Single turbo'd LS2 swapped into a Z3

[DrewP]

I'll throw up some photos as we go.


Myself and a co-worker (who is a Nissan guy - he's just wrapping up an SR20 swapped '94 4x4 hardbody pickup that should be good for about 500hp) are doing this swap for our boss in our (non-existent) spare time.

He started out with a green Z3 with a popped motor and was paying a local guy to do the work, but all he ended up doing was butchering up the body and losing half the car.

So, we picked up this clean white over black '99 Z3 to start fresh.

The LS2 is from an '05 GTO, I believe the turbo is a ball bearing GT45 with a 1.02A/R turbine. Should be pretty scary.



So far the engine is in and mounted, turbo is just about mounted, driveshaft was made by a local shop and is ready to go. It's got Hooker low-profile cast manifolds pointed forward and down into 2.5" delivery pipes, huge external wastegate, and a single 4" exhaust all the way out the back. The alternator had to be moved from the lower left to the upper right, but otherwise this will be a very tidy install, considering the turbo is the size of a large spaghetti squash. :redspot

The turbo is mounted down low in the middle of where the left side crush tube used to run forward to the radiator core support. Custom radiator and intercooler will go in front of the core support, as the space that the stock radiator used to occupy is now full of turbo plumbing and exhaust.

We chopped out the rail and plated the open ends, then waterjet cut the half-moon mounting flanges, plated those over with rolled flat stock, and then there's an aluminum horseshoe bracket mounted on standoffs that bolts right to the back of the compressor housing mounting plate.

[SwedeSport]

That's pretty friggen wicked!

That powerplant in a 9-5, attached to a T56, using the rear drive underpinnings from an Opel, would be even better.

That turbo looks like it could devour an arm if you got too close to the intake while it's running.

[Jordan]

Needs more supercharger

[Adrian Thompson]

That's a big turbo. What's the lag going to be like? Get in the car, floor it, leave brick on gas pedal, get out have a cup of tea then get back just in time for it to take off for warp speed? That's what old school 930's felt like. 2nd gear 40mph floor it. 40.5mph.....41mph......42mph.....50, 60, 70...... aaaggghhhh!!!

[DrewP]

It actually should be pretty good, it's actually a little undersized. We have like a 64mm external wastegate for it and will only be running 8psi... maybe 10psi to start. It's still stock compression ratio and the stock bottom end and cam, static compression ratio is like 10.25:1 or 10.5:1.

I remember vividly the ride I got in a '78 930 Turbo, it was absolutely terrifying. I had no idea there were cars that fast in the '70's. They're still very fast.

[SwedeSport]

I was at the track day at Putnam Park in 2002. It was attached to the SOC that year.

The PCA guys were our instructors for the day. I got a ride in my instructors car, and 89 911 twin turbo. It seemed to spool up pretty good. All the fun ended when he spun it into the grass at 140 and he broke the fuel line on the rumble strip. Limped to the pits...

That GM 8 should have a fair amount of power on its own without the turbo, so a little boost should go a long way on it.

[DrewP]

All the bolt-on Corvette and GTO turbo kits add about 125-150hp on about 10psi of boost. So ~550hp in a Z3 should be pretty amazing.

[mrazekan]

All the bolt-on Corvette and GTO turbo kits add about 125-150hp on about 10psi of boost. So ~550hp in a Z3 should be pretty rediculous .

Fixed.

Looking good Drew. Crazy project. I hope there is a budget for tires.

[DrewP]

I hope there's a budget for body work.... it won't take long for this thing to get stuffed into somewhere that is not a roadway....

[mrazekan]

I hope there's a budget for body work.... it won't take long for this thing to get stuffed into somewhere that is not a roadway....

How much does aerodynamics really matter when you are pushing 500+ Hp?

Wheelbase too short for top speed runs anyway. I'm impressed Drew. I didn't think the engine bay would fit a big v8.

Cheers!

[DrewP]

LS1/LS2 swaps into E36 3-series / Z3 cars are actually reasonably common. There are a few companies who make all the bits to drop these engines right in. Mounts, headers fitted to the BMW chassis, driveshaft, etc. Haven't found anyone else dumb enough to turbo it in a BMW platform though, but our company does pride itself at tackling challenges that other people just scoff at.

I'm wrapping up the exhaust tomorrow if I can put in the hours, more photos coming.

[Geoff]

So Drew, you had to cut the frame rail and make an arch to fit around the turbo. But then you bolted the turbo to the arch. I'd think with the engine vibrating, twisting on it's mounts, etc. you'd end up cracking the manifold or the mount that the turbo is bolted to. Am I missing something?

[DrewP]

There will be a flex joint in each downpipe right off the manifolds before they merge into the turbuin inlet flange. Then the turbo and downpipe out of the turbine will be hard mounted to the body.

I'm actually at work putting this together now. More pics in a day or two.

[Adrian Thompson]

The PCA guys were our instructors for the day. I got a ride in my instructors car, and 89 911 twin turbo. It seemed to spool up pretty good.

If it was an 89 Twin turbo it was a custom install, hence the rapid spool. The first twin turbo factory ROAD car was the 993 TT.

The 930's were single turbo with K jetronic injection. The lag was monumental, but man was it fun

[DrewP]

Some progress yesterday. Should have the exhaust all cut to size and tacked today.






Flex joint off left manifold:






Up-pipe and flex joint off right manifold. It wraps around the downpipe that comes from the turbine outlet.






Turbine inlet has plumbing coming from two different directions and not much space, so I made this little collector for where the two up-pipes merge:













I got a pretty good fit around the flange inlets. I smooshed the three sides sort of flat in a vise, then tacked the middle edge to the flange, then clamped the centers together with a vise and tacked those to the flange to get it to hold a roughly rectangular shape:







I also threw together a little 3-rd hand tool to use as a grounding contact, and plugged the openings with aluminum foil to backpurge the seam welds.













All buttoned up: