LS3 Corvair

[tonym]

I thought I would post a little information on my project car-I put a little intro in the newbie section but wanted to show a few more details.

The engine is a 2011 6.2 liter LS3 with a GM LS HOT cam I installed. This is basically the same engine as installed in the 2010+ SS Camaro with a little more top end power with the cam change. Lets just say it has adequate power for a Corvair! I assembled this motor from a new long block that my local dealer had and couldn't use and an intake manifold a friend had taken off his Camaro for a supercharger upgrade, so I got into it at a good price. It is rated at 480 horsepower by GM.

I used the GM Performance Parts LS3 crate motor ECM/wire harness which means it was plug and play- no tuning!This setup has an electronic throttle pedal which I mounted on the floorboard and had enough lead length in the harness to mount the pedal without cutting the harness.

The transaxle is a stock 1994 Porsche 911 G50 5 speed run inverted with a Kennedy Products adapter. Kennedy makes nice stuff- it fit perfectly. The flywheel came from a GTM kit person who was upgrading and bolts to the LS motor but uses a Porsche heavy duty clutch. The nice thing about this transaxle setup besides the power handling is the engine is set back in the car about 4-5 inches more than the Crown conversion which gives you room for your legs and the stock front seats! It has a cable shifter that was sourced from a Porsche motorsports supplier- it works well with positive shifts and I can even get it in reverse!

The axles are custom CVs both ends with Porsche inners and Corvette outer CVs. A off-road shop in Rockford, Illinois did them for me and they are the only real custom part that is not "off the shelf" for this entire conversion (at least the hardest one to make). The rear suspension is "stock" C5 Corvette with coilovers (narrowed by sectioning 6 inches out of the cross member). The tightest fit was the rear C5 cross member to the Porsche starter- I had to rotate the starter 20 degrees to get the solenoid to clear the cross member-requiring a couple of "spacers" to mount the starter on the transaxle.

I welded in a separate subframe for the engine, rear A arms and transaxle mounts. The only issue I have run into so far is having enough adjustment for rear camber with the stock Corvette cam bolts- one of the hazards of doing things from scratch, the upper rear A arm mounts may need to be moved to get it right.

Plenty of room for the stock Corvette Z06 17/18 inch rubber-I just cut out the corvair shock mounts in the rear for clearance.

Front is Corvette C5 with a Mustang 2 steering rack -the rack is stock but the front corvette suspension cross member is narrowed about 5 inches to account for the narrower Corvair track width versus Corvette. I added mount points to the corvair front frame rails to bolt the corvette front end in similar to the original corvair front suspension.

The radiator is a custom 1969 Camaro aluminum unit with two high flow spal fans-it cools well with 1.5 inch cooling (water) tubes to the motor. These are silicone hoses from Speedway Motors for bends/hookup with aluminized steel exhaust tubing for the long runs under the floorboards . The hot air is exhausted through the louvers on the hood, but I may go with a GT40 style extractor vent on another hood I have. You may notice the front end lower valance is not cut at this point-cool air enters from under the front like a newer Corvette- I am adding an air dam to the car but I don't have plans to cut vents in the front valance unless cooling becomes an issue. The overall cooling design in front is very similar to a C5 corvette.

2 1/2 years to get to this point-driving but will need tweaks to be street ready-it needs a better clutch than I have now to handle the torque-I think the trans is up to the task if I don't beat on it. The Porsche clutch is the weak point right now. There are a few high torque clutches but I am going to have to open the wallet.

I am planning paint and body work this spring, thinking about a black paint job but the Maroon color is nice also. The car I used as a donor is rust free so I don't have to spend any time chasing rust-unusual for a Midwest Corvair for sure! The floor pans in this car are the nicest I have ever seen.

I am always looking for suggestions- any ideas are welcome, thanks for looking.

[Jerry Whitt]

Looks great! Suspect you used to be wealthy.

[tonym]

It wasn't as bad as you might think but the transaxle is the hardest thing to find at a decent price. I found this one for $2,500 and consider myself lucky. Especially now that I know it that it is in good shape!

It helps having no other dependents but a Wife and a Terrier!

[notched]

Very nice work!

[4carbcorvair]

Awesome!!!!!

[hrm2k]

I'll be watching this one. I wanted to do a 5 speed behind my SBC but the TH425 was there and at almost no cost, perfect for the job. Cage looks good.

[Phil Dally]

DUDE...bitchen car!!!!!!! Do you have the KEP 650 foot pound G50 clutch in it now?

[Scott V]

bitch'n ride! wow. great work your doing.

The car I used as a donor is rust free so I don't have to spend any time chasing rust-unusual for a Midwest Corvair for sure! The floor pans in this car are the nicest I have ever seen.

thats funny - seeing you cut 1/2 of them out.

-Scott V.

[Scott H]

Really nice build. Keep us posted on your progress.

[Tom Z]

Front is Corvette C5 with a Mustang 2 steering rack -the rack is stock but the front corvette suspension cross member is narrowed about 5 inches to account for the narrower Corvair track width versus Corvette. I added mount points to the corvair front frame rails to bolt the corvette front end in similar to the original corvair front suspension.
---very interested in this,the Mustang-II rack hasn't been too successful tho,which is why I stopped working on my 'mid-4.3'..not sure if all the work to make it "fit" would be an improvement..

[tonym]

The Mustang II rack needs to mounted a few inches higher than the lower front A arms to avoid bump steer- the distance between the inner pivots on the rack needs to be compatible with the width of the A arm pivots so there is not a conflict when the suspension moves- I don't see why you couldn't use it on a stock Corvair as long as it is mounted with this in mind.

I had to "c"cut the frame rails on the Corvair unibody and reinforce with steel to get the rack high enough in the car. It is a fair amount of work.

[tonym]

It has the Porsche turbo clutch in it now which will be replaced with the Kennedy clutch- the turbo clutch is not quite up to the task which is no big surprise but I had to try it. I will never understand why Porsche thought a 9 inch diameter clutch disk was a good idea, of course it works fine for a 3.4 L six cylinder.

[MikeBuongiorno]

Birds of a feather. Would be intersted in connecting with you Tony!

https://www.youtube.com/watch?v=8OOIyR_ ... 5giP0ZStrA" onclick="window.open(this.href);return false;

First start last night.

[DAN POLITTE]

Din you consider any other transacted for this build? Is there another option for a high horse and torque application?

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[DAN POLITTE]

Transaxle. Stupid autocorrect

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[james clark jr]

Hi my name James Clark I seen your corvair LS3 vary nice car I wanted to no do you have dimension on frame that holds engine and transaxle in place . And how the frame that holds engine and transaxle is bolted to body of car. think you .