Gen V Engine swap info

[vannatta20]

I started a thread on LS1tech and wanted to pass it on here to help anyone out doing this.

I would like to start a thread where we can all gather basic swap info into the new LT1, LT4, L86, and L83 engines. All the info given below is what I have experienced. I have about 3000 miles on the swap (2008 JK Wrangler) with no issues. So far I have done a few 6.2's and 5.3s. The 8 speed transmission is awesome and the 6 speed is great as well.


1. Fuel pressure requirements- So far the standard fuel pressure of around 57 psi works great. Fuel trims are dead on. Just make sure you have a pump that will support the engines power.

2. Programming- I used hptuners to delete vats and any DTC codes that showed up. Get the matching ECU and BCM from the donor vehicle. You will have issues programming a new OS and VIN if you do not. (BCM needed for transmission control and the brake pedal position sensor) This ECU has so many complex tables be careful of any changes you do. If you use GM SPS service you can not program off vehicle. You will need the ECU, TCU, and BCM at least to program. You most likely will not be able to change the VIN but it will program the new OS.

3. Transmissions- I have only used the matching 6l80e (six Speed) and 8l90e (8 speed) transmissions. Everything works including tap shift and power modes on the 6 speed. The 8 speed I don't have the tap shift working yet. The new transmissions really make this an awesome combo. I would stay away from using any other transmissions. The ECU are extremely complicated and to tune these is much different. With a matching drop out everything will work seamlessly. I did a L86 with a TH400 and it was a huge let down in drive-ability. The new transmissions shift lighting fast and are made to handle the power. Much better gear ratios. the 4.1 first gear is a tire shredder!

4. Accessory Drive- We just added a power steering pump on a truck layout. Holley will offer a kit soon. If using DOD/AFM you will need to keep the vacuum pump.

5. Wiring Harness- I modded the harness myself and is not too hard. Please recommend any companies that currently make custom harnesses. Having it modded will be by far the cheapest and quickest solution. The truck layout looks like a car layout now so it looks much better. The quality of the factory harness is much much better.

6. Fuel pump signal- This is now can bus driven. For now I can only think to use an ignition on for the fuel pump control. The Fuel pump control module is not needed.

7. Fan Control- You can use discrete or PWM. I am using PWM with awesome results. It controls the fan speed based on A/C pressure and ECT. PWM fans that can be used are from the new camaro and trucks.

8. Limp mode issues- I had no throttle without connecting the transmission computer up. If not using the matching transmission that came with the engine you will need to find a manual transmission tune. (If anyone finds a solution please post. GM's swap harness and ECU will not have this issue.Some of the computers do not allow the throttle to move until the engine is running. I see this on the Gen v 5.3. The gen v 6.2 will work without it running oddly.

9. DOD/AFM- It is highly active with the stock tune. At 65 mph it can be in 4 cylinder mode. Cruising around town it will kick in all the time. Its loud and annoying to be honest with loud exhaust. GM tuned the exhaust so you do not hear the change. For now I have it only working on steady cruises. Its not bad with quiet exhaust and makes a big difference in fuel economy. You need to run the GEN V Engine mounts if using DOD.

10. Engine Mounts- It is very important to use factory mounts if retaining AFM/DOD function. The mounts help absorb the extra vibrations. Please list any companies that make conversion mounts.

11. AC- The Factory GEN V AC compressor works great but it is a variable pump. This needs ignition power supplied to it and it will function fine.

12. Cruise Control
Only working so far with a aftermarket controller

On youtube check out the channel WranglerJKLS. Lots of videos with Gen V's running and driving.

[vannatta20]

13-Body Control Module

It is needed. This is mostly only needed for the brake pedal sensor, tap shift, power modes, and communicates with the ECU and TCU. It tells the transmission how much brake is applied and downshifts and rev matches accordingly. A tap shift switch can be installed as well but its uses multiplex signal and is complicated. The power mode is just a analog ground signal.

[68c10airstream]

I've had a little exposure to multiplexing switches in the late 90's.

Example, factory cruise has remote controls on steering wheel. 12volts"+" is available at the horn circuit and uses it as a power source. As you press the various buttons for cruise functions each button has a built in resistor. Lets say that you press the cruise "on" button. The built in resistor drops the available 12volts "+" to say 9.6 volts and that circuit goes to the cruise module. All of the cruise buttons are connected to one return wire back to the module. Anotherwords, every cruise switch has it's own predetermined voltage value. This system is called resistive multiplexing. One power source, one return, and many functions. The horn circuit is also used because who presses the horn while setting their cruise!!, and if the horn doesn't work, neither does the cruise, forcing you to fix a safety related system to get an accessory to work.

I listed this info to give you a glimpse into just one of the multiplexing systems out there and a fairly simple one. Good luck.

[bluetrim]

Thanks for posting this. I am trying to find out what it takes to do a GenV swap and hopefully we can get more vendors listed on this post who are selling parts for this swap.

[vannatta20]

If anyone is willing to be a test subject please PM me. I can help get everything you need but you need to be able to install the drive train on your own and figure out the mounts. I have a solution for power steering as well but it is not available for sale. It would be preferred if your close to Las Vegas, NV. I have the full GM network working so the transmission and engine work perfectly together. Tap shift will work as well if using the 6L80E. Tow/Haul will be programmed as a performance mode for quicker shifts and high RPM shifting. I have about 5 Gen V swaps completed so far but non in a 67-72 C10. Doing one now in a 1952 Chevy Pickup.

[87chevy.com]

You might not have all the right information... the BcM is not required, only if you want tap up and tap down and how haul.. but spear tech makes a kit. If you use the bcm it does not need a multiplex switch.. It's simply a momentary ground through a set of resistors.

The 57 psi might work, gmpp clearly states 72 psi...

From the first l83 swap discrete setting didn't work.. would not send ground output didn't spend a lot of time on it... going to look into it on my swap. But discrete is the correct setting for on/off output according to hp tuners documents.

I'm building harness', currently on my 2nd one.

Clint

[87chevy.com]

Originally Posted by vannatta20

6. Fuel pump signal- This is now can bus driven. For now I can only think to use an ignition on for the fuel pump control. The Fuel pump control module is not needed.

From the GMPP install on the GEN V

This control system is intended for use with a returnless fuel system and fuel pump that is capable of being pulse width
modulated (PWM) at 25 kHz to control fuel pressure. A fuel flow rate of 45 gph at 72 psi (500 kPa) is needed. Because this is a
dead headed system, a pressure relief set at 84 psi (580 kPa) must be included in the fuel line between the tank pump and the
engine mounted high pressure pump.
Part number 22966044 is one example of a compatible pump and it includes an integral pressure relief system.
A pump with excessive capacity may result in cavitation at low flow due to the pump repeatedly stopping and starting instead of
controlling to a speed/pressure. Alternatively, a fuel system operating at a fixed 72 psi (500 kPa) could be used and a fuel pump
relay may be triggered by the Green/Gray wire in cavity 2 of the Fuel Pump Power Module

so looks like you still need the fuel pump control module. If you use only a ignition power to relay and control the fuel pump, then the fuel pressure sensor will be useless as that sensor is how the ECU controls fuel PSI.
will it work.. sure, will you get drivability problems.. likely

Just updating my post, since I cannot edit it.

[vannatta20]

Going on my experience ( 6 gen v swaps) they all used 57 psi fuel pressure with no issues. Fuel trims are dead on and wot is fine. If this will not work I should have experienced some issues. By all means use a fpcm I just have not had the need as of yet. I was surprised since GM says 72 psi needs to be used. So far no issues at 57 psi. There are many different ways to do this I am just letting people know what is working so far.

[djhenderlong]

I'm currently working on a Turbo 2016 L83 / Powerglide swap and I have a few wiring questions.

1. Is the BCM required if I am not running a stock trans? I believe the answer is no. If that is the case - do I need to loop any data lines in order to trick the ecu that there is a BCM connected?

2. Does anyone have a accelerator pedal pinout? I bought the truck pedal, however the pins are not labeled on the physical pedal (a, b, c, ect).

3. In order to use HP tuners, I need an OBD2 connector. I bought a small connector but I do not see how this is wired into the harness. Does anyone have this pinout?

4. Because I am not running the stock trans, am I correct by saying that I would need to flash the ecu as a manual trans? I have also been hearing that I need to add a jumper wire to the trans output on the harness side. This jumper allows the data lines to be connected to one another. Does anyone have a pinout/diagram of this?

Thanks for all the help,
Dave.

[thefishpimp]

I read these blogs quite a bit, but never post. So here goes nothing...
I'm putting a 2015 L86 and 8l90 into a 1971 K10 Suburban currently. Truck is currently stock height but may in the future get a lift. I have the motor and tranny hooked up to a NP241c passenger drop with electronic VSS and will be mounting it up into the truck soon. Don't know who I'll have do the harness yet, but I've looked at Speartech and I'm currently talking with Motech as I'd like to retain AFM (DOD). I'd like to have touch shifting, towing mode, AC, Power steering and probably more but haven't worked all that out yet. I'll be glad to add info as I go along.

[vannatta20]

You might have talked to me. I work at Motech and I am the gen v guy to talk to. We now have a muscle car module that gives tap shift and ac serial on command with out a bcm. We also have cruise working now.

[Clyde65]

I am working on a 64 crewcab with l83/6l80 going in..

[Daaaanz67]

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[Hart_Rod]

Originally Posted by daaaanz67

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+1

[Evldoer]

Originally Posted by vannatta20

You might have talked to me. I work at Motech and I am the gen v guy to talk to. We now have a muscle car module that gives tap shift and ac serial on command with out a bcm. We also have cruise working now.

I checked Motechs website and didnt see anything about your musclecar module. Im ready for one. Or 2. Engine is in the truck and im working on the wiring now. I would like more details on your module because i want tap shift, cruise, etc. This is in a 78 c10 2wd. I will also be doing an l83/6l80 into an 85 k10 immediately after i get the details worked out with the first truck. Also have the power steering problem figured out

[mcmlxix]

I need a GEN V .. who's giving them away?

[Clyde65]

Originally Posted by Evldoer

I checked Motechs website and didnt see anything about your musclecar module. Im ready for one. Or 2. Engine is in the truck and im working on the wiring now. I would like more details on your module because i want tap shift, cruise, etc. This is in a 78 c10 2wd. I will also be doing an l83/6l80 into an 85 k10 immediately after i get the details worked out with the first truck. Also have the power steering problem figured out

So what did you do with the ps issue? How about the vac pump??

[Evldoer]

I used a type II pump, removed the vac pump. Machined up an aluminum bracket that mounts to the 4 holes that the vac pump used.
Im going to delete the DOD/AFM so hopefully the engine will make enough vacuum to operate the power brakes. If not i will just add an electric vacuum pump.
I didnt like any of the aftermarket offerings to mount a power steering pump, and felt this might be a better solution.

[Clyde65]

I was thinking of going with hydro brakes. Thoughts??

[Evldoer]

That is a good option as well. I know for sure that the dodge trucks with cummins use the type 2 power steering pumps, and have hydroboost. If you buy a pump from the dodge dealer (for a 2003)it comes with the resevoir so thats a step in the right direction. Then you just need to figure out the plumbing.

[Clyde65]

What is a type II pump?

[Evldoer]

Type II, or 2, pump is the saginaw pump without the integrated resevoir. The old style used on c10 trucks and newer ls powered trucks use the pump with the reservoir around the pump. This is the P series pump.

Type 2 pump is what the ls powered cars use. As well as alot of othe vehicles. This has a remote resevoir sometimes connected with a hose for the supply or just a nipple on the tank that is pressed into the pump.

[Clyde65]

Gotcha! Thanks for that info!!

[Marine15Z28]

Originally Posted by Evldoer

I used a type II pump, removed the vac pump. Machined up an aluminum bracket that mounts to the 4 holes that the vac pump used.
Im going to delete the DOD/AFM so hopefully the engine will make enough vacuum to operate the power brakes. If not i will just add an electric vacuum pump.
I didnt like any of the aftermarket offerings to mount a power steering pump, and felt this might be a better solution.

Are you going to sell those brackets for the power steering pump, I'm interested in 1 or 2, DM me please, Thanks

[Clyde65]

What have y’all used to connect to the fuel rail??