Would there be any advantage to swapping my California ECM PROM for a Federal ECM PROM?
The reason I ask is that my new to me 88 GT automatic just seems a bit sluggish compared to what I have had in the past as far as performance. My 2nd Formula was a California car, automatic, but just seemed to have more life to it. Yeah, I know the automatic will be a dog no matter what, but I am limited to that due to left leg issues.... stupid (but my best friend no matter what) dog and I had a race 3 years ago..... he won, I lost. heheheh....
My '88 GT began life in California, so as of right now I am assuming it still has the original ECM PROM in it. The federal PROM ECM number is AKYM3437. The California PROM ECM number is AKYR3452.
If there is a difference in performance, I would sure love to do the swap!
I am really curious as to the differences either way if anybody has that information.
If there is a difference, and someone has one, I would be very interested and will post a wanted in the mall.
Thanks phonedawgz, I will send a pm with payment and shipping to you later this morning. Looks like there is a bit of difference worth doing the swap for.
Sorry about that - I didn't connect your payment together with this post and was going to send an email and ask. I was busy getting things ready to fly out to Virginia Friday to pick up a GT and drive it back. Things went well and the GT is sitting in my driveway and now I am getting to these backed up things. It will be in Monday's mail.
quote
Originally posted by railshot:
phonedawgz, you ok?
Sent a couple of pm's to you and no replies.
Not worried about the $40 or the chip, but am concerned about a fellow Fiero owner.
Sorry about that - I didn't connect your payment together with this post and was going to send an email and ask. I was busy getting things ready to fly out to Virginia Friday to pick up a GT and drive it back. Things went well and the GT is sitting in my driveway and now I am getting to these backed up things. It will be in Monday's mail.
Would there be any advantage to swapping my California ECM PROM for a Federal ECM PROM?
The reason I ask is that my new to me 88 GT automatic just seems a bit sluggish compared to what I have had in the past as far as performance. My 2nd Formula was a California car, automatic, but just seemed to have more life to it. Yeah, I know the automatic will be a dog no matter what, but I am limited to that due to left leg issues.... stupid (but my best friend no matter what) dog and I had a race 3 years ago..... he won, I lost. heheheh....
My '88 GT began life in California, so as of right now I am assuming it still has the original ECM PROM in it. The federal PROM ECM number is AKYM3437. The California PROM ECM number is AKYR3452.
If there is a difference in performance, I would sure love to do the swap!
I am really curious as to the differences either way if anybody has that information.
If there is a difference, and someone has one, I would be very interested and will post a wanted in the mall.
Much appreciated! railshot a.k.a. Dave
Check the tag on your transmission, it should be near the odometer sender on the passenger end of the car, I belive it's on the back (rear) side of the tranny. It should read CPC which corresponds to the 3.33 final drive and 2095 rpm stall converter (code FDAB). Anything different is a good indication the transmission has been replaced likely with a trans that has a less performance oriented final drive and converter. 85-86 V6 autos received the 3.06 final drive and 2060 rpm stall coverter according to my ATSG transmission manual. The 4 cyl has a 2.84 final drive and I believe more often than not the focus is on the donor car and not so much the gearing on cars like ours during remanufactured transmission replacements since the ECM can't tell the difference in most cases with the 80s 3 speeds.
Check the tag on your transmission, it should be near the odometer sender on the passenger end of the car, I belive it's on the back (rear) side of the tranny. It should read CPC which corresponds to the 3.33 final drive and 2095 rpm stall converter (code FDAB). Anything different is a good indication the transmission has been replaced likely with a trans that has a less performance oriented final drive and converter. 85-86 V6 autos received the 3.06 final drive and 2060 rpm stall coverter according to my ATSG transmission manual. The 4 cyl has a 2.84 final drive and I believe more often than not the focus is on the donor car and not so much the gearing on cars like ours during remanufactured transmission replacements since the ECM can't tell the difference in most cases with the 80s 3 speeds.
Thanks Joseph Upson,
I forgot about this little bit of information actually. When I first purchased the car the original owner told me in an email ... "I put in 32/38 gears in the tranny". She does run at a pretty low rpm at 70mph, right around 2300 or so. That is probably the difference I am feeling, and why I can average 30 mpg on the highway, and around 25 all the time. Now it all makes sense.
I forgot about this little bit of information actually. When I first purchased the car the original owner told me in an email ... "I put in 32/38 gears in the tranny". She does run at a pretty low rpm at 70mph, right around 2300 or so. That is probably the difference I am feeling, and why I can average 30 mpg on the highway, and around 25 all the time. Now it all makes sense.
That's outstanding for a 3 speed as normally the sprocket ratio is 1 to 1 (35 to 35) for the V6. I thought about this because I drove someone elses V6 auto and it was very sluggish compared to my 4 speed manual and 3 speed auto. The 4 speed ran about 3200 rpm on the interstate if I recall correctly so you definitely have some overdrive going on there.
I know I'm reviving an old thread, but it's so closely related to my questions that I thought it better to post here than to start a new one...
I've had my 88 GT auto for about two years now. It was in pretty sorry running shape when I got it, and in the course of tuning it I discovered that it also had an '88 California EPROM - AKYR3452. While trying to get it to run decently, I came across an 87 GT auto in a yard, so I bought the ECM, with EPROM FBA1819, and swapped the EPROM, figuring that if there was any significant difference in performance, it would favor the federal chip (especially since I'm at altitude here in CO). It was after that and about 17 other repairs and corrections that the car runs as well as I expect it to with a stock drivetrain and an aftermarket cat and Ocelot exhaust. I "fast passed" the Colorado I/M 240 emission tests (very good numbers) with this combination and premium E10 (91 octane here, more or less equivalent to 93 at sea level) and about 13* BTDC base timing (SOTP dyno indicates this is better than the 87 octane mid-grade here with 10* BTDC).
I can't see the images phonedawgz posted earlier in this thread. So my questions are:
What are the differences between the 88 California vs 88 Federal EPROMs? What are the differences between the 88 and 87 Federal EPROMS? Should I be looking for an 88 EPROM? Custom EPROM?
My current combination runs pretty decently above about 1800 rpm, but not as responsive below that. Has me wondering if the timing is a little lazy down low...
I do not believe that the problem of soft low end torque is the chip but rather the 30 yr old engine in your Fiero. Wear will decrease the efficiency of any engine, Compression goes down, cam lobes wear, the CAT begins to clog (and become restrictive) , carbon builds up and the ignition even deteriorates.
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
I realize that we're talking about a 30-year-old engine, but compression is good, and regarding the cat, I replaced that last year with a Walker 15026, which flows considerably better than the original pellet bed type. The ignition includes a new distributor, plugs, wires, coil, ICM. Also new injectors, water pump, timing chain, alternator - basically everything that isn't the long block. I know that the 2.8L V6 is no torque monster (that's why a 3.4 is in my GT's future). Just wondering if I've optimized everything I currently do have, particularly because I have an 87 EPROM in an 88 car, and evidently the 88 EPROM is different, at least in part number.
