Gen V 5.3 L83 / 8L90e / Blackbox / 80series (1 Viewer)

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Correct, both stock and no BCM. I kind of figured I would need a simple switch, just not sure which pin in the harness and what that signal is (ground, positive, ??)

Thanks!
That I am not 100% sure of. I have a gen5 harness guy that did my electronic side. I’ll ask him tonight and get back with you.
 
Okay, thank you. I guess I will try to get information out of a harness builder, but I doubt they will be willing to divulge info without $$ transferring hands.
 
Yes the GM ECM will pick up speed internally from the transmission. I will try and drive the Toyota tach with the GM output and try adjusting the output with HPtuners. If that doesn't work I'll use a Dakota box.

Fuel I'm using a 240lph pump in the tank and the Corvette style regulator for 58psi. Then GenV motors run fine on 58 it's just less efficient for the pump. Maybe someday I'll convert to a fuel pressure controller and a PWM pump like factory.

If you mean the Corvette fuel filter / internal FPR - just a suggestion & plumb in a FP gauge on the output (not positive what Dakota wil do/throw signals on) - I had a ‘lean run‘ -warning on a Murphy box for my LS3 after a fuel filter swap.

Yuuuup, it was fixed w/ a 2nd fresh filter swap. A simple fresh fuel filter might have burned my LS3 / def wouldn’t have been good.

:confused:
 
If you mean the Corvette fuel filter / internal FPR - just a suggestion & plumb in a FP gauge on the output (not positive what Dakota wil do/throw signals on) - I had a ‘lean run‘ -warning on a Murphy box for my LS3 after a fuel filter swap.

Yuuuup, it was fixed w/ a 2nd fresh filter swap. A simple fresh fuel filter might have burned my LS3 / def wouldn’t have been good.

:confused:
Yes the quality of the Corvette FPRs tend to vary widely! I've run a gauge and seen a 10psi swing both ways for out of the box regulators. I check it after install and if it's too far out swap it. I prefer to have something available at any auto parts store vs an aftermarket part if it fails.
 
How's the swap coming along?

I'm almost done with mine. Having issues trying to source a lower rad hose. I reused the factory radiator.

Did you finalize cooling?
 
How's the swap coming along?

I'm almost done with mine. Having issues trying to source a lower rad hose. I reused the factory radiator.

Did you finalize cooling?
Gates 20230. It’s a upper radiator hose for a Ford Explorer.

Pic on my swapped 80:

1637887242875.jpeg
 
Gates 20230. It’s a upper radiator hose for a Ford Explorer.

Pic on my swapped 80:

View attachment 2848273
Not sure that will work on a gen5 L83 motor unless you adapt to the older style water pump or the very new L84 style pump.

No update on the swap. We used adapters and an LS2 pump with aftermarket radiator though. That hose should work for us with the Gen3/4 style pumps.
 
Just wanted to let you know that my swap is complete and i've been driving it for the last 2 months. Such a nice swap when all is said and done.

The truck drives great! not happy with the mileage. My 105 came with 4:30 gears and I only have 33s under it. So it's going through the gears a lot faster.

I will be swapping in 4:10s to see how the mileage improves.

for cooling, I ended up using a GM truck hose for a newer Tahoe. The upper was a generic, not sure what car it came out of.

in regards to temps in Saudi where it's currently in the mid 40s C. I'm seeing 83c when driving normal and if I hotrod it, it gets up to 98c.

Trans never got above 140F (it reads in F because my scangauge will only display F for trans).

Reach out if you need help. If you haven't finished yours yet, you better hurry. It's a great swap!
 
I have some questions , I currently have Tors old BJ73 LS3 swapped rig . The 6l80e is giving me the shutters , so it need to be replaced . I was wondering how hard and what I would need to swap in a 8L90e ? I just read the T case should mate up since it’s running a adapter and 80 series T case. I’m assuming I would need the trans harness and control unit . Is there anything else I might run up against ? Thanks for any input .
 
The LS3 works best with the 6L80, the gen V engines are made to work with the 8 and 10 speeds better. The computer languages are basically different, meaning it’s just more efficient for them to match. There were a few Gen V engines that used the 6 speed transmissions but mainly the 6 liter in the 3/4 ton trucks. I bet your shudder problem is fluid/filter based. If you want, I can give you the contact info to the guy that built that trans you have. PM me
 
The LS3 works best with the 6L80, the gen V engines are made to work with the 8 and 10 speeds better. The computer languages are basically different, meaning it’s just more efficient for them to match. There were a few Gen V engines that used the 6 speed transmissions but mainly the 6 liter in the 3/4 ton trucks. I bet your shudder problem is fluid/filter based. If you want, I can give you the contact info to the guy that built that trans you have. PM me
What he said, I don’t think a Gen4 ECU, what you have, will talk to a Gen5 transmission. Fluid, filter or possibly the torque converter. Talk to the guy who built it and see if he updated the pump sealing rings to the 2009+ style, the older ones caused a shudder on the 1-2 shift.
 
Solid build. Very interesting having a doubler as the adapter. I am looking forward to a follow up on the drive ability.
 
I have some questions , I currently have Tors old BJ73 LS3 swapped rig . The 6l80e is giving me the shutters , so it need to be replaced . I was wondering how hard and what I would need to swap in a 8L90e ? I just read the T case should mate up since it’s running a adapter and 80 series T case. I’m assuming I would need the trans harness and control unit . Is there anything else I might run up against ? Thanks for any input .

I've been researching the 6L80 to 8L90 swap as well. I found this video regarding the input and bellhousing along with the overall size but no mention on output splines or if the 8l90 would take the marks adapter? Have you found info on this?

You could run the LS with 8l90 but using a non GM ECM. I think Holley has something for this.

I'd like to move into an 8 speed. It's been almost 2 years since I swapped mine. Love the drivetrain. I'm just having an annoying issue where the car will not start immediately. It's due to fuel pressure drop when the car is off. I have to prime it (leave ignition on for a second or two) then it can start. I think it's bleeding the fuel to the return line at the regulator. Besides that, I'd love to get more range out of it. I'm sure it can be tuned to do so.
 
I've been researching the 6L80 to 8L90 swap as well. I found this video regarding the input and bellhousing along with the overall size but no mention on output splines or if the 8l90 would take the marks adapter? Have you found info on this?

You could run the LS with 8l90 but using a non GM ECM. I think Holley has something for this.

I'd like to move into an 8 speed. It's been almost 2 years since I swapped mine. Love the drivetrain. I'm just having an annoying issue where the car will not start immediately. It's due to fuel pressure drop when the car is off. I have to prime it (leave ignition on for a second or two) then it can start. I think it's bleeding the fuel to the return line at the regulator. Besides that, I'd love to get more range out of it. I'm sure it can be tuned to do so.
Have a tuner change the priming time from 2 seconds to maybe 3 or 4 to refill the line.
 
Have a tuner change the priming time from 2 seconds to maybe 3 or 4 to refill the line.

It's priming up to 4 seconds no issue. I just don't know why it looses pressure when the car is off. once I shut it off, it immediatly looses pressure. I have a gauge on the regulator. You can see it drop pressure. O.E applications, usually holds for a few hours before it starts to bleed off.

I can't do a one way valve. It would block the return.

How is yours coming along?
 
Dave from Torfab. We have an adapter launching for the GenV to 80 series Transfer case. Price will be $2630 with free shipping.

We will be offering this as a kit which will allow you to bolt in a 6.2/5.3L LT motor into an 80 series in the factory engine mount location without any modifications to the drivelines or need for welding on the Toyota frame. With our adapter kit you keep the engine/trans into the stock frame brackets and stock t-case crossmember, and also allows the stock drivelines to be used. This simplifies your engine placement and location mounting with out needing to worry about drivelines and make it a bolt in process.

The kit will include:

  • * OEM Toyota Engine Mounts
  • * Engine mount adapter brackets (mounts to the LT motor and allows Toyota 80 series engine mounts to bolt in factory frame location)
  • * Torfab Adapter for the GM Trans to HF2A transfer case
  • * Transmission shifter linkage (this will adapt the 8/10 speed transmission to your stock 80 Transmission Shift Lever (P-R-N-D-2-L)
  • * Transfer case shifter adapter bracket. (This bracket allows you to mount the early 80 transfer shift lever to the GM transmission in the stock location without modifying the body.)
The kit will require the following:

  • * Early 80 (91-94) transfer case shifter base (retainer and shaft). If you have a 95-97 you will need to source this part. PN: 36344-60021
  • * Factory adapter/extension housing from A343 transmission 1995-1997 and 6 mounting bolts (this can be used from old drivetrain or source a used one). PN: 35015-60070
  • * GM LT Motor L83/ L84/ L86/ L87
  • * Factory GM 4WD 8 or 10 speed transmission (8L90 or 10L90)
  • * HF2A Transfer case
IMG_2456.jpg
Screenshot 2022-12-06 143309.jpg
 
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It's priming up to 4 seconds no issue. I just don't know why it looses pressure when the car is off. once I shut it off, it immediatly looses pressure. I have a gauge on the regulator. You can see it drop pressure. O.E applications, usually holds for a few hours before it starts to bleed off.

I can't do a one way valve. It would block the return.

How is yours coming along?
Is your regulator after the fuel rails? If it’s before in-line they tend to bleed down less with a corvette style. I have an after the rail regulator on my hot rod and it has the same issue. I don’t have the 80 project anymore. I might do a gen5 L86 in Mt FJ45 but will be a 6l90 trans since I don’t have an 8l90 or 10l to play with.
 
Dave from Torfab. We have an adapter launching for the GenV to 80 series Transfer case. Price will be $2630 with free shipping.

We will be offering this as a kit which will allow you to bolt in a 6.2/5.3L LT motor into an 80 series in the factory engine mount location without any modifications to the drivelines or need for welding on the Toyota frame. With our adapter kit you keep the engine/trans into the stock frame brackets and stock t-case crossmember, and also allows the stock drivelines to be used. This simplifies your engine placement and location mounting with out needing to worry about drivelines and make it a bolt in process.

The kit will include:

  • * OEM Toyota Engine Mounts
  • * Engine mount adapter brackets (mounts to the LT motor and allows Toyota 80 series engine mounts to bolt in factory frame location)
  • * Torfab Adapter for the GM Trans to HF2A transfer case
  • * Transmission shifter linkage (this will adapt the 8/10 speed transmission to your stock 80 Transmission Shift Lever (P-R-N-D-2-L)
  • * Transfer case shifter adapter bracket. (This bracket allows you to mount the early 80 transfer shift lever to the GM transmission in the stock location without modifying the body.)
The kit will require the following:

  • * Early 80 (91-94) transfer case shifter base (retainer and shaft). If you have a 95-97 you will need to source this part. PN: 36344-60021
  • * Factory adapter/extension housing from A343 transmission 1995-1997 and 6 mounting bolts (this can be used from old drivetrain or source a used one). PN: 35015-60070
  • * GM LT Motor L83/ L84/ L86/ L87
  • * Factory GM 4WD 8 or 10 speed transmission (8L90 or 10L80)
  • * HF2A Transfer case

Dave, this is great news for those who want a simple and easy way to swap an LT into their cruiser. Just to let you know, it's exactly the same for those who have a 105 cruiser. So your kit should work on both chassis as they are identical for the most part.

do you know if the 6l80 and 8l90 have the same output? So can your Tcase adapter fit either transmission?


Is your regulator after the fuel rails? If it’s before in-line they tend to bleed down less with a corvette style. I have an after the rail regulator on my hot rod and it has the same issue. I don’t have the 80 project anymore. I might do a gen5 L86 in Mt FJ45 but will be a 6l90 trans since I don’t have an 8l90 or 10l to play with.

Ah too bad. I thought you'd have it running by now. The 45 will be fun for sure!

I kept the stock L83 fuel rail and it's non return. So the regulator is pre fuel-rail. I'm using this regulator


I think If I did a return-less fuel system it could act more like O.E?
 

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