Ok guys, this may be here somewhere, but I will ask anyway...where is the prom located on my 89-305 TBI-Camaro.....By just freeing up the exhaust, and the Air filter, is there any sense in doing anything to mine...Thank you for the help....

 

The prom is in the ECM. The ECM is in the passenger side dash - you need to remove the "kick panel" on the passenger side and the ECM will be in the dash where the "glove box door" would be - if it had a glove box.

As for tuning your eprom for your "mods" - if you plan just buy an "off-the-shelf" eprom, you're basically wasting your money. However, if you plan to "learn to burn", yes it does help.

GM has "sloppy" programming to minimize "warranty claims". Also, every engine is a "little different", even if bone stock. One engine may be able to handle a little more spark than another - and that little extra spark can result in a "little extra power". Ditto on the fueling...getting your Air Fuel Ratio closer to 12.8-13.0 can result in more power if your engine is running overly rich (the usual problem with stock programming) or a little lean.

Lastly, if you plan to do "future mods", then it is better to start "learning to burn" on a basically stock engine. If you screw up, you can easily revert to the original programming and start all over again. However, if your engine is heavily modified, you will probably find it too intimidating to start to "learn to burn" as you probably won't have a clue where to start.

In other words, if you plan to climb Mt. Everest, you don't start by climbing Mt. Everest without practicing on a couple of "bunny hills" first.

 

Hey Grim,
Thank you for your reply.......Very informative...Have had 3 or 4 third gen cars, but never used any of the stock electronics..Just went old school ie..Carb, HEI, well you know...Now I want to keep all the vehicle intact other than the motor itself.....Thanks again...Tom

 

If you are comfortable tuning a carb/HEI setup, tuning within an eprom will seem like child's play. There are a LOT of tables & constants, but in all honesty, the vast majority never really need to be changed.

The beauty is, you don't even have to get your hands dirty.

 

Well Grim, thanks for the info...I talked to a guy who makes custom chips, and he said on the older ones (1989) like mine the chip does not really control as many parameters as on the newer vehicles...I think he said timing, and fuel mixture......Perhaps, I will worry about it later down the line, as I have only done the flowmaster, kand n, and the airbox off of a TPI car......Tom

 

Yes, newer systems certainly do control a lot more. And, not just the engine but also the automatic transmisson too.

I will agree that of all the ECMs & bins, the 1989 TBI doesn't have a ton of items to control. But, it most definitely have enough, including the most important things; the spark and fuel.

Of course, you could look at RBob's EBL system for TBI engines if you want more versatility. DynamicEFI

I have only limited knowledge of the RBob's EBL system, but there are a number of posts on the EBL system which you may find useful and you can always send a PM to RBob if you want more info on it.

But, I know a number of guys who "only" have a late 80s TBI F-body, and they are very happy tuning it and getting good results.

 

Well once again Grim, thanks for the info...I know next to nothing about these...(never had one) I am kinda old school, but I will look into it if you think it is a worthwhile endevor......Down the road is a motor swap for sure, but for the next year I will make do with the poor ol 305.......

 

If it makes you feel good, I'm old school too (and past the half century mark as well). As a word of encouragement, once "an old guy" get's past the initial apprehension of "computers", they usually take to the actual "tuning part" quite fast. They usually are astonished by how much more they have to control than they ever imagined....even with the stock TBI system.

It's just a different method of tuning an engine...but the concepts (the amount of spark advace, the spark curve and fuel curve) is still the same.

 

Yes, I guess you are right......I am little scared of the things I dont fully understand.....And im right there near the half century mark myself....I raced for years running a Dodge, and it was pretty much simple stuff...MSD..ETC, but no real computer controls..I will do more research on the subject...Once again, my thanks to you.....BTW, really love the thirdgen board.....Tom