4L80 questions

[Ribbedroof]

So I'm considering buying another G body that is claimed to have a manual only valve body . It's a cruiser, not a track car, and would be a cruiser If I were to buy.

How much is involved in turning this back into an automatic? Valve body obviously, and I'm assuming some sort of controller as well? Car is running a Sniper on a SBC. This would be my first foray into "modern"🤣 tech in a non OEM platform.

Trying to spend more time driving, less time "project"ing...time seems to be like that toilet paper roll...the closer to the end, the faster it goes

 

[SS_Malibu]

Since you’re just about completely rebuilding it to bring it back to a regular driver, you might as well build another one to replace it and if you don’t need the one that’s in there, sell it to recoup some money spent.

 

[Sweet_Johnny]

I'm also new to modern tech but have fried multiple ODs and researched the 4L6** extensively, hoping to drop one into a G Body. It's close enough for conversation. Does it actually have a manual VB or did someone just hook up a $50 eBay controller and call it manual? I've looked into those and even the "good" ones fry the trans in short fashion. Wiring the solenoids to the shifter positions or even SPST switches gives full manual but saves the trans. The torque converter would need the same for lockup functionality. A standalone like a U.S. Shift Quick 4 would solve those issues easily but don't bother with an Aces Quick Draw- lack of correspondence. I've had my eye on a Quick 4 for sale on another forum recently, maybe it's still available:

Brand New US Shift Quick 4 Gen2 Stand-Alone TCU

Brand new US Shift Quick 4 Gen2 Stand-Alone Transmission Control System. This controller works on ALL of these transmissions: GM 4L60E, 4L65E, and 4L70E (2008 and earlier only) GM 4L80E and 4L85E Ford AOD-E, 4R70W (wide ratio AOD-E), and 4R75 Ford E4OD and 4R100 The harness is...

nastyz28.com

On a performance trans if it needs a different VB then I'd be concerned that the pressure settings and various valves & mods inside are necessary for the longevity of the other parts and mods- VBs are extremely complicated. The clearances, separator plate, accumulators, and servos all need to be copacetic with the VB and its many fluid paths, if you change that it might not be happy. Clutch/ band clearances not matching the orifice size in the separator plate could result in dragging clutches or simultaneously engaging two forward gears- this is a game of thousandths, though it takes a few. Same goes for clutch apply pressure, speed, and clutch material. If fluid paths were modified to eliminate an accumulator or redirect fluid to initiate an act in a different way then you're immediately in trouble. I'd hope that a competent specialist could recreate the mods in another VB given that they're conducive to full auto control.

In researching various mods done by reputable performance shops and even a GM hydraulic engineer I discovered that there's about 1k ways to mess one up. I'd hate to kill a good one by mismatching parts.

If it's not a "built" trans then perhaps the VB could be swapped without issue, and a standalone controller or switches will get you rolling. I'd still be leary of swapping VBs as there were various changes to the 4L6** over the years that "don't matter" until they do, like in custom applications. I can't say for sure if the same is true for the '80.

Holley forums turned up this:

https://forums.holley.com/forum/holley-efi/sniper-efi/8014-sniper-efi-electronically-controlled-transmissions/page4#post296076

https://forums.holley.com/forum/holley-efi/sniper-efi/32193-sniper-efi-with-tcm920s-4l80e-transmission-controller

 

[86 Salon]

Is it a 4L80 or a 4L80E? If it's a 4L80, more than likely you can just install an original valve body. If it's a 4L80E, you'll need some sort of controller. If you can get the car at the right price, it can be a good deal, but use the transmission as a bargaining tool. It seems strange that someone would install a manual valve body in a cruiser. There's a good possibility that there's something wrong with the transmission.

 

[olds307 and 403]

As said the valve body will probably need changed, depending on how the manual conversion was done. Probably best to get the Sniper TCM to control it with the same 3.5" handheld. While I have been less than thrilled with the Terminator X Max on my Olds 350 SEFI conversion, the trans control works quite well. I did have to adjust the 3 to 4 shift to happen later under light throttle. Very normal shifts with their tables. I am installing the Transgo 4L80E HD2 shift kit this weekend to add even more durability to this trans.

 

[Ribbedroof]

Looks like a moot point, guy won't respond despite having it listed for sale and having read the messages I sent.

Back to the drawing board I guess

 

[86 Salon]

Looks like a moot point, guy won't respond despite having it listed for sale and having read the messages I sent.

Back to the drawing board I guess

Take that as a good sign. Wait until the right car comes along. They always do.