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Unread 09-20-2013, 02:23 PM
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Fair! Fair! is offline
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Default Vorshlag BMW E36 LS1 "ST2 Build"

Note - this forum build thread is posted to concurrently on 4 forums, including here at Vorshlag.
Project Kick-off, September 17, 2013: Been a while since I kicked off a new BMW build project thread, as we don't show many of the turn-key builds we do here at Vorshlag. But this one is different and should be fun to watch as it goes together. We bought a 1992 BMW 325is coupe a while back and it is finally at Vorshlag about to get the LS1 engine swap and some other race prep it needs. We're building this car around NASA's ST2/TT2 classes, and it will be caged, flared, and LS1 V8 powered.

The purpose of this build thread is to show a behind the scenes look at how we do a turn-key E36 LS1 race car. We intend to eventually sell this car, as happens with everyone's car build eventually, so it will also document the build for the future owner. As with all of our 2013+ forum build threads, you can click on almost any picture for a higher resolution image. With a photographer like Brandon on staff we have show off the goods.

We had an E36 M3 front end on this car, but the seller reneged and now it has no bumper cover at all

We bought this particular E36 example a while back from a Texas seller, and it was running and driving - but just barely. The previous owner had bought it with a blown head gasket, then did some somewhat shoddy repairs to get it running again. At least he was honest about it (and I knew what to look for). After a new head gasket and liberal use of JB weld to fill cracks in the cylinder head, he got it to technically "run" but after just a few days of driving it was puking fluid once again and the motor was done. You see, once a BMW straight 6 engine overheats once, it is NEVER right again. The overheating often warps the head, or the head itself develops cracks, or both - this is because it has such a loooooong engine layout. Without major machine work to the block, head and internals, and a significant cash infusion, the original motor is pretty much as good as a lump of coal.

Luckily we have a great fix for that: an all aluminum 400 hp LS1 V8!

Long Running Debate: Street Car or Race Car?

E36 LS1 swap cars can work very well as beastly daily driven street cars, or you can add big tires and a cage and make them into great race cars. We've done both kinds of builds and this car was a candidate that could have gone either way. We had started it as a street car build, but switched to a race car shortly after coming back from the 2013 NASA National Championships.

Left: This LS1 powered 4 door E36 M3 has air conditioning and is a beautiful daily driver: Right: This LS1 coupe became a race car

Personally, I went back and forth with the direction of this build, since it was going to be a car built "on spec" that would likely be sold in 2014. Each type of build had its merits, and each would be attractive to totally different types of buyers. We had started on the street car option and had Allsheer Interiors recover the stock door and rear interior panels in new BMW sourced. 2-toned leather, and their work was flawless. The interior work was so good I almost stuck with the street car build, but the rest of the car just needed too much work to be in perfect condition: the carpet had a "heel" hole in it, the headliner was sagging, and most of the weather stripping needed replacement. And the car sat outside at my house for a few months (as our both shop and my home shop were full of customer cars rotating into and out of our main shop); it sat under a tree and the sap and crud really did a number on the weather seals and OEM paint, which wasn't great to begin with. But it had a straight body with zero rust or damage. So...

I knew pretty early on that we were going to have to repaint the whole car. Heritage Collision is going to do the paint work (they painted our E46 330, McCall's Z3 LS1, and the front end on our TT3 Mustang). And since they are going to be in there, and we already have a white 4 door M3 street car being built for another customer, we decided to go Full Retar.... I mean Full Race Car on this one.

The goal is to have this car stripped, caged and flared. Then take it to Heritage and have them paint the interior, under the hood, and exterior back in a bright white (probably not the OEM off white that is Alpine White 3). The exterior will be 2-stage but the interior, cage and underhood will be single stage. We have another E36 candidate I picked up that will donate a lot of parts to this 325is... a hail damaged, engine-less silver 4 door E36 M3. This one was also picked up locally and we will use this chassis' front and rear sub-frames, M3 brakes, M3 diff and halfshafts, and M3 bodywork for the ST2 build.

The '92 325is came in our shop today and was pressure washed, where many months of tree doodoo was removed. Body is very clean, just lost a lot of luster and some more clear coat thanks to mother nature. The crew in our shop also began building adapter beams for our roll around "body dolly" so that we can get this E36 chassis mounted to our custom built dooly, then remove the front and rear subframes and still be able to roll the car around. Once it is on the dolly we can begin by pressure washing and painting the underside (white epoxy paint), then the chassis reinforcement and cage work will start. To avoid any problems with ST rules it will only get the same reinforcement plates that come on the OEM '96-99 M3. We will TIG weld the Turner rear subframe and rear swaybar reinforcement kits as well as a front K-member "motor mount reinforcement kit". Then we will remove, cleanup and swap over the M3 K-members and rear axle parts to this ST2 chassis and the 325is subframe bits will go onto the badly dinged up M3 to make it into roller. Then the M3 roller will be sold off (100% rust-free Texas chassis with a clear Texas title, anyone?). Could be a good buy for someone with a Rust Belt M3 that was getting a bit crusty - after they switched over their drivetrain, diff, seats, hood and trunk, it would only need some roof work and it could be a rust-free running M3 again. Who knows.

Wait... What Class is That?

Some of you may not have heard of ST2 or even TT2. These are two different classes that share the same ruleset within NASA's racing hierarchy.
As you can see if you read the actual rulsets, TT2 and ST2 are essentially identical, with the difference being that ST2 is made for W2W racing and TT2 is a time trial class, without the same safety requirements. A lot of cars are built to run both, which you can do in the same weekend if you "Supersize" your entry. Gives you 2x the track time and twice as many chances at contingencies for not much more cost. Great deal for NASA racers.

The intent of this E36 LS1 build is to make a legal ST2 "Wheel 2 Wheel" race car that we can race briefly (likely in TT2, so we don't get a scratch on it), all with the intent to sell. Big "FOR SALE" decals will go on from day 1. It will be built around 18x11" Forgestar wheels front and rear and 315mm Hoosier tires, of course it will have a complete aero package, a full 1.75 x .095" DOM cage built to the NASA CCR, a pair of COBRA FIA legal seats, and a proper fire system. We will take it to a NASA event tor two, get it log booked, put in some lap times, then try to see if we can find a new owner for it.

This build will take the best parts and know-how we've used in our turn-key LS1 E36 installs, using the best LS1 swap parts on the market (duh - ours!), plus a lot of the knowledge we have gained from other race car E36 LS1 builds (like the original E36 LS1 "Alpha" car, among others) and racing in NASA since 2008. This build will allow us to turn this non-running 325is automatic E36 chassis, that was about to be discarded after it blew a head gasket, and transform it into a simple yet brutally fast race car that can be raced (hopefully) competitively in ST2 or TT2 class, against cars costing a lot more.

This class is based around an 8:1 weight to power ratio, which should be fairly easy to reach with this car. The goal is to get the chassis down to under 2600 pounds soaking wet and then use a mild (sub-400 whp) HKE-built aluminum 5.7L LS1 V8 and a T56 6-spd for the drivetrain. We want a reliable package with low cost consumables, big grip from the 11" wide wheels and tires, and some extra stick from added downforce. BMW handling + LS1 power = the best of both worlds.

Should be a fun little race car when we are done with it. We will post more here when we have progress to show.

More soon,

Last edited by Fair!; 11-23-2013 at 02:55 PM.
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