1991 Grand Am 3800 Swap
#11
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personally i would just fix the bonnie, they are a ton more room, easier to fix and less break downs than a GA, goes on an on. on a GA you have to take off 5 other things before you get to what you are working on. bonnie you can get to most anything.
#12
Retired
Megasquirt controllers are for track/off road use only. EPA does not allow them for on-road use.
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#13
Senior Member
True Car Nut
maybe so but on a obd1 not likely going to be noticed. if you put it under the dash like most of the other oem pcms there would be no suspicion. i think if you had the cat still you would be good with inspections
#14
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I wasn't aware of that, Mike. Regardless, I live in Iowa... I've never had an emissions test. Honestly, I think I would have a hard time thinking of anyone I know who has. As far as I'm aware, we don't even have them in Des Moines. My car already has the cat removed, so I'm not terribly concerned with emissions compliance.
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I know you folks don't know why I'm interested this swap, but it'* still an intriguing idea to me. I've been doing a lot more research, trying to figure out how it would all go together. From what I discovered, the '94-95 3800 S2 uses an OBD1 PCM. The Fiero swap guys use that sometimes.
The one thing that bugs me is the trans control issue. A friend of mine (the one selling me the Bonne, actually) told me that I should use a 4T65E if I do this swap. He says that the 4T60E wouldn't last behind an L67. From a mechanical standpoint, it still seems like a solid plan. The 4T60, 4T60E, and 4T65E all use the same axle shafts (also learned that on a Fiero forum), so the axle shafts from a '94-98 3100/4T60E Grand Am should fit the 4T65E, and the engine of course bolts directly to the L67, as it'* the factory trans. However, it would not work with the OBD1 computer. One option is to use a trans controller, but the cheapest I've found is $650. I am considering that, though, the result is worth it to me. This is the first option, OBD1 PCM, standalone TCU.
My second option, which I don't know can be done, is to use the OBD2 computer for the engine and trans and somehow connect it to the car. I haven't been able to find much info on this. The Fiero guys do it, but there isn't much mention as to how it all works with the gauge panel, and I don't know if there is any carryover at all to the application of my Grand Am.
The third option is to use the OBD1 PCM with the 4T60E it was intended for. I don't like this idea at all, because I'd prefer to have the beefier 4T65E.
So, there it is. I'm still set on doing this swap if at all possible. I like that body style of Grand Am, and the car has really grown on me, but I want a 3800 Series 2. It'* just my personal preference. So what do you all think? Is there any way to pull it off without a standalone TCU?
The one thing that bugs me is the trans control issue. A friend of mine (the one selling me the Bonne, actually) told me that I should use a 4T65E if I do this swap. He says that the 4T60E wouldn't last behind an L67. From a mechanical standpoint, it still seems like a solid plan. The 4T60, 4T60E, and 4T65E all use the same axle shafts (also learned that on a Fiero forum), so the axle shafts from a '94-98 3100/4T60E Grand Am should fit the 4T65E, and the engine of course bolts directly to the L67, as it'* the factory trans. However, it would not work with the OBD1 computer. One option is to use a trans controller, but the cheapest I've found is $650. I am considering that, though, the result is worth it to me. This is the first option, OBD1 PCM, standalone TCU.
My second option, which I don't know can be done, is to use the OBD2 computer for the engine and trans and somehow connect it to the car. I haven't been able to find much info on this. The Fiero guys do it, but there isn't much mention as to how it all works with the gauge panel, and I don't know if there is any carryover at all to the application of my Grand Am.
The third option is to use the OBD1 PCM with the 4T60E it was intended for. I don't like this idea at all, because I'd prefer to have the beefier 4T65E.
So, there it is. I'm still set on doing this swap if at all possible. I like that body style of Grand Am, and the car has really grown on me, but I want a 3800 Series 2. It'* just my personal preference. So what do you all think? Is there any way to pull it off without a standalone TCU?
#16
Senior Member
It can be done as stated above, you just need to send in the L67pcm and have the security, Evap and Traction control options turned off. And I would use what ever trans came in the Bonnie because its already set up with the L67 PCM, if the 4t60 lasted in the Bonnie it will last in the lighter grand am. You would just need to make a custom dash with manual gauges and use a GPS speedo. Also you are going to need to make motor mounts for the 3.8. If your willing to spend more than the car is worth on programing and trinkets I say have at it if you have the tools and time.
#17
Senior Member
True Car Nut
you can do the manual gauges or since its going to be obd2 you can use one of the obd2 bluetooth apps. like the one i use "torque pro" for android tablet or phone, has a function where you can display a number of engine parameters, tach, and speed from the pcm.
#18
Retired
Last I knew, no such thing as a 94 Series 2. Series 2 engines came out in 1995 and they were OBD 1.5 compliant. And pretty close to OBD2 compliant. 1994 and prior was Series 1.
4T60 is a non-electronic trans. The 4T60-E is. If you can find the rare 1996 4T60-E-HD, you will be fine.
A separate trans controller? Good luck. If this was a 1960 pickup and you were putting an LS9 with a 6L80-E in it, then yea it would be possible. Because their is actually a market for setups like this. Nobody made custom kits like this for gramma 1994 cars.
As he mentioned above, unless you have a programmer to make changes to the OBD 2 software, the PCM is going to have a serious hissy fit in a OBD1 environment. Just because the trans and engine is compatible with the PCM, doesn't make it compatible with the car.
Take for instance. My 1995 Bonneville OBD 1.5, the fuel gauge was wired directly to the sending unit in the tank. 1996, the PCM now handles the fuel sending unit taking the fuel level and sending it to the cluster. As many other things in 1996 and higher, everything is handled from the PCM or BCM, THEN sent to the cluster. Even some HVAC controllers need to talk to the PCM AND instrument cluster. None of this is going to happen in a 94 chassis.
Go get a subscription to Alldata and pull the PCM wiring diagrams for both PCM'*. Now you will see the nightmare upon you.
4T60 is a non-electronic trans. The 4T60-E is. If you can find the rare 1996 4T60-E-HD, you will be fine.
A separate trans controller? Good luck. If this was a 1960 pickup and you were putting an LS9 with a 6L80-E in it, then yea it would be possible. Because their is actually a market for setups like this. Nobody made custom kits like this for gramma 1994 cars.
As he mentioned above, unless you have a programmer to make changes to the OBD 2 software, the PCM is going to have a serious hissy fit in a OBD1 environment. Just because the trans and engine is compatible with the PCM, doesn't make it compatible with the car.
Take for instance. My 1995 Bonneville OBD 1.5, the fuel gauge was wired directly to the sending unit in the tank. 1996, the PCM now handles the fuel sending unit taking the fuel level and sending it to the cluster. As many other things in 1996 and higher, everything is handled from the PCM or BCM, THEN sent to the cluster. Even some HVAC controllers need to talk to the PCM AND instrument cluster. None of this is going to happen in a 94 chassis.
Go get a subscription to Alldata and pull the PCM wiring diagrams for both PCM'*. Now you will see the nightmare upon you.
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#19
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he never said what year it actually was which would greatly help with the guessing, it could be anywhere from a complete PITA to not so bad.
being a 91 GA most all the hvac and sub systems are not likely spidered together like the newer cars and should be fairly easy to make work
being a 91 GA most all the hvac and sub systems are not likely spidered together like the newer cars and should be fairly easy to make work
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Last I knew, no such thing as a 94 Series 2. Series 2 engines came out in 1995 and they were OBD 1.5 compliant. And pretty close to OBD2 compliant. 1994 and prior was Series 1.
4T60 is a non-electronic trans. The 4T60-E is. If you can find the rare 1996 4T60-E-HD, you will be fine.
A separate trans controller? Good luck. If this was a 1960 pickup and you were putting an LS9 with a 6L80-E in it, then yea it would be possible. Because their is actually a market for setups like this. Nobody made custom kits like this for gramma 1994 cars.
As he mentioned above, unless you have a programmer to make changes to the OBD 2 software, the PCM is going to have a serious hissy fit in a OBD1 environment. Just because the trans and engine is compatible with the PCM, doesn't make it compatible with the car.
Take for instance. My 1995 Bonneville OBD 1.5, the fuel gauge was wired directly to the sending unit in the tank. 1996, the PCM now handles the fuel sending unit taking the fuel level and sending it to the cluster. As many other things in 1996 and higher, everything is handled from the PCM or BCM, THEN sent to the cluster. Even some HVAC controllers need to talk to the PCM AND instrument cluster. None of this is going to happen in a 94 chassis.
Go get a subscription to Alldata and pull the PCM wiring diagrams for both PCM'*. Now you will see the nightmare upon you.
4T60 is a non-electronic trans. The 4T60-E is. If you can find the rare 1996 4T60-E-HD, you will be fine.
A separate trans controller? Good luck. If this was a 1960 pickup and you were putting an LS9 with a 6L80-E in it, then yea it would be possible. Because their is actually a market for setups like this. Nobody made custom kits like this for gramma 1994 cars.
As he mentioned above, unless you have a programmer to make changes to the OBD 2 software, the PCM is going to have a serious hissy fit in a OBD1 environment. Just because the trans and engine is compatible with the PCM, doesn't make it compatible with the car.
Take for instance. My 1995 Bonneville OBD 1.5, the fuel gauge was wired directly to the sending unit in the tank. 1996, the PCM now handles the fuel sending unit taking the fuel level and sending it to the cluster. As many other things in 1996 and higher, everything is handled from the PCM or BCM, THEN sent to the cluster. Even some HVAC controllers need to talk to the PCM AND instrument cluster. None of this is going to happen in a 94 chassis.
Go get a subscription to Alldata and pull the PCM wiring diagrams for both PCM'*. Now you will see the nightmare upon you.
I did say 4T60E, not 4T60. I know it'* non-electric. I only mentioned it to state that it uses the same axles.
As for the trans controller, there are a few threads on the Fiero forum as to which trans controller to use with a 4T65E, and there are quite a few options.
I still want to retain my gauge cluster, but if I went the OBD2 route, I don't know why a gauge swap from the Bonneville wouldn't work..? If all that need to communicate are the gauge cluster, engine, trans, and various sensors, why wouldn't a gauge cluster swap solve the problem?