Converter Slippage at top end

[Dan Fahey]

Currently using a 10 inch Yank 4400PT Locking converter.
Calculated a 12% slip based on Wallace Racing Calculator

What is a typical converter slippage on Racing Converters.

Trying to determine best gear ration for my 95 Impala SS for Stock

Dan

[Jim Hanig]

Originally Posted by Dan Fahey

Currently using a 10 inch Yank 4400PT Locking converter.
Calculated a 12% slip based on Wallace Racing Calculator

What is a typical converter slippage on Racing Converters.

Trying to determine best gear ration for my 95 Impala SS for Stock

Dan

should be 4 to 7%

[Jeff Stout]

Going through this right now. I was at 13% and tested using John Deere Hydraulic oil and dropped 300 RPM. I think I'm at 9% now. It was just an experiment and now will remove converter to tighten up top end and hopefully keep starting line rpm the same. Debating on what to get converter set at because I race from 2000ft to 6500ft of air throughout the year and don't want to change converters.

[Tom Goldman]

The PT converter is a lockup so you should have ZERO slippage .
If you are using it as a non lock up of course your slippage will be higher than a real purpose built Stock Eliminator converter .

[Dan Fahey]

Originally Posted by Tom Goldman

The PT converter is a lockup so you should have ZERO slippage .
If you are using it as a non lock up of course your slippage will be higher than a real purpose built Stock Eliminator converter .

Have not used the lock up !!

YET !!

Dan

[Dan Fahey]

Originally Posted by Jeff Stout

Going through this right now. I was at 13% and tested using John Deere Hydraulic oil and dropped 300 RPM. I think I'm at 9% now. It was just an experiment and now will remove converter to tighten up top end and hopefully keep starting line rpm the same. Debating on what to get converter set at because I race from 2000ft to 6500ft of air throughout the year and don't want to change converters.

This is interesting

I use Amsoil for racing

[Mark Yacavone]

Originally Posted by Dan Fahey

Currently using a 10 inch Yank 4400PT Locking converter.
Calculated a 12% slip based on Wallace Racing Calculator


Dan

Not sure why you included this info, but if you're going to use a T200 and an 8" converter, there are plenty of people here who can figure what gear you'll need. You won't have to figure a thing.
Only question would be: Will you have enough steam to run a second under, or are you just looking to run the index?

[ss3011]

Originally Posted by Mark Yacavone

Not sure why you included this info, but if you're going to use a T200 and an 8" converter, there are plenty of people here who can figure what gear you'll need. You won't have to figure a thing.
Only question would be: Will you have enough steam to run a second under, or are you just looking to run the index?

Hopefully Mark will back me up on this , since he has a lot of converter experience . A 10" converter is an odd choice in stock . Example , To make a big converter stall up at 5000 rpm will trade efficiency and make it slip a high percentage through the traps It is much better to have a 8" converter configured to stall at 5000 rpm , and gain back the overall efficiency through the traps . A bonus of the smaller converter is the coupling point of the converter (the point that converter multiplication goes to 1 ) will be at a higher rpm . A big converter will get to 1 to 1 at a lower rpm , so the car will not accelerate as quickly while the converter gets through this in-efficient part of the converter curve .

[Dan Fahey]

Originally Posted by Mark Yacavone

Not sure why you included this info, but if you're going to use a T200 and an 8" converter, there are plenty of people here who can figure what gear you'll need. You won't have to figure a thing.
Only question would be: Will you have enough steam to run a second under, or are you just looking to run the index?

Staying with 4L60E..
If it breaks PerformaBuilt will rebuild.
Far less expensive than a built Th200-r4 and much stronger.
Don’t have to make a new Cross member or Size a new drive shaft.
More first gear for weight of car
8 inch Converter is being built.

[Mark Yacavone]

Originally Posted by Dan Fahey

Staying with 4L60E..
If it breaks PerformaBuilt will rebuild.
Far less expensive than a built Th200-r4 and much stronger.
Don’t have to make a new Cross member or Size a new drive shaft.
More first gear for weight of car
8 inch Converter is being built.

So you're using an o/d - lock up trans, but not using either ?
Gearing it tight in 3rd for a big duration Stocker cam?
Oh.