(I realize this might be a drivetrain topic, but this question is more specific to blown applications, hence the post here).

I recently roasted the 3-4 clutchpack in my 4L60E on my first post-breakin decent test drive with the new 396LT4 w/8psi of boost.

The 4L60E rebuilder market is full of high-dollar units with cryogenic output shafts and stuff that I don't think solves the basic problems of the transmissions, at least in blown applications.

I'd like to hear input on what, specifically, people with high power blown motors have broken in 4L60E transmissions and what upgrades have been useful.

Thanks!

 

The Transmission ... Full rebuild, HD sprag, Delco bearings, Clevite bushings, Borgwarner Frictions. The forward clutch has the stock number of frictions, just the Borgwarner frictions. The 2nd apply servo is the Superior "Super Hold" #7012. The 3rd clutch has 1 more friction than stock, 6 Borgwarner frictions. There is an SK mild shift kit in it. The 3rd clutch release springs are the heavy duty springs that came from a Trans-go shift kit. The boost valve is .500, from the Trans-go shift kit. ......

The result ... no need for the HPP+ set to "firm shifts". The shifts are quite a bit firmer than stock. The 1 - 2 shift is firm and good. The 2 - 3 shift is harsh and even somewhat objectionable untill the revs get up to 3,500 at 1/2 throttle or better, then it smooths out and is good. The 3 - 4 shift is good. The T/C lock up is a bit on harsh side, quite noticeable if you tap the brakes at 60mph, which will cause it to unlock and then relock. The unlocking of the T/C under increasing throttle is a bit delayed, but when it unlocks, it is good. The 4 - 3 downshift is good, the 3 - 2 downshift is firm and good, not an inkling of slippage. The 2 - 1 downshift ... just boils the tires anyway ...

I also boosted every transmission table I was able to find in the LT1 editor. Nothing major, just a 15 - 30% gradual increase in apply pressures and the like. Anywhere it looked like the increase torque might cause slipping in the low to mid range was "beefed".

Now at 550rwhp and holding ... but do note that I am running street tires, and they are what slips in the first place ... I kinda like it like that.

Hope this helps

LWM

 

Call East Side, they build a great tranny. Not sure on all the tech stuff, but i know they work and work well for any application.

 

What the hell do you know....you drive a stick

Jackass

Uncle Marc

 

If you are on the East Coast, try http://www.dynotechperformance.com/

They can build a 4l60E to handle upto 650FWHP.

Here are some of the components they use "All new clutches, bushings, paper and rubber seals. Includes Transgo shift kit, 13-vane blueprinted pump assembly, Raybestos Pro-Series band or Alto wide-band, Raybestos Blue or Alto Red Devil 3-4 clutches, Modified lock-up controls. All new electronics. Teflon pump/drum and tail housing bushings. Billet 1-2 apply servo, billet 4th gear apply servo. Beast Heavy Duty sun shell assembly. 3-4 servo release check-valve"

Eric, the guy who builds em told me they have a Vette with a 4l60E in the 9s and has been running so for a whiles now. I had them build my trans as well, unfortunately I am having some issues with my motor so I really did not get to beat up on it as much but so far, so good.

They also have an Article in the latest GM-Hightech Article about their stout TH2004R. They are located in Mannville NJ.

Hope this helps,
Claude

 

hey hey easy. A couple friends did the ESP st5 tranny, they work out very well.
sory for speeking man, wait till the next time i see you at the track. Im going to trip you!