Torque Converter problem?
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From: Gulfport FL
Torque Converter problem?
I took my '85 coupe(2.73 rear) on a long run yesterday and ran into a serious problem. When I went over 65 mph my revs were very high(around 4400 rpm) and would not drop unless I let off of the the gas. Normally is runs around 1800 rpm @ 80 mph. Someone told me that my Accel DFI 7 does not control the 700-R4 tranny, but does control the torque converter clutch if the stock ECM is not. Well the shop that installed my Accel DFI took out the stock ECM, so what do you guys think my problem is? Could my torque converter be locking up?
-James
-James
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From: Long Island, NY
I took my '85 coupe(2.73 rear) on a long run yesterday and ran into a serious problem. When I went over 65 mph my revs were very high(around 4400 rpm) and would not drop unless I let off of the the gas. Normally is runs around 1800 rpm @ 80 mph. Someone told me that my Accel DFI 7 does not control the 700-R4 tranny, but does control the torque converter clutch if the stock ECM is not. Well the shop that installed my Accel DFI took out the stock ECM, so what do you guys think my problem is? Could my torque converter be locking up?
-James
-James
Vic
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Your symptoms are typical of a failing (slipping) 3-4 clutch pack. If I am correct, you will soon lose 3rd and 4th gear, and the fluid will have a burt smell. Dropping the pan should reveal a brown slime at the bottom of the pan. 
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From: Gulfport FL
If it is the tranny...can anyone recommend a good replacement...I currently have a Freddie Brown in there(I have recently heard they are crap). I would like to have something that can reliably hold 450hp and 450 ft-lbs of torque. I will rarely take it to the strip, but I want something that will last and also not break my wallet. Do you think I should swap to an 2004r or a 4l60e/4l80e? I rebuilt my stick tranny(T-5) when I was 19 with success, so maybe I should rebuild it...is it even worth it?
-Thanks
-Thanks
Last edited by vette850; Mar 19, 2007 at 08:39 PM. Reason: rebuild?
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From: stop the fun suckers
If you have time and patience - try the rebuild yourself.. plenty of good help here (special mention to Pete K!!!).
Other than that I would recommend a Pete K 700R4 with one of his special Torque converters (2800 stall min). He won't let you down!
BTW: I agree this is classic 3-4 clutch pack symptoms..
Other than that I would recommend a Pete K 700R4 with one of his special Torque converters (2800 stall min). He won't let you down!
BTW: I agree this is classic 3-4 clutch pack symptoms..
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From: Gulfport FL
I do have the time and patience, but what kind of holding power and durability will my tranny have if I follow his recommendations? Also, how much will it cost total between parts and tools? I know that buying a good one from someone else will cost at least $1500 including the shipping and my core shipping
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From: stop the fun suckers
I had every bit of 3k invested in mine before all was said and done.. However, I used all the goodies and a Vigilante Torque Converter (which is almost 1k in itself). However, mine is more re-manufactured than rebuilt in that all the internal parts are new.. virtually nothing was reused sans the case and valve body.
I'm sure Pete K can steer you to whatever it is for your budget! I didnt want to play around because of the stroker and my future plans for it..
I'm sure Pete K can steer you to whatever it is for your budget! I didnt want to play around because of the stroker and my future plans for it..
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Converters with higher stalls build heat. This heat can be offset with a trans cooler. $50 or less buys alot of cooling. They are also easy to install.
If you eliminate the heat, the only concern would be the extra power you make. In street use, very little to worry about. At the strip, slicks and the extra torque puts strain on the driveline. The right converter adds alot of bang for the buck.
We are fortunate. We have lock up converters. At 45 mph(give or take) our converters lock internally. At this time, zero slippage internally = zero heat created. Rpm's drop 2-3 hundred, better milage and durability. It is all good.
If you eliminate the heat, the only concern would be the extra power you make. In street use, very little to worry about. At the strip, slicks and the extra torque puts strain on the driveline. The right converter adds alot of bang for the buck.
We are fortunate. We have lock up converters. At 45 mph(give or take) our converters lock internally. At this time, zero slippage internally = zero heat created. Rpm's drop 2-3 hundred, better milage and durability. It is all good.
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I had every bit of 3k invested in mine before all was said and done.. However, I used all the goodies and a Vigilante Torque Converter (which is almost 1k in itself). However, mine is more re-manufactured than rebuilt in that all the internal parts are new.. virtually nothing was reused sans the case and valve body.
I'm sure Pete K can steer you to whatever it is for your budget! I didnt want to play around because of the stroker and my future plans for it..
I'm sure Pete K can steer you to whatever it is for your budget! I didnt want to play around because of the stroker and my future plans for it..
I just bought a $525 9.5 inch lock up unit for myself. When the snow melts, it is going in
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From: Gulfport FL
One of the members on the other forum told me that when the stock ECM is removed, that the torque converter is controlled by the T.V. cable and governor pressure controls. Sound familiar to anyone?
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This info cannot be more wrong. When the ecm is removed, nothing will activate the lock up. It can be modified to lock up in a non computer application, but in stock form, no ecm=no lock up function.
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From: stop the fun suckers
Vigilante makes the Rolex of torque converters. Cannot take anything away from them. Reputation, power, quality is top notch. Price is tough to swallow. For the rest of us, the converters I use are great.
I just bought a $525 9.5 inch lock up unit for myself. When the snow melts, it is going in
I just bought a $525 9.5 inch lock up unit for myself. When the snow melts, it is going in
Post results of your new TC!
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I certainly will. I have only run my new engine combo 1 time, and traction was limited. On opening day, I want to work on hooking the car up and getting a solid baseline using the converter i currently have. It is a 12 inch model from the same company. After establishing a solid baseline, I will swap it out to see what kind of gain I truly get from the 9.5 inch. Because the stall is similar, I do not expect huge gains. Drivability should improve quite a bit and I hope et and mph pick up a tiny bit as well.
on your face!! IT was a huge grin on mine the first ride out the gate!
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I certainly will. I have only run my new engine combo 1 time, and traction was limited. On opening day, I want to work on hooking the car up and getting a solid baseline using the converter i currently have. It is a 12 inch model from the same company. After establishing a solid baseline, I will swap it out to see what kind of gain I truly get from the 9.5 inch. Because the stall is similar, I do not expect huge gains. Drivability should improve quite a bit and I hope et and mph pick up a tiny bit as well.
