The Car

I had been using a very clean 1984 GTV6 for time trials and HPDEs, and it was modified to the extent that the local inspection stations would allow. The car’s mechanicals and handling were all familiar and it had been dead reliable for over four years of road and track use. Reluctant to take torch to metal on my rust-free California car, the initial approach was to search out an already-prepped car, update and set it up as needed, and get to the driver school in April (2006) with time to spare. My search efforts did turn up a couple of GTV6 race cars, but certain timing and finances didn’t line up (they figured I was new when "budget" and "racing" came out in the same sentence). I finally decided to convert my street/track car the rest of the way and build my own (newbie status confirmed).

Choosing the Class

After reading the SCCA rulebook (actually, many times—those who have seen the GCR will know what I mean), I chose E Production. I had a lot of discussions with folks on where the car might be most competitive and I learned that there is no real consensus. The decision came down to two points:

1. I could modify the car more extensively than in an IT class. After all, isn’t half the fun preparing the car?

2. The more modern fast IT cars were running almost the same times as regionally competitive Production cars that are more highly modified, so it appeared that the GTV6 needed more weight reduction and more engine work than IT rules allowed (my observation as a new driver).

In E Production, the GTV6 is classed as limited prep, but is still allowed a decent increase in cam lift, a compression increase to 10:1, and a minimum weight of 2300 lbs (with driver).

Preparing the Car

Most of the first year’s work was safety equipment related—fire system, battery cutoff switch, fuel cell, and roll cage—but it also included some work to lighten the car.

In getting ready for the cage installation, the glass was removed and interior gutted. Aside from the obvious extra seats and interior panels, it’s amazing how much more weight can come out. A few examples are listed in the table below.

There are also at least 10-15 lbs of extra bolts and miscellaneous brackets that can come out. All told, the car came down to under 2400 lbs the first year (without driver—my weight reduction is the next project).

The basic cage uses 1.5" diameter drawn over mandrel (DOM) steel tubing and is mounted at 8 points. We decided to run the front tubes through the firewall up into the shock towers, and the rears attached inside the cockpit but still tied into the shock towers behind the rear bulkhead.

A NASCAR-style doorbar was installed on the driver side to provide a little extra elbow room and help keep unwanted Miatas out of the cockpit. The cage was stitch welded to the A and B pillars (allowed in production class), as well as over the windshield frame.

The car already had a "Supersport" setup, with 27 mm torsion bars in front and SS coil springs in the rear. The shocks were Koni adjustables. The front swaybar was built from stock car pieces from Speedway Engineering, and the rear was a 3-way adjustable unit from Performatek (www.performatek.com). All bushings except for the lower A-arm had been previously replaced with polyurethane. The only changes made to the suspension were:

1. Replace the 27mm torsion bars with the more stout 33 mm Performatek pieces.

2. Upgrade the rear springs to 225 lb/inch circle track springs using custom-built adjustable spring perches.

Stock front and rear calipers were retained. Brake pads are Carbotech race compound, which have great initial bite and haven’t destroyed rotors. As anyone who has pushed the transaxle cars hard at a place like NHIS may have experienced, boiling brake fluid in the rear calipers is one of their few annoying traits. Upgrading to Motul 600 fluid and keeping a fresh set of pads in the rear helps. A cooling scheme is being devised and will be implemented for the next season.

The exterior of the car just got decals—there was no time to do a complete respray this year, so the original Chestnut Brown stayed. The interior got a couple of coats of SEM Rust-shield, which is easy to shoot, levels quickly, easy to touch up, very durable, and not as expensive as a urethane topcoat system. Body was limited to removing the bumpers, replacing side and rear glass with Lexan, eliminating all plastic and glass lighting (except brake lights), and removing the side skirts. A very cool carbon fiber hood (www.prototypecomposites.com) was recently added to save another 25 pounds.

The engine was mostly stock for the first season. The typical L-Jet tweaks were implemented (rev limit removed, loosen AFM spring), ignition advanced, and a cone filter replaced the original air box. CSC headers were installed with a single race muffler, and the exhaust exits forward of the left rear wheel. While the debate is ongoing as to power gains or losses from these changes, it is clear that the CSC headers did make the single biggest improvement in power. The transaxle got a light unsprung clutch, as well as a rebuild/upgrade to a tightened LSD unit. (Although NHIS Turn 3 smoke shows are cool to watch, they are not good for lap times.)

So the car was finally ready (you can see all the details at www.tuoracing.com)—now it’s off to driver’s school!

Driver’s School

Everyone I talked to couldn’t stress more: Bring crew to school! They couldn’t have been more right. The school alternated between 20-25 minute classroom sessions, a 10 minute gap (usually for hitting the bathroom or getting a drink), and then 20-25 minutes on track. Having someone there to take care of the car was invaluable.

The initial session was follow-the-leader, and then some passing to get used to going through turns side-by-side. The instructors would occasionally come by, tap their helmets, and we were supposed to follow them (that is, try to follow—how can a VW go that fast there?). We got into a series of practice starts, followed by a half-lap race. Everyone started cautiously, not wanting to make mistakes or hit other cars. As the day went on, the drivers became more courageous and it started to feel more like racing—a lot like the better HPDEs when you would hook up with someone nose-to-tail and reel off lap after lap—exhilarating! This was that all over again, but at a much different level (and now I could pass…and be passed!). During the final "mock" races, I traded places several times with a pair of newer RX-7s, and the final stint (five-lap race) had the GTV6 and a newly-built RX-7 well matched the entire time. The car ran flawlessly the entire weekend, though the same wasn’t true for all students. Casualties ranged from blown engines and transmissions to detached wheels and a couple of fender benders. Overall, though, the results were a successful school and the format and instructors were fantastic. I left the two-day school at NHIS with a signed-off logbook and was ready to go racing!

The First Race

The first event was a double regional race at NHIS on a sunny Memorial Day weekend. This would be the real thing—racing for position. Qualifying and the races went just as laid out in school, so it was easy to get into the rhythm of the event. Line up on the false grid at your qualifying spot, enter the track in formation, try not to hit anything on the warm-up lap, and then the rolling start. Ahhh, yes, the starts—more on that later.

During the race, everything the instructors told us turned out to be true. The drivers were faster, more aggressive, and some had a lot less tolerance for novice blunders than the folks in school (we’re not in HPDE anymore, Toto). Nonetheless, we completed three qualifying/practice sessions and two races in great weather, made it out with no scratches to the car, and finished mid-pack in a 30+ car field.

The rest of the season followed similarly to that first weekend. We did a total of eight races split between NHIS and Lime Rock Park. The car held up all year, with only typical maintenance needed. There was no body damage, and no mechanical failures (only one instance of, "But I thought you put gas in it"). The GTV6 drivetrain continues to prove extremely reliable, with the inboard brakes providing the only real nuisance factor (if minor) in the area of cooling and adjusting after pad changes.

This now brings me to one of the most exciting parts of the race: the starts.

The Starts

As many of you already know, SCCA races use a "rolling start" (versus standing starts in F1 or SCCA World Challenge). Initially the most terrifying part of the race, it has become one of the most exciting.

Thirty-five or more cars are formed up side-by-side after a pace lap, approaching start/finish with engines wound up and ready to go, getting the green (usually), and charging into the first turn on cold tires and lots of adrenaline. At first, I could only explain it as the baseball fielding exercise (aka "pepper") on steroids—standing with your back to the fence but having five balls (instead of one) hit at you at once. Catch as many as you can but don’t get hit by the others. It’s amazing how much information comes at you in such a short time. But after a few races it’s equally as amazing how fast you can process that much information and act on it (like seeing the opening where you can grab three or four spots at the start).

Next Season

A few changes are planned in preparing for next season. We are adding a programmable Megasquirt fuel control to replace the L-Jet that has served so well. This, with some fuel system upgrades and a custom cam grind, should add some sorely needed power. A full race motor is in the planning stages, but needs to wait (there’s that budget thing again). The car will be lightened some more, Heim joints are being added, and we are moving to race slicks (instead of the Hoosier DOT radials), which will require a new alignment and pressure setup.

In Closing

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