camarocruzer

How difficult is it to swap out from TBI to TPI? I've got a 91' camaro convertible. Is it worth doing? If so, what combo would be advisable to use? A stock 305 Tpi setup maybe port and polish the manifold and heads, or some aftermarket heads and manifold? Is it a headache computer-wise? Thanks

thomas1976

If you are after the 5L TPI's cars power, you need to find a 91-92 donor car and swap transplant harness, computer, TPI, cylinderheads, cam, fuel pump, air intake, full exhast.

In this situation I would look for a 91-92 5.7L donor car and transplant the complete Long block at the same time.

camarocruzer

I actually have an LT1 sitting on a stand in my garage, but i just had the 305 that's in the car rebuilt. Motor has less than 500 miles on it and I really didn't want to swap the stock block out. Would the heads and other parts off of a 350 fit on my stock 305? If so, what year donor car would i need to look for?

jamieschott

iTrader: (2)

As far as the harness goes, you can use the TBI harness and re pin it to TPI by following the link below. I performed this last year and have had no problems with tuning and driveablity. You will just need to get a TPI computer and make sure the Memcal you get is a stock V8. All that is needed is in the thread below.

I did purchase a tool to help me with the repinning process. Although several have used a paperclip to perform this. It only took me a couple hours to do this. Just recheck your work a couple times is all I suggest.

https://www.thirdgen.org/forums/tpi/...d-density.html

As swapping the intake, I beleive there is a tech article on this...
https://www.thirdgen.org/tbitotpi

I didnt do this . I installed the FIRST injection intake on a 383 crate engine when I did this last year. And havnt looked back

Vitamin Bee

Hello camaro people! I need some information on tbi to tpi swap.
I have a 305 tbi 89 RS camaro. The tpi system I'm looking at is off a corvette 350. Will it bolt on my 305? Will my factory harness plug n play with the TPI ECU? I just want to swap tbi to tpi with using my factory ecu and harnesses

Tuned Performance

iTrader: (92)

You will need to repin your 1228746 to tpi maf 1227165 86-89 ecm or 90-91 speed density 1227727.
The intake base inner holes need to be elongated to get your heads 72 degree from 90.
You will need the correct 305 Ecm calibrator.

Tuned Performance

iTrader: (92)

You will be better off going to the 1227730 speed density f-body ecm than doing tpi maf re wire.

https://www.thirdgen.org/forums/tpi/...d-density.html

Vitamin Bee

Is it worth the Swap tbi to tpi?

Drew

iTrader: (58)

In a nutshell, no. The intake manifold isn't the weak link in the TBI 305, it's everything else. TBI cars came with restrictive exhaust manifolds, restrictive Y-pipe, and the same catback as the 6cyls. Not to mention the dished pistons, swirl port heads, tiny cam, shitty gearing...

Swapping just the intake will probably gain a bit of torque, but it won't be as strong as a stock 305 TPI car.

DynoDave43

iTrader: (11)

But other than that, it's a great little engine!