3500 and 730 ecm in Fiero

[LZeppelin513]

I currently have a fiero with no engine in it and am considering the 3500 for it, but i have little experience mechanically. I am planning on getting the crank trigger from this store and using a 730 ecm with the 3500 harness. I also know that i would need some tunning equipment to get this firing properly but that is where my knowlege ends. I have read swaps on how to convert the fiero 2.8 or a 3.1 to the 730 ecm on the Pontiac fiero forum, would it be much different than that? could anyone point me to a thread for this or give me advice or any pin out pictures for this swap? Any and all help is appriciated!

Thanks, Blake

[Superdave]

i'm running a 3500 on the stock Jbody harness and '7730 ECM (custom chip) with the external trigger that Ben sells. Everything works/runs great.


the 3500 harness is completely different and won't work.. your best bet is a harness from a cavalier or beretta with the '7730 ECM and start there

[LZeppelin513]

Ok i am retarded , Joseph Upson already told me to use the fiero harness, thanks for the response tho, BTW your car is bad ass

[LZeppelin513]

Ok so with the 3500 and the 730 ecm and a getrag, what needs to be disabled in the computer? is it easily done with tunning hardware? Thanks

[Superdave]

Ok so with the 3500 and the 730 ecm and a getrag, what needs to be disabled in the computer? is it easily done with tunning hardware? Thanks

the only thing i have disabled is the EGR, the rest of it is all there... just adjusted ALOT.

With an ALDL cable, freescan and tunerpro you can do about anything you want to that computer...

and Thanks

[LZeppelin513]

Ok great. do you have to pass a sniffer in your area? I was thinking about not running the egr also. think this engine would be clean enough to pass a sniffer test without one? I dont have to have any visual testing like california, just the tail pipe test. and also what tunning equipment do u use? do u use a wideband? Thanks again!

[IsaacHayes]

I think with a good tune you could get away without the EGR.

[Superdave]

there is no testing in my area, i also don't have a cat.. lol


i doubt mine would pass any tests anyways

if you tune it right you could get away w/o having the EGR but it really dosen't hurt anything. I built mine for the track so i wasn't worried about the EGR or the other stuff. I'm using the stock 3500 4 wire o2 to tune with, it's good enough to get me close. right now it's still running rich which is fine w/me.

[Joseph Upson]

there is no testing in my area, i also don't have a cat.. lol


i doubt mine would pass any tests anyways

if you tune it right you could get away w/o having the EGR but it really dosen't hurt anything. I built mine for the track so i wasn't worried about the EGR or the other stuff. I'm using the stock 3500 4 wire o2 to tune with, it's good enough to get me close. right now it's still running rich which is fine w/me.

I recall reading that the 3500 4 wire O2 sensor is different in a manner that makes it incompatible with earlier computers despite being properly connected. I'm sure I read it because I have 3 or four in like new condition and I stopped wiring them into the harness because of what I read on either this forum or Z24 regarding the matter.

[Superdave]

I recall reading that the 3500 4 wire O2 sensor is different in a manner that makes it incompatible with earlier computers despite being properly connected. I'm sure I read it because I have 3 or four in like new condition and I stopped wiring them into the harness because of what I read on either this forum or Z24 regarding the matter.

I'll double check the part numbers but i'm pretty sure it's the same as the 3400...


*edit, youre right they are different part numbers.

I capped both the 3500 ones i have and put the 3400 one back on.. I won't know anything for a week or so (headers are out for coating)

[LZeppelin513]

Hmmm, could one of you guys explain to me what you are taking about with the o2 wires....is it something i would need? Im a bit lost, because i am new to tuning, thanks