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Old 07-12-2025, 01:21 PM
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GOAT8U2 GOAT8U2 is offline
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I was in the converter business for about 7 years, an 8" converter could actually be an 8 3/4 turbine ID. Depending on your stator, your power and shifting rpm it's easy for those little guys to slip. A 6500rpm shift is not a great window for them under high power to really couple at peak.

But on a car that shifted at 8500+ and was a 4.42 AWD these would be killer up top even at 800hp.

The 9" could be the 9 1/4" ID turbine and depending again on stator, power and shift rpm you might see a big drop in slippage.

Thick John Deere fluid can easily tighten a couple % or more depending on total slippage.

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  #2  
Old 07-14-2025, 05:08 AM
Dragncar Dragncar is offline
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Quote:
Originally Posted by GOAT8U2 View Post
I was in the converter business for about 7 years, an 8" converter could actually be an 8 3/4 turbine ID. Depending on your stator, your power and shifting rpm it's easy for those little guys to slip. A 6500rpm shift is not a great window for them under high power to really couple at peak.

But on a car that shifted at 8500+ and was a 4.42 AWD these would be killer up top even at 800hp.

The 9" could be the 9 1/4" ID turbine and depending again on stator, power and shift rpm you might see a big drop in slippage.

Thick John Deere fluid can easily tighten a couple % or more depending on total slippage.
Thanks, that was a useful post. I learned something today.
If I can get the slip down to 8% that would be nice.
Got the trans out today. Hopefully the car will be running by Friday.
I bought the 8" years ago from Butler. Kinda makes me wonder about their recommendation.
I pretty much bought the PTC because Langer recommended them. That guy would know who makes a good converter for a Pontiac.
The PTC is a steel stator unit, goes for 1200$ these days.

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