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View Full Version : 1995 Silverado tpi and 4l60e trans swap



dusterbd13
10-24-2020, 02:28 PM
So, one thread for two different thought processes.

First and foremost is transmission.
It seems that the 1995 gmt400 truck 4l60e is a one year only thing. Mines giving signs that its on the way out. Local yard has tons of 4l60e and 4l80e with warranty for $400. Except no 95. Its my understanding that its a difference in the valve body and how the electronics work. Is there a .bin or something that makes it a feasible swap with factory tuning and reliability? If so, what years and versions?

Secondly, good friend has a 89 Corvette tpi system laying around. Just intake, throttle body, injectors, and a few sensors. I remember my 88 vette was a fantastically torquey engine with decent fuel mileage. Is there a well sorted tune to do a tpi swap with an e trans? Any leads on a write up?

Thanks guys. Been out of obd1 gm stuff for so long i dont remember any of it (getting the 64 elky t boned and some head trauma probably didn't help either)

tayto
10-24-2020, 05:23 PM
Do some googling on this. Not sure about trucks, but the 94-96 B-bodies this is covered quite well. The earlier 4L60Es will not work but I think you can use a 96/97 and just swap the 95 valve body. Keep in mind in 98 they went to a different style case. Not sure I would waste time with a used 4L60E unless there's documents to support it was rebuilt recently. I would opt for rebuilding YOUR 4L60E. I would opt for a reputable online vendor (Probuilt Automatics) even after almost 30 years the local guys still can't seem to get it right (my experience).

https://www.impalassforum.com/threads/4l60e-swap-guide-b-body.232098/

TPI with your TBI heads will be an excellent combo for low end torque. I believe Fast355 did this swap over a decade ago on TGO. I also believe your PCM can be modified to be setup in batch fire mode (same as the TPI ecu).
https://www.gmt400.com/threads/tbi-to-tpi-conversion-mpfi.39486/

Neukam
10-24-2020, 06:31 PM
The 16197427 PCM can be set up to work with the 93-94 trans or the 95 trans and can also be set up to work with mpfi. Perhaps someone here can help you set up a bin to work with the TPI and either your 95 trans if you decide to get it rebuilt, or a 93-94 trans if you find one. You could also use a 96 or later trans with an 0411 PCM or black box PCM, but you would have to add a crank sensor and a Vortec distributor.

THEFERMANATOR
10-24-2020, 11:27 PM
93/94 is the 1st gen 4l60e, 95 added a pwm solenoid to the torque converter clutch control circuit so they could apply it slower so lockup didn't feel like another shift. 96 changed the 3-2 downshift solenoid from a normally closed to a normally open solenoid and reversed the 3-2 downshift valves operation to match. A 7427 was used from 93-95, so you can easily make a 93/94 style or a 95 style 4l60e work with the correct base file. And moi has been done on the 7427. Just keep in mind your 95 has swirl port heads and make alot of bottom end torque due to the swirl port intake design, the tpi intake makes tons of bottom end torque due to the long runners and large plenum. The 2 mixxed together will make for a low rpm torque machine.

In-Tech
10-25-2020, 12:00 AM
93/94 is the 1st gen 4l60e, 95 added a pwm solenoid to the torque converter clutch control circuit so they could apply it slower so lockup didn't feel like another shift. 96 changed the 3-2 downshift solenoid from a normally closed to a normally open solenoid and reversed the 3-2 downshift valves operation to match. A 7427 was used from 93-95, so you can easily make a 93/94 style or a 95 style 4l60e work with the correct base file. And moi has been done on the 7427. Just keep in mind your 95 has swirl port heads and make alot of bottom end torque due to the swirl port intake design, the tpi intake makes tons of bottom end torque due to the long runners and large plenum. The 2 mixxed together will make for a low rpm torque machine.
I wish I could have said it better :) great reply. The trucks should have had the tuned port for the incredible torque that a truck needed.

dusterbd13
10-25-2020, 11:43 PM
Do some googling on this. Not sure about trucks, but the 94-96 B-bodies this is covered quite well. The earlier 4L60Es will not work but I think you can use a 96/97 and just swap the 95 valve body. Keep in mind in 98 they went to a different style case. Not sure I would waste time with a used 4L60E unless there's documents to support it was rebuilt recently. I would opt for rebuilding YOUR 4L60E. I would opt for a reputable online vendor (Probuilt Automatics) even after almost 30 years the local guys still can't seem to get it right (my experience).

https://www.impalassforum.com/threads/4l60e-swap-guide-b-body.232098/

TPI with your TBI heads will be an excellent combo for low end torque. I believe Fast355 did this swap over a decade ago on TGO. I also believe your PCM can be modified to be setup in batch fire mode (same as the TPI ecu).
https://www.gmt400.com/threads/tbi-to-tpi-conversion-mpfi.39486/


problem with google is i couldnt figure out what to search to get the information i was looking for! one of the joys.....

also, that write up in GMT400 is bang on! thanks!

dusterbd13
10-25-2020, 11:55 PM
93/94 is the 1st gen 4l60e, 95 added a pwm solenoid to the torque converter clutch control circuit so they could apply it slower so lockup didn't feel like another shift. 96 changed the 3-2 downshift solenoid from a normally closed to a normally open solenoid and reversed the 3-2 downshift valves operation to match. A 7427 was used from 93-95, so you can easily make a 93/94 style or a 95 style 4l60e work with the correct base file. And moi has been done on the 7427. Just keep in mind your 95 has swirl port heads and make alot of bottom end torque due to the swirl port intake design, the tpi intake makes tons of bottom end torque due to the long runners and large plenum. The 2 mixxed together will make for a low rpm torque machine.

the idea behind tpi is increased MPG, as well as all the low end torque i can get. its a truck, that i use for truck stuff. primarily open car trailer, tow dolly, etc. i found the tbi 350 in my other 95 is kinda gutless pulling uphill with a car on the dolly.
thanks for tripling the available trannys! any further reading i can do about the ecu changes or other differences id need to be aware of? unfortunately, i believe the failure of my trans is the valve body, but i have no way to confirm this. not even remotely familiar or comfortable going any further in a tranny than a filter.

stew86MCSS396
10-26-2020, 11:15 AM
If it was all i had laying in the shed and didnt want to spend anymore money than necessary, i wouldnt hesitate to elongate 4 center holes on the intake manifold. Also if you gotta have egr, Vette intake uses external plumbing from intake to exhaust. Just couple of things to look out for.
https://www.hotrod.com/uploads/sites/21/2013/04/hrdp-1304-01-late-350-chevy-tbi-heads-on-a-carbureted-70s-short-block-cast-iron-heads1.jpg?fit=around%7C875:492

lionelhutz
10-26-2020, 10:56 PM
I don't know on the truck PCM, but I'm running a 96 4L60e with a 95 computer just fine in a LT1.

dfarr67
10-29-2020, 07:01 PM
- I've got something similar only older:
-- rebuild your trans with needed upgrades- these aren't a 'robust' transmission, so 94/95 issue problem solved.
-- center head bolts not really an issue after slotting, your ecu will work great for what you want, or go EBL.

tayto
10-29-2020, 09:57 PM
EBL will not control the E trans. 1996+ are considered the "better years" as far as the 4L60E is concerned.

OP, please keep us updated with this swap. A lot of the TBI to TPI swaps that have been done are missing pictures/info and are using a '730 with non e-trans control. I am interested in doing this swap one day as well. good luck!

dfarr67
10-30-2020, 12:52 AM
16185

You are right about the EBL- I have a 700R right now and will be moving to the last gen one piece case 4x4 4L60E next year with the 0411 ecu.

tayto
10-30-2020, 02:00 AM
can you post more details & pics of your air intake? looks like you reused the factory fender cold air intake. (i like)

dfarr67
10-30-2020, 03:50 PM
Roughly- its been a long time.
- Firebird 90 deg TB boot.
- GMT400 diesel air filter housing, made tube between to fit between.
- 385cid, AFR vortec, FIRST TPI- w oem TB, injector rails.
- batch fired injection based off of oem 7747 harness, next year hopefully LS cnp, 0411 ecu/harness.