Who has had good luck with the stock 4L80E + Transgo shift kit combo? I plan to run the mid-level Circle D converter, and a Trucool cooler.

 

You will have great luck with that combo. My only advice is adding a sonnax boost valve rather than using the HD2 pressure release system.

 

I'm running the 4L80E with the HD-2 kit and PTC Multi-disk. It's done well behind the BBC so far. No complaints at all..

 

Great! Tonight I picked up a low mile 4L80e that was behind an 8.1L

Does anyone know if the 8.1L internals/ gear ratios are the same as the 6.0 trans? I'll be purchasing a Circle D converter soon.

 

another stock 80E with transgo here. so far so good behind my heavy truck with a 4000 stall

 

Another 4l80e HD2 here with no problems. As said above the sonnax boost valve is a good idea (I installed the relief valve from the kit before I knew better but still no problems).

 

same here aswell.... i put the valve in that came with the hd2 kit before i knew about the sonnax but ive beat the crap out of this 80e behind my nitrous big block and now my turbo 4.8 and no issues with any trans internals as of yet.

 

Thanks guys! Bought a low mile 4L80e out of a 2004 Suburban 8.1L last night. Paid $500 for it and I'm stoked! What's all this about the Sonnax valve? Seems like there are an awful lot of guys indeed running the Transgo kit as-is.

 

its just a better way then the transgo boost valve plus you don't need to drill your valve body that plate setup is a POS imo

I'm running a HD-2 I'm my stock 80E with a sonnax self regulating boost valve so far I'm happy with it

 

What part# are you guys buying for the sonnax valve for our 80e trans? Ive got another 80 im getting built and may aswell put one in this next one along with hd2...