rx8ss

I have a 87 Iroc-z with a 5.0/ now 5.7 and a T5. I wanting to know if it would be possible to use the stock harness on a LT1. I would modify the intake to accept the distributor and delete the optispark. I know that the 92/93 LT1's used speed density batch fire. From what I can tell the early lt1's use pretty much the same sensors and locations. Tuning is my main hold up. I really do not want to rewire under the hood if possible.

Thanks for any comments.

FSTFBDY

iTrader: (33)

Yes if you remove the opti and drill for a distributor you can.

I did the same thing with my 383 lt1.


Get yourself a lt1 throttle cable. If ya have any other questions post em up or just ask.
Do you already have a LT1? What year? etc...

rx8ss

Yes, 383 splayed caps, squared decked, forged srp pistons coated top and all, I beam rods, forged crank, ported polished enlarged valves, 292 sfi cam, and more. Was building for another car but life changes caused other things to happen, but kept engine.

Set it up for anything I wanted to throw at it. I am liking to turbo idea, but with a tpi harness maybe not.

I do have a Autorotor supercharger off of a vortec engine.
Thanks

jaysfs

iTrader: (1)

this may sound dumb,but the motor is setup yoo where you can put a distributor in a lt1? i know the intake needs drilled. I am debating on a lt1 or ls1 swap and i like the prices alot better for the lt1 swap better.

FSTFBDY

iTrader: (33)

Why not turbo it with the TPI harness. You can run a STOCK 7730 ecm with the $59 code.
http://www.code59.org/index.php?opti...d=6682&catid=9

alot of people running Turbo efi setups here. Go check out the POWER ADDER FORUM.

Just drill the intake for a distributor , get it tuned n/a running on code 59 and add boost.
thats what Im in the middle of now.

383 LT1
callies crank, callies rods, je pistons, etc.. Novi 2000 sc pullied for 12 psi right now.

c10crewchief

So what Part Number of the ECM I would be looking for to perform a 383 LT1 swap as shown above? My dad has been told to look for a 89-92 TPI ECM preferable from a Firebird. Is this true? I have found some on eBay but want to make sure it is the correct P/N. Thanks

vetteoz

iTrader: (13)

So long as the engine has fuel and spark it will be happy It doesn't know what is controlling it.
You could even run the TPI MAF setup for easier tuning

vetteoz

iTrader: (13)

Depends whether you want to run the MAF system or the MAP (speed density )
Two different computers and wiring.
MAF , easier to tune has 1227165 ECM (86 - 89 ) but requires the MAF sensor on intake before TB

MAP uses 1227730 ECM (90 - 92 F-Body ) which allows you to run a air filter direct on the TB

1227727 is the Vette ( 90 - 91 MAP ) weatherproof underhood mounted ECM; uses different harness and ECM plugs

You will also find the same ECM's with different part #'s given by the factory when they went across the parts counter as reman units.
Need to cross reference to confirm

CreepingDeath94

iTrader: (4)

I don't know if this helps, but my '93 Trans-Am still uses a PROM style computer...they didn;t go to flash style ECMs until '94+. The computer just sits in the engine bay on the pass. side on the firewall area behind the wheel well. This may be useful since your TPI harness and ECM will be PROM based and located inside the pass. compartment. Just throwing that out there in case it helps with some of this...locations and such.

c10crewchief

Good, then I found the correct ECM. But if it says the memcal has been removed, then does that mean it doesn't come with a chip? Thanks for the info!

FSTFBDY

iTrader: (33)

correct. your going to need a chip/memcal if a Pre 93 ecm/pcm

raffi4

iTrader: (2)

So can i use my stock 87 305 tpi wiring harness and computer with any lt1 or specific year? Just with the distributer modification.

FSTFBDY

iTrader: (33)

Yes you can.
u need to use the lt1 accessories.
You need to mod the timing cover to get rid of the opti.
You need to drill your intake for a distributor.

raffi4

iTrader: (2)

Any lt1 or just 92-93? Details on modding the cover? also what did you do for the PS high pressure line?

FSTFBDY

iTrader: (33)

ANY engine will run of your harness.

I used AN fittingand braded lines for my PS pump.