cablebandit

iTrader: (37)

my friend Quicksilverado has a stock 80e that has benn run at 600-700rwhp for 3 years in a 4500+ pound truck...daily driven

jakeshoe

iTrader: (14)

Let's put it this way,
I build transmissions exclusively for performance use. I've been doing it for about 15 yrs as a hobby and at one point full time as my own business. I've seen most of the failures that happen to them and I consider the 4L80E one of the units I'm more knowledgeable on.
The advice is free for those that want to take it, I'm not here to seek business because I have more than I can do now since it's only a part time gig, so take it for what it's worth.

A stock 4L80E will have issues with the 3rd gear clutches at 600 HP. How do I know, because I've rebuilt a couple of dozen that other shops can't get right at these power levels.

Your friend has either done some mods to his trans by way of a valve body kit, elevated the line pressure with tuning or EPC mods, or he's lucky or not putting down the power he thinks he is.

It WILL live at 600 for a little while stock, and he is unlikely to break hard parts like a 4L60 based unit if he does the burnouts correctly, but 3rd gear is weak due to the hydraulics. It's an easy and nearly free modification, and the TransGo Reprogramming kit takes care of it also, but if not done, their time is limited.

blueflamespl

iTrader: (13)

What specifically is the transgo Kit that will eliminate the 3rd Gear slip? I am considering putting a 4L80E in my Camaro and am making 593 FWHP. Thanks

Kurt

eliotmansfield

Indeed.
Actual technical details seem very thin on the ground on this forum - the only advise I ever seem to read is buy a complete tranny from a sponsor.

jakeshoe

iTrader: (14)

The Transgo kit "dual feeds" the direct clutches. This is a mandatory mod on a TH400, 4L80E, TH350, etc for any real HP. Many full manual valve body kits do this, and this is why some less capable builders recommend using a full manual VB for high HP applications on the GM 3 speeds, etc. It's simply because they don't know how to make the trans survive at elevated HP levels and maintain automatic function.

Specifically on a 4L80E, the dual feed is accomplished on the -2 kit by the seperator plate being a 3 piece design. The -3 kit (full manual) it is accomplished by some re-routing of fluid inside and outside the VB. The dual feed is actually accomplished by leaving the 3rd/reverse checkball out of the VB, but this creates a large pressure loss out the reverse circuit. A hole is plugged to prevent this pressure loss, but that causes no reverse circuit. So Transgo re-routes the fluid outside the VB for reverse.

A knowedgeable builder can also accomplish this mod without a VB kit, however the TransGo kit has some other excellent upgrades that make it worth the cost.

As a side note,
Many transmission builders are tight lipped with their tech info. They have earned the right to the info through hard work, research, and trial and error. However much of the info is out there, just not necessarily on this forum.
The policies of forums such as this limit the free distribution of information.

Although I don't do it full time and have no desire to gain any business from this forum ( I don't mess with 4L60Es for performance use) I can't help many people with questions because I can't mention vendors who aren't sponsors. There are many exceptional vendors out there who don't need a paid sponsorship because they have more business than they need through word of mouth.
There are some excellent vendors here and they pay for the right to advertise here, so they have earned that. However it creates a monopoly on not just transmissions but oftentimes the information related to them.

Frost

iTrader: (45)

That's not true; you can tell people about them all you want, you just can't link them.

jakeshoe

iTrader: (14)

Frost,
I appreciate your input. If that's true then it's a good thing.

30th t/a

iTrader: (51)

I wanna add to this thread, the car WILL NOT power jack. thats right, 600rwhp, with the car at a dead stop, brakes on, give it gas.....slowly revs up, and thats about it. However kick it down at 50mph and it lights the tires up. Im wondering if this is related to the strange thing its doing on the dyno?? somehting is not set correctly in the transmission or maybe I dont have something adjusted correct. any ideas?

30th t/a

iTrader: (51)

this is interesting. like I said, the dyno pull would start at 3200 and as soon as it hit about 4200 the rpms shot to rev limiter. It WAS NOT a slow "slipping" rev.