Turbocharging L48s
Thread Starter
Racer
Joined: Dec 2005
Posts: 368
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From: . New Zealand
Turbocharging L48s
My 76 has a '92 L48 copy crate engine in it, has done only about 20K miles, I have been considering power adding options, and I have access to turbochargers for next to nothing. Has anyone else done a twin turbo deal under the rams horns, the intake can be fed to a pressurised carb box via an intercooler. Sound feasible?
Drifting
Joined: Apr 2002
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From: New Baden Illinois
Thread Starter
Racer
Joined: Dec 2005
Posts: 368
Likes: 4
From: . New Zealand
Its not exactly the same as a L48, whilst these Goodwrench crate engines were not world beaters, they do have some redeeming features such as 4 bolt mains and flat top pistons, I admit they are cast but should stand about 8lbs of boost, fine.
Heres a link for this type of crate engine dyno testing, it's an interesting series of 8 articles where they eventially got over 400hp out of it without changing the shortblock except cam.
http://www.chevyhiperformance.com/techarticles/46320_gm_350_crate_engine_build/
Heres a link for this type of crate engine dyno testing, it's an interesting series of 8 articles where they eventially got over 400hp out of it without changing the shortblock except cam.
http://www.chevyhiperformance.com/techarticles/46320_gm_350_crate_engine_build/
Drifting
Joined: Apr 2002
Posts: 1,716
Likes: 4
From: New Baden Illinois
Its not exactly the same as a L48, whilst these Goodwrench crate engines were not world beaters, they do have some redeeming features such as 4 bolt mains and flat top pistons, I admit they are cast but should stand about 8lbs of boost, fine.
Heres a link for this type of crate engine dyno testing, it's an interesting series of 8 articles where they eventially got over 400hp out of it without changing the shortblock except cam.
http://www.chevyhiperformance.com/techarticles/46320_gm_350_crate_engine_build/
Heres a link for this type of crate engine dyno testing, it's an interesting series of 8 articles where they eventially got over 400hp out of it without changing the shortblock except cam.
http://www.chevyhiperformance.com/techarticles/46320_gm_350_crate_engine_build/
I am not sure what dollar amount is "next to nothing", but if it costs anywhere near a typical turbo, you could probably do a fairly good head and cam upgrade for less money.
Team Owner
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From: Crossville TN
I've wondered the same thing... With the L-48 having an 8.5:1 CR, it would seem to be already set up for a low pressure turbo or supercharger. With a 2-bolt main and cast components, you wouldn't want to put too much stress on the system. But I would think you could get an extra 60-80 HP out of it pretty easily...and that would get the engine up to about 300 HP at the wheels. If the turbo (and related hardware) can be had readily and you can do the pipe welding...why not?
Speaking of that, could you scavenge a turbo off some other wrecked production vehicle to do that job? What unit will be a good match with the L-48 engine?
Speaking of that, could you scavenge a turbo off some other wrecked production vehicle to do that job? What unit will be a good match with the L-48 engine?
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I've wondered the same thing... With the L-48 having an 8.5:1 CR, it would seem to be already set up for a low pressure turbo or supercharger. With a 2-bolt main and cast components, you wouldn't want to put too much stress on the system. But I would think you could get an extra 60-80 HP out of it pretty easily...and that would get the engine up to about 300 HP at the wheels. If the turbo (and related hardware) can be had readily and you can do the pipe welding...why not?
Speaking of that, could you scavenge a turbo off some other wrecked production vehicle to do that job? What unit will be a good match with the L-48 engine?
Speaking of that, could you scavenge a turbo off some other wrecked production vehicle to do that job? What unit will be a good match with the L-48 engine?
....pretty dismal for so much work 
Melting Slicks
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You can run 7 to 9 psi without major mods, I put a turbo on a 1974 Ford with factory cast pistons (pre-hypereutectic) running 9 psi with no trouble. Now days factory pistons are cast using the hypereutectic process. I think the Corvairs ran around 7 psi, cast pistons from the factory.
Last edited by shafrs3; Apr 18, 2007 at 10:27 PM.
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From: All humans are vermin in the eyes of Guru VA
Cruise-In IV Veteran
Cruise-In V Veteran
On turbomustangs.com in the GM section they have an old truck motor with some GN turbos and a big hit of nitrous that seems to be working well.
