anybody put the tpi system on their lo3 but left the heads and cam?
i've got a setup that i want to swap onto my lo3 but i don't want to have to change the heads or cam at all yet. any idea what the result would be if i did this?

 

I did it on to my LO3. I did some fine tunning on the prom cause I have a SD set up and I am using a stock prom set up for a LB9. The LO3 has a small cam and heads that dont flow as good as the LB9 heads. But its pretty much "plug and play". It will run pretty good with out any prom tunning.

 

I'm using a stock LO3 engine under a TPI as well and it runs great. I've read in other posts while researching my swap that while the stock LO3 heads and cam don't flow well enough for big HP gains the torque will receive a big boost. I'm also using a speed density system with a stock '91 PROM along with an adapter from TPIParts.com to correct for 22# injectors and to disable AIR, speed and rev limiters and disable the A/C request as well.

 

TBI to TPI will NOT GIVE a big HP increase. Just won't happen. The TPI intake is often more restrictive to the engine than a TBI setup is. Torque around 3,400 rpm will get a good boost though.

 

Search for posts by me and my dad Dyno Don. We changed the L03 TBI to a TPI intake with a 7730 speed density computer, while keeping the same cam and heads. The power went from 158 rwhp to 176 rwhp, and the torque went from 220 to 290. The tranny was a T5, it had a 9-bolt 3.27 in the back, and a stock 2.75" cat-back from an IROC in place of the 2.25" stock TBI exhaust.
My dad said the difference in the car was incredible, and he highly recommends it.

 

alright so it seems that i won't have any problem putting it on i just need to get a new fuel pump and all the new gaskets. but one other concern that i had is the vats i don't think that i should have a problem because i'm using an ecm from an '89 which had vats and my car is an 89 and it has vats
so there should be no problem. right?

 

There should be no problem as long as the vats module is hooked up to the ecm to send the vats signal.

 

As long as your car has VATS and the donor had VATS you shouldn't have any trouble.

 

the tpi setup is from an 86 but the ecm is from an 89, so the car the ecm came from had cats but the car the tpi setup came from didn't have vats

 

As long as the ECM is from a VATS car and your '89 has VATS you're good. Just make sure that you use a harness from an '89 car so that the pinouts for the harness will match the rest of the car. Also with an '86 TPI the baseplate's center bolt holes won't match your heads. They're at a different angle. You can elongate the holes or use an '87-up base.

 

yeah i've got the base taken care of, but my harness is from an '86 without vats, i can't afford to buy another harness, what kinds of problems do you think i'll run into other than the car not starting?

 

anybody else have some input on this?