soooo... early model fuel injection
Thread Starter
Intermediate
Joined: Jun 2010
Posts: 26
Likes: 0
From: MA
soooo... early model fuel injection
Sorry for the ignorance when it comes to tuning, but could someone please explain why my fuel injection can't be tuned to upgrades. I know the maf will make up for any difference in the air and such, but why cant i change out my injectors without having my chip sent out and is it big bucks to get it reprogrammed? How will this effect a 383 swap?
Le Mans Master
Joined: Aug 2000
Posts: 8,838
Likes: 31
From: Australia
Most '85 owners go to a aftermarket computer ( Megasquirt , etc ) or change to the 86 -89 ECM for better tuning and support
When you put in larger injectors and don't tell the computer ( reprogram ) then it will add fuel thinking small injectors are still in there; engine will be rich everywhere and the computer will be fighting itself trying to control fuel
@150 - $200 if you have a '86 or later computer
Burning Brakes
Joined: Apr 2004
Posts: 762
Likes: 2
From: Huntington ma
Actually... the ECM (actually the PROM chip) in the '85 is Simple and Easy to reprogram. It's the only GM ECM that used a "bare" PROM, meaning that the chip itself is easy to remove and place into a PROM reader/burner. No adapter cards or sockets required.
Otherwise the '86-89' ECM is essentially the same thing, with the complication of using the PROM chip on a small card, and the fact that the ALDL data output is at a faster baud rate. The other difference in the systems is the '85 specific MAF module is replaced by a pair of power relays and added circuitry in the ECM itself.
You do need to have the right tools and equipement, naturally. Some idea of what you are trying to change and the software to enable you to change it.
Start by reading thru the Many pages of the post in the sticky - you Will find what you need to know in there.
Otherwise the '86-89' ECM is essentially the same thing, with the complication of using the PROM chip on a small card, and the fact that the ALDL data output is at a faster baud rate. The other difference in the systems is the '85 specific MAF module is replaced by a pair of power relays and added circuitry in the ECM itself.
You do need to have the right tools and equipement, naturally. Some idea of what you are trying to change and the software to enable you to change it.
Start by reading thru the Many pages of the post in the sticky - you Will find what you need to know in there.
