Before automatic transmissions became electronically controlled, were there any differences between how ECMs were programmed for cars with manual and automatic transmissions?
And if you don't know the answer to this question for cars in general, do you know if there were any differences in ECM programming between manual and automatic Fieros?
Fieros--Yes, there was a difference in auto and manual equipped ECM programming. An auto ECM will operate efficiently in a manual equipped car but the manual won't operate properly in the auto equipped car due to the rpm bump up required by automatics when it's pulled into gear. A manual will let the engine stall.
Other non-electronic transmissions like the 4T60 will operate in the Fiero, using the Fiero automatic programmed ECM. Probably any other non-electronic transmission that doesn't use a vacuum servo will also work when bolted to the Fiero engine.
Am I to understand that, say I decide to swap my TH125C for an Isuzu 5-speed or an F40 6-speed, my automatic ECM will work fine?
Can the same thing be said for, say, the pre-electronic automatic versions of the Cadillac aluminum-block V8? Their ECMs will work fine with manual transmissions without being reprogrammed?
I am not personally familiar with the Cadillac trans so I don't know how that would work unless it's the 4T60. Many have posted on this forum that it's the transmission to use when you don't want to piggyback an engine controller ECM and a transmission controller ECM. The Fiero's automatic programmed ECM will work well with the manual transmissions unless they have sensor inputs to the ECM. The Isuzu doesn't but I don't know about the F40. The Fiero Isuzu, Muncie and Getrag transmissions, I've actually done some diagnostics using a Fiero ECM from an automatic and I had no problems.
Am I to understand that, say I decide to swap my TH125C for an Isuzu 5-speed or an F40 6-speed, my automatic ECM will work fine?
Can the same thing be said for, say, the pre-electronic automatic versions of the Cadillac aluminum-block V8? Their ECMs will work fine with manual transmissions without being reprogrammed?
You might get a check engine light because the ECM doesn't see the electrical load of the TCC/VCC present.
I would run the ECM that matches the engine and have the ECM reprogrammed to delete the transmission.
Same topic, new question: Say I have a stock 1996 LT1, with its original ECM, and a stock 4T65E-HD. How hard is it to reprogram the LT1's ECM to shift the 4T65E-HD, considering the fact that this transmission was never mated to that engine from the factory?
Depending on the year 4T65eHD the LT1 may or may not be able to generate the proper signals to activate the shift solenoids. I would say that with the sub 2003 trans that PCM might be able to shift it. Once electrical compatibility is established then transmission programming is possible. Sinister probably knows about the shift solenoids and which can be controlled by the LT 1 PCM. the LT4 PCM can shift those transmissions but you would run into other problems using it. Best approach might be a separate transmission controller.
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Flotech Afterburner Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, 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 "
[This message has been edited by Dennis LaGrua (edited 07-09-2015).]
Same topic, new question: Say I have a stock 1996 LT1, with its original ECM, and a stock 4T65E-HD. How hard is it to reprogram the LT1's ECM to shift the 4T65E-HD, considering the fact that this transmission was never mated to that engine from the factory?
If you really want a V8 with a 4t65e-HD, my suggestion would be to try and find an LS4 and just do that swap. They came from the factory with that trans, so if you just get an entire drop out and harness from a car with one, you'll be pretty much set in terms of electronics and mating the two together. It makes more power (than the F-body LT1 anyway), weighs less, and better MPG.
I know all about the LS4 and its 4T65E-HD, but a complete powertrain, ECM, and harness can be hard to find around these parts, not to mention expensive sometimes. However, I might be able to get a used V8 Archie kit at a good price, so I was wondering how I could keep my Fiero automatic but upgrading to a 4-speed instead of the TH125C. I know the non-electronic 4T60 is a possibility, but I'm afraid it might be too weak for the horsepower and torque of some SBCs.
[This message has been edited by Hidalgo (edited 07-09-2015).]
I know all about the LS4 and its 4T65E-HD, but a complete powertrain, ECM, and harness can be hard to find around these parts, not to mention expensive sometimes. However, I might be able to get a used V8 Archie kit at a good price, so I was wondering how I could keep my Fiero automatic but upgrading to a 4-speed instead of the TH125C. I know the non-electronic 4T60 is a possibility, but I'm afraid it might be too weak for the horsepower and torque of some SBCs.
Is the kit for a Gen I/II SBC with an auto? There's different kits for auto and manual, and the LSx kit is only available in manual.
There are also multiple levels for Archie's kits. If it's the base kit, you might still end up spending quite a lot on the rest of what is needed to complete the swap. I was just suggesting the LS4 option as maybe a way to get the best bang for your buck for a V8 swap. I don't know what the going rates are, or if you can even find one, where you are though.
If you don't need to go with a SBC V8, but want to stay automatic, then I might suggest going for a 3800 swap. They are much easier and cheaper than any SBC swap will be, and the Series II SC 3800 will make almost as much power as the lower power LT1 versions, and will make more than any of them, with some pretty minor mods. The swap and mods are all very well documented, and they can be had relatively cheap as there were so many of them.
Thanks for the suggestion, but my first Fiero was an 88 GT, and I performed a 3800 swap on it. It was great, but now I have a hankering for the sound and smoothness that can only come from V8 power.
I am aware of the different levels of Archie's kits. I believe the one I have my eye on is the Economy kit, so I would still need to get a 3-row radiator and custom exhaust elsewhere, among other things.
One thing I know less about, however, is which parts in Archie's kit change depending on the Gen of the SBC in question, aside from the flywheel that changes depending on the rear main seal. I assume the SBC electric water pump that comes with his kits won't fit on an LT1/L99, but what about the starter?
[This message has been edited by Hidalgo (edited 07-20-2015).]
Thanks for the suggestion, but my first Fiero was an 88 GT, and I performed a 3800 swap on it. It was great, but now I have a hankering for the sound and smoothness that can only come from V8 power.
I am aware of the different levels of Archie's kits. I think the one I have my eye on is the Deluxe kit, so I would still need to get a 3-row radiator and custom exhaust elsewhere, among other things.
One thing I know less about, however, is which parts in Archie's kit change depending on the Gen of the SBC in question, aside from the flywheel that changes depending on the rear main seal. I assume the SBC electric water pump that comes with his kits won't fit on an LT1/L99, but what about the starter?
I think the pump would be the same for the LT1/L99, but the fittings and such might be different. I don't know about the starter. I'd call or PM Archie and see what he has to say about the water pump and starter.
