We bought an old stock car | ASA tube-frame racer

Update by J.G. Pasterjak to the American Speed Association Stock Car project car
Jan 9, 2022

Can a decommissioned oval-track car really work for sports car racing? We aim to find out. We just bought one.

First, the influencer on this one: our old pal Jack Higginbotham. In late 2020, he started to share details on his own build, a 1967 Camaro body perched atop an old ASA stock car chassis.

When he bought his project, however, it actually came with two chassis–and he was looking to free up some shop space.

Well, we solved that storage problem for him by trading a small handful of folding money for a large pile of parts and that rolling chassis.

So, just what the hell did we buy?

First, some quick stock car history.

Through the late 1990s and early oughts, a stock car sanctioning body called the American Speed Association adopted a ruleset that specified a highly regulated chassis powered by a sealed, 460-ish-horsepower Chevy LS1 using fuel injection and a dry-sump oiling system.

ASA wasn’t a NASCAR Cup-level deal, but the list of ASA champions, which includes names like Mark Martin, Dick Trickle and Rusty Wallace, certainly shows that the racing offered a great deal of pedigree. National TV put those drivers before a lot of eyes.

ASA had been around since the late 1960s and brought a lot of modern technology to stock car racing. It was among the first major stock car sanctioning bodies to adopt things like fuel injection, spec chassis as well as V6 powerplants.

But as per the group’s Wikipedia entry, ASA moved from national to local-only events in 2004 and then went quiet about 10 years later.

Remember what we said a few paragraphs earlier about spec chassis? From 1992 through 2004, Howe Race Engineering built all of the center sections found in ASA racing.

The center section basically included the driver compartment and roll cage. Those center sections would then be sold to an approved builder who add front and rear clips plus the series-approved parts needed to complete the car.

According to Howe, our chassis, ASA0404, is the 432nd produced of 444 total. It was built in late 2003 and then sold to Lefthander Chassis.

Based on the subframe and suspension configuration, it does resemble other cars that have been positively identified as coming from Lefthander, so we’re pretty confident they’re the builder. We’ve reached out to Lefthander for confirmation and whatever other info they could provide us with, but they were closed for the holidays so we haven’t heard back just yet.

No matter the builder, all of these ASA cars use what’s called a perimeter chassis: The center section has a cage that encloses the entire passenger compartment while parallel frame rails run along both sides of the car and both the front and rear clips are symmetrical.

Now, although the basic skeleton of the car may be symmetrical, some concessions have been made to optimize the cars for the fact that they were really only designed to turn left.

In the case of our car, the right suspension lower attachment points are a bit further inward, and the lower control arms are longer than the left. Different spindles are used on the left and right side of the car.

On the drive home from retrieving our new car, we stopped in Jacksonville, Florida, to visit legendary tube-frame GT builder and driver Tommy Riggins. He pointed out a couple other subtle differences that facilitated turns to the left–like the fact that the mounts for accessories, like the battery tray and oil tank, are placed on the left side of the chassis.

The good news, of course, is that all of this stuff is easily correctible to optimize it to turn both directions, as the chassis of the car is little more than a huge Erector Set. A bit of cutting and welding puts mounts and pickup points exactly where you want them, and the spacious tubular skeleton provides endless room for activities.

So that’s where we are at the moment.

Our email outbox is full of inquiries sent to chassis constructors, parts suppliers and engine builders as we try to track down more info about our car–both from a journalistic and mechanical perspective.

Once folks start getting back to their computers in earnest, we hope to start filling notebooks with info that will help guide our build. After this initial research, we hope to start actual wrench work in the spring. We’d love to have it ready for testing around Christmas 2022 with an eye on the 2023 SCCA Time Trials Nationals in May as our first major event.

In the meantime, here’s a look at some of the bits and pieces that we recently dragged home.

The best place to pick up a project car is an abandoned building, right?

First stop on the way home, Riggins Engineering, where Tommy Riggins has built SCCA- and IMSA-winning tube-frame GT cars for the better part of four decades. He gave our car a thumbs-up, and he’ll be helping out on the project along the way.

Once we got the car into our shop, we got a feel for the proportions. It’s a substantial car, but the tube frame makes everything easily accessible.

First order of business, remove the funk from years of storage. Some CRC Parts Cleaner and Degreaser and a quick pressure washing got rid of the grime and let us start the project out cleanly.

Our car was originally configured to turn left: Check out the longer right-side lower control arm and asymmetric knuckles. Also notice how the right-side steering rack bellows is compressed more than the left side, showing that the rack is positioned primarily for left turns. Squaring up the front suspension will likely be our most ambitious bit of fabrication.

The right-front suspension features a chain so you can lock up your ASA car when you take it to school.

Some good-looking welds on this steering arm. We’re figuring that this car’s last race saw some drama, or someone hastily constructed a replacement to just move the car around.

That’s what the steering arms are supposed to look like. Many of the parts need a good bath and maybe some powdercoating, but the bones look good.

Good news, the right-rear axle has some negative camber. On solid axles, you can install cambered ends and axle shafts with a rounded cut to drive the wheels. Negative camber is our friend.

Bad news, the left-rear axle has positive camber. Well, not completely bad news, because we should just be able to swap out the axle end for a negatively cambered one. The good news is both our axle shafts have the correct cut to accept cambered adapters.

The rear Panhard bar is externally adjustable. In all likelihood, we’ll swap this out for a Watts linkage, however, to keep that axle centered during motion.

This Winters quick-change rear features an additional drive gear set that allows final drive ratios to be swapped in a matter of minutes. We’re not sure what type of differential lies within (probably some sort of locker), but we’ll be tearing into the rear before too long.

This appears to be some sort of high-tech tuned mass damper affixed to the chassis.

Here you can see the different mounting points for the rear of the front trailing arms. These may need to be made symmetrical, or maybe not. Some suspension modeling should help us figure that out pretty easily.

The bottom of the steering rack appears to have been machined by the earth a bit. It’s not showing any gears, though, so it’s probably fine.

The right-rear shock also features external preload adjustment. Before operating, you have to say “She’s runnin’ a little loose. We oughtta tighten ’er up.”

Front suspension has lots of adjustment for caster, camber and anti-dive.

Left-front suspension is tuned for positive camber, but the upper mounting locations and symmetrical side to side.

Interior features include a clutch pedal stuck way over to the left, and a cartoonishly large three-spoke steering wheel with a tiny pad in the center like a carnival bumper car. You know, for safety.

If anyone can tell us anything about the Borg-Warner transmission, we’re all ears. What we know is it’s a Borg-Warner transmissions and… well that’s about it.

We have springs for days. Hopefully some of them are suitable for road course use.

The dry-sump tank has a thing on top that we don’t know what it is, and a 110v plug coming out of it. We’re assuming the plug is either for a preheater or a priming pump of some sort. Any help on that thing on top is appreciated.

Lots of lots of boxes of LS parts from before anyone outside of Michigan knew who Tom Brady was.

This LS1 block uses the internal oil pump to provide flow and pressure, and an external pump to scavenge the oil from the dry sump system. It came without any rotating assembly like crank, rods and pistons, so we’re figuring out that part as well.

This time next year chassis No. 0404 should be turning its first laps on a road course. Wish us luck and watch for more updates.

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