jerome1979

I'm a neewbie in fuel injection, but i want to know if a Lt1 system can be put onto a ZZ4 engine?
what about optispark vs HEI?
......

Durango_Boy

I'm doing a similar swap, and finding that there are a lot of things that have to be done to install an LT1 manifold on a Gen1 block, like the ZZ4.

An easier and cheaper fuel injection swap would be either TPI or TBI. They can be found everywhere, and are set up for cars with HEI already.

TBI has more potential for power, and is readily available on everything from cars, to vans, to trucks.

To learn more about LT1 swaps, check out http://lt1intake.com/services.htm

Good luck.

jerome1979

[QUOTE=Durango_boy].......................
TBI has more potential for power, and is readily available on everything from cars, to vans, to trucks.
...................[\QUOTE]

Why TBI is better than TPI? i alway belive that was TPI better than TBI

good luck too for your swap

Durango_Boy

It has more potential, because a TPI manifold will get winded at high RPMs with a 350. It was originally designed for the 305, and later adapted to the 350.

If you go any bigger than 350 you run into problems with running out or air and fuel for large heavy breathing engines.

TBI is basically an electronically controlled 750 cfm carb. They can be modded to get to over 850 cfm, so adding them to a larger engine is a good option.

Plus, I hear it's easier to reprogram a TBI system for modifications.

Durango_Boy

I just wish those after market alternatives were not so expensive. That's why in the end, wanting EFI, I chose a factory LT1 style setup.

I'm Batman

Not really any difference in reprogramming, at least between the TBI and TPI (and the TPI computer can drive a modified LT1 without the OptiCrap distributor). The TPI intake does get winded early, but the LT1 (and the aftermarket LT1 clones for TPI systems) seem to avoid that problem.

jerome1979

If i take an used TBI system, can i add a 4 injector TB in place of 2injector TB and make it run ?!
i need 4 injector because i have a ZZ4 385fast burn with hot cam kit so it develop 430hp@5800 and GM require a 750cfm carb so a 2 bore seems to be "short" in CFM !?

Durango_Boy

Do some research, but I'm pretty sure you can get 850 CFM from a modified TBI throttle body.

Crazy81

Thats why I bought a LS1. After researching the aftermarket for EFI and TBI conversions, I found that I could buy a complete LS1 for about the same amount I would spend on just the aftermarket setup.

Durango_Boy

Yep...but you can do a TBI conversion from salvage yard parts, and a few hundred for a custom chip.

Much cheaper than a complete LS or even an LT, if done the bone yard way.