Hey guys, one year of school left. ive been reading up in this section and know a decent bit about forced induction, applications etc... but i'm putting together plans for a turbo charged LT1. The motor will be a forged 355, gonna get one from a reputable builder...but that's not relaly the part I need opinions/advice on.

I bought Corky Bell's (sp?) book maximum boost, and will be reading through that a number of times. Probably looking at the PTK gen-2 kit for the system, or maybe fabbing up a twin kit of my own...but initially will most likely stay single prefabbed kit...

So the turbo kit and motor are the easiest parts (at least for me to understand personally). The big qustions I have are what type of engine managment are you guys running on the turbo cars? All the turbo cars I have dealt with (which now that i think about it are only supras) are all MAP based, should I be looking for a 93 computer and wiring harness? Or is there a whole completely different system (other than stock pcm eng. management) that I should be using? Also how about fuel? I saw the post on the dual in-tank pumps, that is the way I would go, does anyone have some in depth reviews/ write-ups of the different ways to accomplish this?

I realize I asked a lot of questions, but any help you guys can throw my way is greatly appreciated. I've got a lot of time to decide on parts etc later, just tryin to get a good idea of what all i will be getting myself into.

thanks

 

There's several options for computer control. The stock PCM comes to mind first. It's cheap and pretty reliable, but it can't see boost. Alot of guys will tune around this limitation, but it's not always dead on.

Another option is a stand alone controller such as FAST or DFI or even Motec (it's way more expensive though). These systems are speed density (except the Motec) and they can be tricky to set up correctly. WOT usually isn't a big problem to program, but getting them to work correctly under part throttle conditions can require alot of time on a dyno. Also, the newer versions of these systems can run low impedence injectors without a converter box.

There is also the new Big Stuff 3 system that a few guys are starting to use. One of the neat features of this system is called Staged Injection, similar to that used on the new Ford GT motor, it allows the use of 8 normal injectors to feed the motor under normal driving conditions, and an additional set of injectors to supply additional fuel as needed. Very cool.

For the fuel system, several people have run the stock lines to 700 hp or more with upgraded pumps and rails. Once you go beyond that, the fuel system can get really expensive to upgrade. Lines, pumps, injectors, regulators, controllers. It all adds up really fast.

 

very interesting (the staged fuel injection). Any idea how the staged injection works, i would assume those "staged" fuel infectors have a separate pump, lines and mgt system altogether? I would also assume this would require pretty big modifications to the intake manifold to house the extra injectors, but we all know what assuming does.

Well i was thinking about it anyway, but I suppose i might as well just pick up a book on engine management/fuel systems. Anyone have any sugestions as to some informative publications on the topic?

Thanks for the info 97WS6SCharged. For the intial project i don't see the system putting out more than 700 hp range...but then again i do know boost is addictive.

 

BS3

 

Well, if I were to attempt it (and who knows, I may), I'd run a single large set of rails (definately one off pieces) and have all the injectors tied into it. Not much sense in running two separate fuel systems. I'm sure you would need to alter the angles at which the injectors spray since it probably wouldn't be possible to mount 16 injectors straight up and down on an LT1/4 intake. It would probably be better to run a different intake manifold for best results. As for the extra injectors, they should only trigger when the computer sees certain preset values such as x amount of throttle or boost.