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Discussion Starter #1
Knowing this is a complicated question, I am looking for a simplified recommendation based on info below and others experience. I know how they work, just not what stall speed is best for my car/needs.

1966 gto
68 400 (.030 over)
#16 heads
mild cam (do not know specs), headers, 750 holley DP
Th400
3.25 rear

I do not race. Looking for best street performance without too hard of a brake stomp at red lights or in traffic. i lost my paperwork, so not sure what is currently in there, but it does not seem efficient and like I'm not seeing all the torque the engine is producing.

Thanks!
 

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Yes good advice....talk to Coan Racing in Kokomo Indiana...they build torque converters...

or Performance Torque Converters PTC in Muscle Shoals, Alabama they build them too...

Mr. Coan still there invented the trans brake in the 70’s.....they have a plant there pretty impressive place.....about 30 employees building Torque converters....

Both are very good there are many other brands.....
 

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1967 400/400
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Knowing this is a complicated question, I am looking for a simplified recommendation based on info below and others experience. I know how they work, just not what stall speed is best for my car/needs.

1966 gto
68 400 (.030 over)
#16 heads
mild cam (do not know specs), headers, 750 holley DP
Th400
3.25 rear

I do not race. Looking for best street performance without too hard of a brake stomp at red lights or in traffic. i lost my paperwork, so not sure what is currently in there, but it does not seem efficient and like I'm not seeing all the torque the engine is producing.

Thanks!
I've been going through the same thing for the last three weeks, with similar engine specs on my 67. I've spoken to the big manufacturers, cam designer, and engine builder, and it's all over the board. Most recommended 2800 and up. The forum guys tended to lean around the 2500 mark and so I'm shooting for the 24-25 range.

I was also told by two manufacturers that the budget TC's (which they all sell) are rated to a max of 450HP, and that due to the healthy torq characteristics of a Pontiac engine, the budget models should not be used. So... that puts the TC's into the $600 range. This has been my life for the last week. Be prepared.
 

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Discussion Starter #5
Thanks, 2800 seems so high to me for a stock driver...I've been getting told 2400-2600 though, so guess its close.

Where do PDQ converters sit on the scale of budget to "good" converters?

I'm considering buying a locally rebuilt '68 TH400 with Transgo 2 shift kit, heavy duty thrust washers and a 32 sprag with a PDQ 2500 stall converter. I suppose it would be a good fit for my driveline and driving, but...
Any opinions on what a good price would be for a tranny like this?
 

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1967 400/400
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Thanks, 2800 seems so high to me for a stock driver...I've been getting told 2400-2600 though, so guess its close.

Where do PDQ converters sit on the scale of budget to "good" converters?

I'm considering buying a locally rebuilt '68 TH400 with Transgo 2 shift kit, heavy duty thrust washers and a 32 sprag with a PDQ 2500 stall converter. I suppose it would be a good fit for my driveline and driving, but...
Any opinions on what a good price would be for a tranny like this?
Agree. There's just no good answer. Every time I think I have it nailed down, I talk to another expert and they debunk whatever the privious expert said. And these are all of the emanufacturers, mostly presenting new obstacles This is why the new information source is tainted. I've personally spoken to at least 4, reputable/ recommended manufacturers and they all told me that a Pontiac with a mild cam requires a converter above the budget line. So... $600 and up.

But like LG says, the trans issue is a local thing. If shipping were an option, I'd sell you mine.
 

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Discussion Starter #9
Agree. There's just no good answer. Every time I think I have it nailed down, I talk to another expert and they debunk whatever the privious expert said. And these are all of the emanufacturers, mostly presenting new obstacles This is why the new information source is tainted. I've personally spoken to at least 4, reputable/ recommended manufacturers and they all told me that a Pontiac with a mild cam requires a converter above the budget line. So... $600 and up.

But like LG says, the trans issue is a local thing. If shipping were an option, I'd sell you mine.
Man, it is frustrating not getting a square answer.

not sure what to do...
My current TH400 is giving me fits. Not kicking down, shortshifting really bad, sometimes flares 1-2 on manual shifts, won't blip tires under hard 1-2 shifts anymore.
The car sat for about 3 years with infrequent start ups every 4 months, but otherwise the only thing that has changed since it was working properly is the vacuum source to the modulator (new carb) and a new filter and fluid change.

Contemplating doing a 200r4 swap, but no fundage for that now. A lame auto tranny really ruins the fun of the car.
 

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Discussion Starter #10
Yes good advice....talk to Coan Racing in Kokomo Indiana...they build torque converters...

or Performance Torque Converters PTC in Muscle Shoals, Alabama they build them too...

Mr. Coan still there invented the trans brake in the 70’s.....they have a plant there pretty impressive place.....about 30 employees building Torque converters....

Both are very good there are many other brands.....

Question, is there a "field procedure" to determine the existing stall speed of the converter (in the car) without dropping the dust shield and searching for a part number or something?
I've read that stomping the brakes and revving in first until the brakes are overpowered (while watching the tach) can get you this info, but is that true and/or accurate?

I did the tranny a long time ago and cannot find the paperwork.
 

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1967 400/400
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Man, it is frustrating not getting a square answer.

not sure what to do...
My current TH400 is giving me fits. Not kicking down, shortshifting really bad, sometimes flares 1-2 on manual shifts, won't blip tires under hard 1-2 shifts anymore.
The car sat for about 3 years with infrequent start ups every 4 months, but otherwise the only thing that has changed since it was working properly is the vacuum source to the modulator (new carb) and a new filter and fluid change.

Contemplating doing a 200r4 swap, but no fundage for that now. A lame auto tranny really ruins the fun of the car.
I'm far from a trans expert, but it sounds like your pump pressure might be down. I too have been trying to "test" my TC, but it seems like... nope. Find an AAmco and and bring it there? Half of them are crooks. The joys of old cars. This is why I'll wind up doing a TKO swap.
 

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Discussion Starter #12
I hear that. If I had the $ I'd do a TKO as well, but I want my wife to be able to drive the car..she likes it and that's a good thing. So I see a 2004R in my future. This Th400 is driving me nuts and killing the performance of the car. Plus, I just bought a new rear with 3.25 so an extra OD gear would help at speed.

That said, my dad put a 5 speed super T-10 in his '69 cougar and it totally transformed the car into a menace. The tired C4 absolutely neutered the Ford Racing 302 we put in. Now it is a beast off the line and rolls at 80 at 2100 RPM. Pretty amazing
 

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I hear that. If I had the $ I'd do a TKO as well, but I want my wife to be able to drive the car..she likes it and that's a good thing. So I see a 2004R in my future. This Th400 is driving me nuts and killing the performance of the car. Plus, I just bought a new rear with 3.25 so an extra OD gear would help at speed.

That said, my dad put a 5 speed super T-10 in his '69 cougar and it totally transformed the car into a menace. The tired C4 absolutely neutered the Ford Racing 302 we put in. Now it is a beast off the line and rolls at 80 at 2100 RPM. Pretty amazing
I've never seen a trans repair cost less than $1000... Even if it's a pump, you still have to drop it all. Don't know where you're located, but my freshly rebuilt, OEM TH400 will going for sale soon.
 
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