LT4 w/carb intake w/TBI & adapter or Port Injection? Has anyone attempted something like LT4 w/carb intake w/TBI & adapter? Any insight in to how well it would run? on a similar note, say the LT4 carb intake was tapped for fuel injections and had a TB on it, anyone know if a TPI computer is flexiable enough to be tuned to run that sort combo? Thanks

Are you talking about the lt4 hot cam, if so is pretty much my cam.

What other mods do you plan and do you have specs on the cam?
Port injection will yield more efficient results, but the cost to gain ratio may not be there.
As far as the computer goes, you may be able to get better answers from the diy prom or tpi boards.

i don't know anyone who has attempted to use a lt1 based engine with a carb adaptor and TBI, it would work given enough tuning, but it would be HARD to tune, also, if you are talking lt4 HP,and revs, even a 670cfm TB, may not be enough, you might have to aftermarket, and get a 800 or 900cfm 4bbl TBI system.

TPI computer should work, i am not versed enough in which would be better, but i assume that you would want to use the 90-92 SD computer, not a MAF system.

the hardest part of doing this is tuning it, there is going to be a TON of work to get it to run right, especialy the lt4 since it has a raised runner design, the VE stuff is going to have significant changes. if you are going to the trouble of installing a full lt4, why not just use the lt4 computer, and intake?

I've not picked a cam or worked on any spec as of yet. I saw an LT4 crate engine set up with carb and got to thinking, hey wouldn't that work with a TBI and the right tuning too?

Then it sort of occured to me, that port injection with a TPI computer might be possible while using a big TBI as just a TB.

Problem is I don't know nothing about TPI or TBI programing.

I'm sure it would be easier to use an LT1 set up and PCM.

Still the idea of getting an LT1/LT4 w/carbed intake and slapping TBI on it seems pretty novel.

Brainstorming....thanks for the comments.

There is another angle on this I can't really go into right now it's a long story.

If using the TB, you may consider using a cam with a Lobe Seperation Angle of at least 112*.

Also I would suggest reading up on the work and equipment required to log data and tune your cars computer chip.

Its all on this site and takes work, but is by no means impossible. I knew nothing about car computers when I started but after reading up and asking questions where needed, I'm only 1/2 the numbskull I was when I started!

It was at least enough to get me through a 305 to Vortec 350 swap with good fuel economy, good performance and no SES lights.

S-D