My Twin-Turbo SBC 240Z Build by PaulR

By diyauto
( 3 )

5 minute(s) of a 13 minute read


My Twin-Turbo SBC 240Z Build

Compliments of PaulR @


Sometime back in 2004, after seeing Siliconeboy’s turbo project in process http://forums.hybrid...ead.php?t=89810 , I got inspired to do a Twin Turbo set-up in my 350 Chevy powered 240Z. It didn’t take to long to find the Corvette manifolds and a pair of T3/T4 (.60/.63) from Ford Turbocoupes (inspired by Mike Sitar’s “toohighpsi” Capri http://www.toohighps...TT/BudgetTT.htm 

These items sat in my garage collecting dust for the next 4 years 

So, last spring I decided it was finally time to get this project in gear. I started by installing an intercooler and relocating the surge tank I was using to supply the Holley Commander EFI system. 

I built an air hat using the tank from a “pancake” style air compressor that I had burned up the motor on. 

Since I wanted to keep the car on the road for the summer, I ran the air hat and intercooler on the NA engine… that got some interesting comments from people peeking under the hood. I jokingly told them that it was a high-tech cold air intake system.

Around September of this year I parked the car in my shop and got busy building. Lots of stuff had to be relocated to make room and to avoid heat issues. Fuel lines, brake lines, and wiring was re-routed. I moved the battery to the back of the car and used the spaced to mount a bunch of other stuff where it would be out of the way (fuel filter, relays, 2-BAR MAP sensor, coolant overflow tank, Wide-Band O2 sensor module)

I fabbed up the manifolds (thanks again to Siliconeboy for the idea)

Did some fit checks.

Built the down-pipes, cold side, etc

It’s now all together, (as of today) but I haven’t fired it up yet. Hopefully this weekend.

And, it all fits under the hood J

Thanks for the compliments. I plan to keep it fairly tame (at least at first). The engine really isn't built for boost. It's a 2-bolt block w/ cast crank and hyper-eutectic (sp?) pistons (9.5 CR). I would like to hit 400 rwhp, which I figure I can get with around 6 psi boost. Next winter I plan to build a motor that can take 10 or 12 PSI (forged internals, 4-bolt, etc)

BTW, this is stictly a street machine.


Pretty slick, I bet that thing moves!

Posted by stevegolf on 12/24/20 @ 2:19:40 AM