4.2 Turbo big power levels wanted where should I start?

[j88l98irocz]

Hey guys,

I'm looking for some information on how to build a 4.2 style I6 for big power, at least 1000 rwhp. is this a reasonible goal or should i quit now? What crank should be used?, Rods?, pistons? ect I'm making around 700 with my tt 383 at 18lbs of boost. I really like how the i6 scream in rpms, plus it would be different to see in a third gen camaro. Any help would be greatly appreciated thanks, John

[scotte]

you for sure want to start w/ a 06and up motor (or a 02-05 w/ a 06 head)

figure out if your going to use a gm computer or aftermarket ems (megasquirt etc) THEY BOTH HAVE PRO'S AND CON'S

if you use a gm computer i sugest getting a complete engine/wiring harness/computer from a 06+ (the 02-05 pcm is not desirable for boost)

supposedly an 08 pcm/tcm (they are seperate in 08) is better for boost than a 06-07, but a 08 engine has a different pattern trigger wheel welded on the crank (read 08 pcm will only run on 08 engine and 06-07 pcm wil only run a 02-07 engine)

you want a early style (02-05 iirc) fuel rail (return system instead of returnless)

i recommend reading what efi-diy has done

he will be on here soon whispering about how megasquirt is vastly superior


personaly i'm gonna be running a 03 stock engine w/ a p12 pcm (06-07) w/ a smaller turbo and 6-8psi of boost

imho if your going over 9psi you need to build the engine like efi-diy

but its not my definition of cheap

[hatchet669]

2 things...

once u get up in posts u can search some people have done this..

second is the fact everythign u need to push out the so called 1000rwhp u will need to get it all custom made... there is no aftermarket for this engine... there are peple that have put them in hot rods and running in the 8's... but its all fulley custom.. pretty much the only thing we have in common is the block and maybe the head... everything else custom measured, grounded, and made for it and its purpose...

not trying to burst ur bubble but this engine will be a costly one to make if u cant make that parts urself... u will also not to be able to use the stock electronics due to the purpose u want it for... if u go for it keep us up to date and maybe get an aftermarket for us made lol best of luck

[j88l98irocz]

thanks for the input guys. I will be using the big stuff 3 stand alone. I allready have a Aeromotive fuel system. I think I would go the sheet metal intake route with custom a fuel rail and an ls1 cable throttle body and a big turbo and intercooler. I assume since everything has to be custom made it will take some time and be expensive. The ? is how expensive.

p.s my car is gale banks twin turboed now making around 700 to the wheels Im using a t56 and a ford 9in rear heres a pic

[hatchet669]

pic =

but yea its gunna be a few bucks... i know a custom dual cam will be proably 1k if not more... crank shaft not sure on cost. most of internals will proably be able to get off shelf... hopefully... not sure bout that.. dont know what our piston size and arm size in... but something tells me it will be worth it

[j88l98irocz]

I can get custom made pistons from JE I need to find out about connecting rods, stud girdle for the main bearings, crankshaft, and how much power the block will hold... I want to do this right the first time.
I cant believe how hard it to find information on turboing the 4200 I6 if this was a 3 litre 2jz supra motor the sky is the limit

[j88l98irocz]

[QUOTE=j88l98irocz;623849]I can get custom made pistons from JE I need to find out about connecting rods, stud girdle for the main bearings, crankshaft, and how much power the block will hold... I want to do this right the first time.
I cant believe how hard it to find information on turboing the 4200 I6 for big power... if this was a 3 litre 2jz supra motor the sky is the limit, its insane some of the power numbers that they get out of stock supra motors with a big turbo

[whitedevil666]

[QUOTE=j88l98irocz;623852]

Originally Posted by j88l98irocz

I can get custom made pistons from JE I need to find out about connecting rods, stud girdle for the main bearings, crankshaft, and how much power the block will hold... I want to do this right the first time.
I cant believe how hard it to find information on turboing the 4200 I6 for big power... if this was a 3 litre 2jz supra motor the sky is the limit, its insane some of the power numbers that they get out of stock supra motors with a big turbo

You should start here:
http://forums.trailvoy.com/showthread.php?t=33447

Read the whole thing and for 1000+ hp do all the things DIY EFI has done to his.

[j88l98irocz]

Thanks man, There is still no info on how much power the stock Aluminum BLOCK will hold. That stud girdle is interesting looking.

[hatchet669]

never know its breaking strength unless u test it