Performance 4L60E build thread
AFL balance hole, .052"
The top arrow is the servo release/3-4 hole, Bottom arrow is AFL balance.
I have 2nd drilled to .093, 3rd and 4th drilled to .108, using a 4l70e servo with. 060" travel. 7 disc BW high energy 3/4 clutch @ .030 , .490 boost valve, and a stock torque converter. Does this sound reasonable?
I didn't do mine to save money (In fact I could have saved a ton having mine built), I did it for fun, and to prove to myself that I could. Well I did, and the first time around it had a bad 2-3 flare, so out it came again for more learning(the hard way), fortunately nothing was smoked. bang:
Mine also isn't going behind an expensive high horse engine. I don't want to discourage you, but If I were in your shoes I would think about having a good one built.
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The only thing "ultimate" about PATC is their ability to over-promise and under-deliver. They haven't invented anything; just using readily available parts.
The new close-ratio planetary gears are now available from Sonnax for about $600 (IIRC). I have the original billet gear set that cost much more.
And what else would you recomend for this build? I have built several 4L60's and have about 75% success rate out of 20 or so. I'm just an amature at this shi. Stuff
https://ls1tech.com/forums/automatic...s-4l60e-2.html
I tried Blue clutches and they wore out in 1 year with 3000 miles of spirited driving. So go with BW HiEnergy. I personally have used the Raybestos GPZ in my current and several other 4L60E that I drove/raced. They seem to be equivalent to the BW HE, but most of the pros/sponsors here use the BW HE.
Add the best BW forward sprag. Add the Sonnax HD 2-3 shift valve; this will keep the overrun clutches engaged in D3 and with this valve (and only with this valve) you should race in D3. (Without the valve, race in OD.)
Why not get a better converter? Even a 3000 stall works great with a stock engine and with any significant cam upgrade you may want a 3600.
What is your rear end ratio?
The only thing "ultimate" about PATC is their ability to over-promise and under-deliver. They haven't invented anything; just using readily available parts.
The new close-ratio planetary gears are now available from Sonnax for about $600 (IIRC). I have the original billet gear set that cost much more.
I did talk to PACT prob 5 years ago, he wouldn't sell or make me a parts list for a 60 that will handle 500hp turbo car. he figured I was either young or it was my first time and tried selling me and 80e. no he builds and offers full kits for 60e.
https://ls1tech.com/forums/automatic...s-4l60e-2.html
I tried Blue clutches and they wore out in 1 year with 3000 miles of spirited driving. So go with BW HiEnergy. I personally have used the Raybestos GPZ in my current and several other 4L60E that I drove/raced. They seem to be equivalent to the BW HE, but most of the pros/sponsors here use the BW HE.
Add the best BW forward sprag. Add the Sonnax HD 2-3 shift valve; this will keep the overrun clutches engaged in D3 and with this valve (and only with this valve) you should race in D3. (Without the valve, race in OD.)
Why not get a better converter? Even a 3000 stall works great with a stock engine and with any significant cam upgrade you may want a 3600.
What is your rear end ratio?
this converter was $99, I'm $1200 into this thing already, with all of the new hard parts i'm getting. sheesh they are expensive to repair and upgrade, "correctly" that is
Last edited by Tinbender59; Oct 27, 2015 at 09:03 PM.
Their purpose was to reduce wear on the 3/4 clutch when the trans is in 1st and 2nd gear, which is rarely. As mechanics complained that the 3/4 clutch was wearing out due to slippage, many started to remove the springs as that increases the clamping pressure on the clutch by about 8 lbs. Since clamping pressure at full stock line pressure is around 700 lbs, that isn't a big difference.
Therefore, I personally keep the springs in, especially in a performance build with higher line pressure (800 lbs of clamping), drilled separator plate for faster clutch engagement (and less slipping) and tighter clutch clearance.
In short, the springs reduce the clamping force by about 1%, but might reduce the wear on the clutches if you drive a lot in 1st and 2nd gear.








