Torque Converter selection

Packfan

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I know there are a lot of threads on torque converters but I am looking for some advice. I am getting ready to put the 440 and the 727 back in the '67 GTX and I know nothing about converters. The car has a Sure Grip diff but the gear ratio tag is no longer on it. I see there are several different sizes 9", 10", 11" available. Just looking for something stock with stock stall. Anyone have a brand and part number to order? Thanks!
 

furyus

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Your best answer would be to call different converter companies for their recommendation. One thing that they will ask, is what gear ratio. So, you need to know that. There's videos on YouTube that can show how to find out.
Basically, mark the tire, and the driveshaft. Rotate the rear tire one turn, while counting driveshaft turns. If the driveshaft turns a little over 3 turns, it's probably a 3.23. 3 1/2 turns, and it's a 3.55.
 

PRHeads

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A local trans rebuilder should have access to a remaned stock unit.

A factory stock converter for a 67 440 should be a 12”.
 

Packfan

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Looks like I have the 3.23 gears. Not quite 3 1/4 turns of the yoke to one rotation of the tire.

........... The fella who rebuilt my 727 suggested I purchase a new converter while going through all the work of rebuilding the trans. The one I had was working fine. There is a 2709 and a 1096 stamped into it but not sure if that has any value to identifying it. Reuse it?

20220313_170028[1].jpg
 

toolmanmike

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I know there are a lot of threads on torque converters but I am looking for some advice. I am getting ready to put the 440 and the 727 back in the '67 GTX and I know nothing about converters. The car has a Sure Grip diff but the gear ratio tag is no longer on it. I see there are several different sizes 9", 10", 11" available. Just looking for something stock with stock stall. Anyone have a brand and part number to order? Thanks!
https://gopnh.com/ Precision will have what you need. Tell them you need one like Joe Scholbrock got.
 

493 Mike

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Looks like I have the 3.23 gears. Not quite 3 1/4 turns of the yoke to one rotation of the tire.

.............. The fella who rebuilt my 727 suggested I purchase a new converter while going through all the work of rebuilding the trans. The one I had was working fine. There is a 2709 and a 1096 stamped into it but not sure if that has any value to identifying it. Reuse it?

View attachment 1254634
If the trans was not burned up before rebuilding and fluid was decent looking I recommend reuse. I've done it dozens of times in my rebuilds. A Torque Flite will operate with lots of dirt (not that it's desirable) compared to a Ford or GM tranny.
Mike
 

dvw

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No problem reusing the used factory 12" if if you liked the performance. A high stall 11" factory converter would wake it up.
Doug
 

Dave6T4

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Chrysler put 11" higher stall torque converters in Hemi and 383 Magnum engines to help with relatively weaker low rpm. torque. The 440 Magnum engines still received the lower stall 12" converters, with Chrysler figuring these motors had enough low end torque that they did not need the help. I built my 1967 R/T so long ago that I could still buy the 11" Hemi converter through NAPA, etc., so that is what I have.
 

Ray70Chrg

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Hello Packfan, As you found out, that converter is a Summit tc. part # SUM-G2709. If you read the reviews you know that they were unfavorable to this TC. Yours maybe working ok but not performing at a very high level. I suspect that mine is also in that category although I don't know anything about it except that it's painted blue and I'm not satisfied with the low end performance of my 383. Yes many other factors are at play and I've addressed several of them. If your engine builder suggested to change the TC, than ask why. I've been trying to gain some knowledge about TCs in general and have decided that if a converter IS what I need then I've made up my mind a get a Hughes performance 24-25 unit. Not recommending that you do anything at all, just saying where I'm at on this topic. Good Luck
 
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Packfan

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Thanks for the great feedback fellas. I agree with you Ray, the feedback is not good on my Summit TC and I only drove the car a mile after buying it because the engine would not run worth a dang (was a 383). I am going to call Precision tomorrow and see what they think. Man, the price on these things!
 

GTX JOHN

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Looks like I have the 3.23 gears. Not quite 3 1/4 turns of the yoke to one rotation of the tire.

.................The fella who rebuilt my 727 suggested I purchase a new converter while going through all the work of rebuilding the trans. The one I had was working fine. There is a 2709 and a 1096 stamped into it but not sure if that has any value to identifying it. Reuse it?

View attachment 1254634
Stick a screwdriver in it and check one way clutch to make sure it is not
broke and goes backwards. Flush it out and make sure nothing is in pieces
with a strainer. 99 times out of 100 it will be fine. I have not seen a NOS
stock convertor in 40 years = All my converters are built out of used cores
that we replace the internals.
The 10 3/4 converter would make a huge difference over the 11 3/4.
Look for one that has a smooth cover (340 original) and it will stall 300
higher that one with a flat area on to (383/Hemi).
Count the splines as they changed the count in the 67 model year up to 24.
Early one will not fit front pump.
The converter in picture appears to be 11 3/4.
Almost every big town out out here has a converter
rebuilder. Should cost $100. to 150. at most to go thru.
 
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Ray70Chrg

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Stick a screwdriver in it and check one way clutch to make sure it is not
broke and goes backwards. Flush it out and make sure nothing is in pieces
with a strainer. 99 times out of 100 it will be fine. I have not seen a NOS
stock convertor in 40 years = All my converters are built out of used cores
that we replace the internals.
The 10 3/4 converter would make a huge difference over the 11 3/4.
Look for one that has a smooth cover (340 original) and it will stall 300
higher that one with a flat area on to (383/Hemi).
Count the splines as they changed the count in the 67 model year up to 24.
Early one will not fit front pump.
The converter in picture appears to be 11 3/4.
Almost every big town out out here has a converter
rebuilder. Should cost $100. to 150. at most to go thru.
GTX John, When a manufacturer says a TC is 11" does that mean it's actually 10 3/4 ? They never seem to indicate 3/4 inch dimensions. Thanks
 

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