Converter Trouble

Old 09-27-2008, 11:17 PM
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jrthone
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Default Converter Trouble

Can someone explain about the differance in converter sizes. Im running a 632 Methanol injected big block 15-1 C/R and powerglide in a 2900lbs car. 4.86 end ratio. peak torque arond 5000rpm(950ftlbs) What stall and size should i run and whats the differance in converter sizes Eg 8, 9, 10"

Thanks
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Old 09-29-2008, 10:42 PM
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jmarksdragster
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The larger the converter, the lower the stall range, smaller goes higher. Stall is dependent on a variety of things changed in the converter as well as the torque put to it. Too small with too much torque will stall too high. Too large with not enough torque may be made to stall enough but will not be efficient. I would say a 9" with 5200 to 5500 stall(on the transbrake) would work for yours. It would be tough to get an 8" to stall low enough.
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Old 10-08-2008, 02:04 PM
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tweekd
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Just to add, the 8 inch converter will bring a small block or small big block under 850 HP to a high stall that it requires. If you put more than 850 HP to an 8 inch your just going to drive though it. The 9 inch converter is useful to a big block running 900 Hp to about 1350 HP. Anything after that is the territory of a 10 inch or 10.5.

In other words, the bigger the diameter the hungry it will be for power to get it moving.
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Old 10-08-2008, 02:10 PM
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hammertime
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Originally Posted by tweekd
. If you put more than 850 HP to an 8 inch your just going to drive though it.
.
Not true at all, look at all the B&M 8" Converters everyone runs in dragsters with over well over 1000hp
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Old 10-15-2008, 11:46 AM
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Apples VS Oranges here, If you have a light car you can run a smaller dia. converter and get away with it, such as David said, but with a heavy car the torque will blow right thru a small converter.
I did some testing yrs. ago. I had a 9" Hughes converter stalled at 5500 rpm car ran 10.31 @129.85 weighing 3100lbs with a 406" motor. Probably not more than 500 ft lbs torque. A friend had a 2400lb willys and a 8" converter also Hughes 6,000 stall. I put that converter in my car and it slowed down to 118 MPH and went up to 10.85 ET absolutely no other changes all due to the weight of the car. So the weight factor and the torque played all the difference in the world. I can say that most converter builders will not sell you a converter smaller than 10" for a blown alcohol door car and stand behind it. I know that Kenny Ford that owns PTC won't and i've known him for yrs. and only use his converters, and Bill Taylor from BTE won't either.

JMO

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Old 10-22-2008, 03:27 PM
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onedragracer
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Originally Posted by zipper06
Apples VS Oranges here, If you have a light car you can run a smaller dia. converter and get away with it, such as David said, but with a heavy car the torque will blow right thru a small converter.
I did some testing yrs. ago. I had a 9" Hughes converter stalled at 5500 rpm car ran 10.31 @129.85 weighing 3100lbs with a 406" motor. Probably not more than 500 ft lbs torque. A friend had a 2400lb willys and a 8" converter also Hughes 6,000 stall. I put that converter in my car and it slowed down to 118 MPH and went up to 10.85 ET absolutely no other changes all due to the weight of the car. So the weight factor and the torque played all the difference in the world. I can say that most converter builders will not sell you a converter smaller than 10" for a blown alcohol door car and stand behind it. I know that Kenny Ford that owns PTC won't and i've known him for yrs. and only use his converters,

and Bill Taylor from BTE won't either.


JMO

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Dead on the money Zip. Been there done that :!:
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Old 10-22-2008, 07:20 PM
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bjuice
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Originally Posted by zipper06
Apples VS Oranges here, If you have a light car you can run a smaller dia. converter and get away with it, such as David said, but with a heavy car the torque will blow right thru a small converter.
I did some testing yrs. ago. I had a 9" Hughes converter stalled at 5500 rpm car ran 10.31 @129.85 weighing 3100lbs with a 406" motor. Probably not more than 500 ft lbs torque. A friend had a 2400lb willys and a 8" converter also Hughes 6,000 stall. I put that converter in my car and it slowed down to 118 MPH and went up to 10.85 ET absolutely no other changes all due to the weight of the car. So the weight factor and the torque played all the difference in the world. I can say that most converter builders will not sell you a converter smaller than 10" for a blown alcohol door car and stand behind it. I know that Kenny Ford that owns PTC won't and i've known him for yrs. and only use his converters, and Bill Taylor from BTE won't either.

JMO

Zip.
i agree ! on top of that they will build them tighter than Dicks hatband.
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Old 01-12-2009, 11:59 AM
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desoto30
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Originally Posted by tweekd
Just to add, the 8 inch converter will bring a small block or small big block under 850 HP to a high stall that it requires. If you put more than 850 HP to an 8 inch your just going to drive though it. The 9 inch converter is useful to a big block running 900 Hp to about 1350 HP. Anything after that is the territory of a 10 inch or 10.5.

In other words, the bigger the diameter the hungry it will be for power to get it moving.
How do you tell & know when you are "driving through" the convertor?
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Old 01-12-2009, 07:54 PM
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jed5161
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if its already in the car and already running it....if its a "too loose" converter...you'll notice you cant tell much of an rpm drop at shift. would sound the same as if you short shifted. Would also get alot of heat and eventually kill the converter.
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Old 01-13-2009, 03:27 AM
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shawnp
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I have a Hughes convertor listed in the classifieds that might work but you would want to check with them. Your other option would be to call Marco who is becoming the hottest thing in convertors, http://www.abruzziracing.com/
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