L92 trans options

[Dual quad]

Hey guys, I just picked up an 08 L92 which will go into my 72 swb. The guy that I bought the engine from also had the matching trans, an AWD 6L80e. I didn't buy the trans because I understand that the conversion to 2WD is costly, and I'd have to convert to high hump (which I'd prefer not to).

So, if I don't want to cut my trans hump, I think my next option is a 4L60e. But, I think it has to be a current version with ISS. Also, I'm not sure if would need a trans controller to go along with it.

Any advice or insight?

[BR3W CITY]

The 60e is tsking a big loss in strength. The 4l80e woukd be thr next best bet. Its strong enough, u jist lose the 2 extra gears.

[Dual quad]

Thanks BR3W, but will the 4l80e fit under the low hump?

[BR3W CITY]

My 66 had the smaller trans tunnel option (idk if my low hump is the same size as yours...pause...) I had a 700r4 in there (basically the same size as the 60e. I switched to the 80e and didn't modify the tunnel at all.

[68GMCCustom]

I've got a 4L85e under my short trans hump...but then again I've had vibrations that I haven't resolved...which could require raising the tail of the trans higher then it is...which won't be possible w/o trans hump modification.

[Ford Assassin]

If a TH400 will fit, you shouldn't have any issues with a 4L80e.

[BR3W CITY]

Originally Posted by 68GMCCustom

I've got a 4L85e under my short trans hump...but then again I've had vibrations that I haven't resolved...which could require raising the tail of the trans higher then it is...which won't be possible w/o trans hump modification.

Pinion angle issue?

[solidaxel]

Originally Posted by BR3W CITY

Pinion angle issue?

My thoughts also, work on the rear end +/- difference 2*

[68GMCCustom]

probably.....and yes I need to get the overall angles below 3* for high speed work. The ends have been +/- 0*, 1*, and 2*.....but overall angle is too high tho and why I said I may be changing it.

I want the driveline angle closer to 0 to 1*. I'm up as close to the hump as I can get...thus its coming apart. I've missed racing this year....I won't miss next year!

[BR3W CITY]

Is it a particular rear end setup that is having you run 0-1* on the engine etc? I see most LS's (mine included) installed around 3* down on the engine, and then make up whatever you need to on the rear end.

[68GMCCustom]

With it dropped and the rear now up into the chassis... I'm winding up with a near level (with the ground) driveshaft... yet with more angle on the ends because the trans has 4* down angle yet the rear end isn't much if any below the trans... IS this making any since?

I need the ends to have 0-1* total angle...for little if no movement of the u-joint....at least from what I've read on tuning high speed drive-lines.

[clinebarger]

Originally Posted by Dual quad

Hey guys, I just picked up an 08 L92 which will go into my 72 swb. The guy that I bought the engine from also had the matching trans, an AWD 6L80e. I didn't buy the trans because I understand that the conversion to 2WD is costly, and I'd have to convert to high hump (which I'd prefer not to).

So, if I don't want to cut my trans hump, I think my next option is a 4L60e. But, I think it has to be a current version with ISS. Also, I'm not sure if would need a trans controller to go along with it.

Any advice or insight?

You will need a TCM, A T42 to be exact....Will/can run a 4L60E or 4L80E with the right Tuning & OS(operating system) in both the ECM(E38) & TCM(T42).

If you go the 4L60E route or the 4L65E/4L70E variants, Use an ISS version!

[Dual quad]

Thanks for the feedback guys. I'm thinking that the 4L80e may be my best option as it should be fairly strong in stock trim behind the 6.2.

But, I'm new to the Gen III/IV electronics. I do have the E38 that came with the L92 and it would appear that I also now need a T42. Regarding the tuning and OS, i understand that this should be from a GM model that had those specific options i.e. L92 & 4L80e. Is this something that a tuner would load in?

[68GMCCustom]

you'll need a VIN. Didn't happen to get the VIN of the vehicle it came out of?

[BR3W CITY]

Originally Posted by Dual quad

Thanks for the feedback guys. I'm thinking that the 4L80e may be my best option as it should be fairly strong in stock trim behind the 6.2.

But, I'm new to the Gen III/IV electronics. I do have the E38 that came with the L92 and it would appear that I also now need a T42. Regarding the tuning and OS, i understand that this should be from a GM model that had those specific options i.e. L92 & 4L80e. Is this something that a tuner would load in?

For the most part, yes, but to avoid confusion, random issues and head scratching, its best to come as close as you can. In other words, if you can find a V8/4l80e ECM, then your money. If you can only find a V8/4l60e computer, it will still work, but the tuner will need to do a segment swap to account for the slight differences in the 80e. (the ISS/VSS )
I'm not 100% sure how this gets on in the e38's, but with the Gen III as an example. Getting a v6 computer would have different colored ECM connectors, and ending up with the wrong ones is just a bigger pain. It shouldn't be that terrible to locate one with your combo. Things like DBW/DBC (At least on the gen III) can be taken care of in the tune as well. I know the e38's have the TAC built in as well, so you may even have some more freedom there.

[Dual quad]

Any recommendations for a tuner/programmer?

[BR3W CITY]

Someone in your area with a decent rep, HP Tuners, and a Dyno
Easier said than done right?