration. We pulled off line and tried figuring out what was going on.

The engine seemed properly connected to the throttle, was making the right noises and seemed to have a linear throttle, but full whomp felt like about 1/10th whomp. The parking brake had not mysteriously engaged. Nothing felt or sounded broken. We just didn’t have any get up and go. As we headed for the pits, the drag got worse, requiring a downshift to second to keep momentum. Something smelled hot, so we stopped by a fire extinguisher in the pits and asked a friendly bystander to confirm that we weren’t on fire. He said the rear brakes were smoking a lot, but no flames, so we decided to head for our paddock spot.

Getting to the paddock required all the thrust that first gear could muster. The rear brakes were clamped down hard. We parked, changed out of our driver’s suit, downed some water and went to see if we could figure out what was going on. On start-up, the car behaved normally, the rear brakes were fine and we were particularly confused. Also, we seem to have a wicked transmission fluid leak, so we’ll have to get dirty figuring that one out, too.

Our fastest race lap was a 1:34.613, pretty consistent with our qualifying time. Obviously, we’ve got some work to do in the power department, and we’ll have to chase down some braking demons. It wasn’t a record-shattering debut, but the Spec E30 enjoyed a good shakedown, revealed a few problems and still drove itself on to the trailer at the end of the weekend with no visible damage. 

MISSING: Some Horses from the Spec E30 Ranch Aug 30, 2007

Going full throttle indoors always feels weird to us.

We took Project Spec E30 down the road to the Dynojet dyno at Projekt7 on Tuesday, and our suspicion that we were down on horsepower a bit at the HyperFest was confirmed.

From what we’ve seen, most healthy Spec E30s make in the low to mid 150-horsepower range, and those on the low end find themselves in the mid 140s. Our baseline was 134-135 horsepower, and after switching out the stock MAF and filter box with a different MAF and an aftermarket cone filter, we saw a peak of 136 horses.

The tailpipe sniffer told the real story, as our car is going Bill Gates rich at 5000 rpm. The car is leaving for the NASA Championships soon, so we’re going to do some last-minute diagnosing with Rennie Bryant of Redline BMW on Saturday in the hopes of getting the most out of the car at Mid-Ohio.