Twin turbo 3.4

[cypherbane139]

hey guys, im starting to gather info and everything for a 3.4 swap. ive decided to go the twin turbo route, because for 1:this build is going to be on the cheap(ish), and i have found 3.4 pushrod engines and t25's all day long, for practically nothing. (plus i dont have to buy all sorts of things to hook em up to my transmission which is 5 spd.) 2: I like the idea of having less lag, and since this isnt DOHC i dont have time to spool for some larger turbo setups.and 3:i would like to do something i havent seen done yet.

from what ive learned, some t25's from an eclipse would be efficient for the rpm range id be working with. the backpressure should stay lower than the intake pressure along my usable RPM, so i should be good with something like the ARI stage 2~ or running 1.6:1 rollers. the routing is what is getting me, im not sure if i should keep the exhaust sides after the downpipe seperate, or would it be more practical to have them pipe together. i would like to have dual exhaust, but i dont know how i would be able to route each to be about the same length, or even if it would matter.

I do plan on getting different pistons, dropping the compression to 8.5-9 to 1, and running around 8-10 lbs. if i can realistically pipe an intercooler, or get some methenol injection id shoot for more, but i dont wanna push anything, as this is still going to be a daily ^_^;;

my goal is around 250 hp, and a nice torque curve, what do you guys think?
am i totally retarded? lol

 

[Oreif]

Only 250 hp? You can get 230hp normally aspirated and around 280hp with a single turbo. The 3.4L already is running 9:1 compression. There was a guy who ran Falconer racing heads on a stock 3.4L with a single turbo at 16psi in a Firebird and hit 332rwhp on a dyno.

Here is how one guy did his twin turbo Fiero:
http://www.cardomain.com/ride/2564404/3

 

[cypherbane139]

wow, thats definatly an interesting setup, but man... thats alot of piping before the turbos lol.. i like the HVAC themed intercooler piping lol. Im hoping to be able to make mine a little more stealth.. damn i cant wait to start the build^^

so i should be able to hit 250-280~ no prob? have you heard any problems with the aftermarket cams not agreeing with some turbo setups on these engines? and will not having each exhaust side the same length going to affect performance (Ie: different backpressure) i would like to have equal length exhaust piping, but i dont want to compromise any performance.

i was also thinking about how i could route in two intercoolers, but after enough thought im thinking about having both pipe together and into a single intercooler. it would mean less sensors, less injectors, etc etc..

do you think hypereutectic pistons would work on a turbocharged engine if i set it up for around 10~ psi? or should i just fork out the bucks for some good forged racing pistons. again, this is still going to be my daily, i'm looking for some good punch, and a nice looking torque/HP curve ^^ once its set, im not going to mess with it much >_>;;