I'm in the process of swapping an LT1 into my 83 TA, and due to the bs at lt1wiring, and multiple other obstacles, I have been contemplating the alternatives. I absolutely do NOT want to carb the engine, so I have thought of the following and would like some feedback.

I was thinking of using the Holley 670cfm tbi unit which I can get from a buddy for a hundred bucks, and the wiring system from my 90 Bird with tbi, and using the GM LT1 carb intake with tbi adapter plate.

How do you think this setup would fair. I know the computer from my 90 305 tbi would be junk on the LT1 so I was wondering what the costs would be to get a computer from a 350 tbi engine and have it properly programmed to run the LT1 tbi system. Using tbi would also negate the need for a high pressure fuel pump which helps with cost of build.

And I'm just weighing my options and seeing what can be done here, and what could work, so if your just gonna post to be rude or belittling then grow up and leave the thread. I'd like to hear from those who know what their talking about.

 

Unless you're really into self-inflicted pain, do the LT1 system.

That's not rude or belittling, that's seeing things for what they are.

Hooking up a few wires from car to engine harness has got to be a lot easier (and what sooooo many have already done) than trying to marry two completely different induction and ignition systems together.

 

Can you ditch the opti-spark from the LT1 and run a distributor if you are using an LT1 carb intake?

If you can do that, I don't think it would be too bad. Then you can run the TBI and tune your computer for a 350.

I don't know that I'd run the Holley TBI, I like the bigger modified units off of eBay.

 

I know its a bit of an odd setup, but I honestly dont see that it would be hard at all to pull off. As far as the LT1 system, I'd love to use it but I got a 96 LT1 and the harness is strange as hell, and OBDII pcm, I ended up selling and then got an OBDI pcm, but the harness has me completely lost, not to mention parts are missing on the intake and injector plugs are missing, and a multitude of other issues.

Do you really think the setup I mentioned would be so troublesome? I've read enough on the site from you to know that your not going to tell me a bunch of bs, you've always seemed straight with people. Could you clue me in on any major problems I'd run into with the formentioned setup? To be honest, I'm starting to think it would be much less headache than trying to rig this LT1 setup in.

 

Yes I can run a distributor with the LT1 carb intake, and that would be the way I'd go. I'd just leave the opti in place but not used.

The Holley tbi has 2" throttle plates and is 670cfm. Do you really think an LT1 needs more flow than that? As far as the ebay tbi's, I'm pretty leary of ebay stuff, lots of garbage sold on there.

The way I'm seeing it is that by going tbi, I could get the added torque that the carb intake offers over the lt1 intake, but still keep it an EFI setup, and also maintain decent high end grunt.

I'm not doing much to the engine, just a bigger cam, long tubes and CAI. I thought 670cfm woulda been plenty. Dont wanna go to big.

 

I am talking about this piece from extreme fi:

http://cgi.ebay.com/ebaymotors/454-3...QQcmdZViewItem

99.8% feedback rating and 3507 transactions, that's pretty good at eBay. I'm not pushing anybody's products but I will be using this on my next TBI engine. it uses the normal 305/350 air bleed passages (the 454 unit is a little different) and it also has 50mm butterflies (a tad bigger than 2") and is supposed to give 750 cfm flow.

You could run the LT4 hot cam and put a little tune on your TBI computer and really have a barnstormer...

 

Looks tempting, but take a look at the auction, that TB unit is basically bare, no injector pods, they basically sell a stripped TB. Not to mention that once you bought their injector assembly for another $130 that comes with crappy injectors, the cost is Way more than it would be with the Holley unit. The Holley unit comes complete for barely more than that unit and has an adjustable FPR.

 

I'll be using it as an upgrade for my existing stuff. I can re-use all of my 350 TBI parts on this throttle body and then I'll turn up my fuel pressure for tuning. Maybe I'll use 454 injectors eventually...

If I use 454 injectors at 86 bucks each, I can brake even with the holley price and do much more with my TBI unit. Of course this is because I already have a good 350 unit to take the hardware pieces that I need off of. I can get another one at the wrecking yard if I need to, though...