Looking for a 700R4 expert...
Thread Starter
Team Owner
Joined: May 2002
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Looking for a 700R4 expert...
I'm having frustration with a Bowtie Overdrives 700r4 and have some questions about the 3-4 shift and torque converter effects on line pressures and idle rpm drop in drive.
Looking for some straight answers, PM me if you can help.
Everyone else's best suggestion is buying a new trans and t/c and carb.
Looking for some straight answers, PM me if you can help.
Everyone else's best suggestion is buying a new trans and t/c and carb.
Thread Starter
Team Owner
Joined: May 2002
Posts: 24,337
Likes: 25
From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
I fixed the problem with the converter signal wire being crossed with the temp sending unit, but it still drives horribly.
Idle drops 400-500 rpm from Park to drive, so I have to set the idle really high to keep it from stalling in Drive, and this is complicating my efforts on tuning the carb.
When shifting into 3rd, transmission drops into overdrive right away and usually won't come back out under throttle. The RPMS are really low at this point ~1400 RPMs and getting on the throttle will just cause it to sputter and backfire instead of downshifting. So I have to manually shift back into 3rd.
Shift points feel perfect on 1-2 and 2-3 shift. TV cable was adjusted by my seat-of-the-pants dyno.
I think the converter came with the trans from Bowtie overdrives, but I know nothing about it, except that it came packaged with a lockup wiring kit.
Idle drops 400-500 rpm from Park to drive, so I have to set the idle really high to keep it from stalling in Drive, and this is complicating my efforts on tuning the carb.
When shifting into 3rd, transmission drops into overdrive right away and usually won't come back out under throttle. The RPMS are really low at this point ~1400 RPMs and getting on the throttle will just cause it to sputter and backfire instead of downshifting. So I have to manually shift back into 3rd.
Shift points feel perfect on 1-2 and 2-3 shift. TV cable was adjusted by my seat-of-the-pants dyno.
I think the converter came with the trans from Bowtie overdrives, but I know nothing about it, except that it came packaged with a lockup wiring kit.
Race Director
Joined: Feb 2004
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If you wire it up temporarily as a 4th gear only lock up, it may help to isolate a lock up problem.
I wonder if the rpm drop from park to drive is related to the converter lock up?
On the carb stuff, I have seen the tv cable over extend at wide open throttle, (or close to it), causing the shift troubles. Sonnax makes a correction kit for this for little money $5 or so.
It is a spring that attaches to the end of the throttle end of the tv cable. It causes the last part of the cable to have progressive travel.
I wonder if the rpm drop from park to drive is related to the converter lock up?
On the carb stuff, I have seen the tv cable over extend at wide open throttle, (or close to it), causing the shift troubles. Sonnax makes a correction kit for this for little money $5 or so.
It is a spring that attaches to the end of the throttle end of the tv cable. It causes the last part of the cable to have progressive travel.
Thread Starter
Team Owner
Joined: May 2002
Posts: 24,337
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
The lockup wiring is fine, but maybe I'll put a light on it just to be sure.
I think the way its wired, it can only lockup in 4th.
Do you have any thoughts on the 3-4 shift? It'll shift into 3rd at say 2500 rpm (normal accel, low throttle) and then instantly drop into 4th and bog down to 1400 rpm and stay there.
I think the way its wired, it can only lockup in 4th.
Do you have any thoughts on the 3-4 shift? It'll shift into 3rd at say 2500 rpm (normal accel, low throttle) and then instantly drop into 4th and bog down to 1400 rpm and stay there.
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Race Director
Joined: Feb 2004
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The lockup wiring is fine, but maybe I'll put a light on it just to be sure.
I think the way its wired, it can only lockup in 4th.
Do you have any thoughts on the 3-4 shift? It'll shift into 3rd at say 2500 rpm (normal accel, low throttle) and then instantly drop into 4th and bog down to 1400 rpm and stay there.
I think the way its wired, it can only lockup in 4th.
Do you have any thoughts on the 3-4 shift? It'll shift into 3rd at say 2500 rpm (normal accel, low throttle) and then instantly drop into 4th and bog down to 1400 rpm and stay there.
For example, c4 l-98 cars with 2.59 gears and a superram would bog terrible.
The 3-4 shift could very well be the tv cable overextending due to the geometry of the pin location on the throttle shaft. I will try to dig up the sonnax corrector part number. It is cheap and fixes this condition properly most of the time.
Thread Starter
Team Owner
Joined: May 2002
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
If that was the case, wouldn't it be a problem in every gear?
Race Director
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Although that would seem to be the case, the common symptoms would be identical to yours. I have never run across the problem personally, but the fix was recommended by Dana at Probuilt.
Sonnax AS1-01K TV cable corrector is what you need. www.transmissionhead.com has it, but so would any sonnax dealer. Price is $5. I would give it a try.
The tv cable pivot pin typically has a range of motion from 4:00 to 8:00, or vice versa depending on the pull direction of the cable. Crossing the 4 or 8 clocking will slacken the cable and result in the pressure change.
Sonnax AS1-01K TV cable corrector is what you need. www.transmissionhead.com has it, but so would any sonnax dealer. Price is $5. I would give it a try.
The tv cable pivot pin typically has a range of motion from 4:00 to 8:00, or vice versa depending on the pull direction of the cable. Crossing the 4 or 8 clocking will slacken the cable and result in the pressure change.
Safety Car
Joined: Apr 2004
Posts: 4,532
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From: Lahaina Hi
I know what you are going through.I finally gave up and set my 700r4
to a reverse manuel valve body and a 9" TQ converter.
I did that because I was having the same problem as you.
I tried a thousand ways to set the tv cable and when I got it close a week or two later it would start to screw up again.I got pissed and floored it and burn up the trans.
I was using the holley levers and screw in cable retainers,for the carb,tried one of the levers for a dodge and ground it down,I later found out it was the angle like the throttle that was flexing and bending .I also had a problem with full throttle,I made a bracket and finally got the throttle cable just right and it runs great .
I thought by making the tv cable as tight as possiable that would make it shift like I wanted, but I lost my kool and just blasted it.
to a reverse manuel valve body and a 9" TQ converter.
I did that because I was having the same problem as you.
I tried a thousand ways to set the tv cable and when I got it close a week or two later it would start to screw up again.I got pissed and floored it and burn up the trans.
I was using the holley levers and screw in cable retainers,for the carb,tried one of the levers for a dodge and ground it down,I later found out it was the angle like the throttle that was flexing and bending .I also had a problem with full throttle,I made a bracket and finally got the throttle cable just right and it runs great .
I thought by making the tv cable as tight as possiable that would make it shift like I wanted, but I lost my kool and just blasted it.
Thread Starter
Team Owner
Joined: May 2002
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
I haven't had any time to mess with it much, although I found out my brake light circuit isn't working anymore, so the TC isn't getting an unlock signal. I'll fix that and do what Pete said, simplify the TC wiring, and put a light on the dash that tells me when it's locked.
The TV cable has an install kit from Barry Grant on there, but I'll check on the prev owner's adjustment.
After I fix the brake circuit, I'll wire up a low-vacuum release switch to the TC, and then consider changing the converter. Didn't all the cars from the factory have a low vacuum release switch for driveability?
Also, what's a good stall converter for a commuter truck with ***** that'll do some towing on occasion? I want good freeway mileage too, if that's asking too much.
The TV cable has an install kit from Barry Grant on there, but I'll check on the prev owner's adjustment.
After I fix the brake circuit, I'll wire up a low-vacuum release switch to the TC, and then consider changing the converter. Didn't all the cars from the factory have a low vacuum release switch for driveability?
Also, what's a good stall converter for a commuter truck with ***** that'll do some towing on occasion? I want good freeway mileage too, if that's asking too much.
Le Mans Master
Joined: Apr 2005
Posts: 8,077
Likes: 4
From: Scarborough ONTARIO
No, my tranny built by pete and this is just beyond nice what i expected, anyway check my sig for mods, i was having trouble with 3-4 shift too soon, mine is 3.54 gears and SR with 219 cam ...... i sent governor to pete and he modiy governor weights to 10 grms i think and now it shift perfect (3-4), no bog down.
Regarding TV cable u can just go to tranny guy locally, and tell him u need TV cable extender, its a small piece of plastic with a small spring attached to it, heck he might through u for free as too cheap.
Also if i remember Lockup is feed into chip when to lockup i might be wrong with this, but when i burned chip from Tjwong he asked me when i want lockup to occur at what speed, by default i think it comes at 50 mph. But hopefully pete k will resolve ur problem, give him little break he got a full time job too besides transmission.
Regarding TV cable u can just go to tranny guy locally, and tell him u need TV cable extender, its a small piece of plastic with a small spring attached to it, heck he might through u for free as too cheap.
Also if i remember Lockup is feed into chip when to lockup i might be wrong with this, but when i burned chip from Tjwong he asked me when i want lockup to occur at what speed, by default i think it comes at 50 mph. But hopefully pete k will resolve ur problem, give him little break he got a full time job too besides transmission.
Race Director
Joined: Feb 2004
Posts: 12,518
Likes: 19
No, my tranny built by pete and this is just beyond nice what i expected, anyway check my sig for mods, i was having trouble with 3-4 shift too soon, mine is 3.54 gears and SR with 219 cam ...... i sent governor to pete and he modiy governor weights to 10 grms i think and now it shift perfect (3-4), no bog down.
Regarding TV cable u can just go to tranny guy locally, and tell him u need TV cable extender, its a small piece of plastic with a small spring attached to it, heck he might through u for free as too cheap.
Also if i remember Lockup is feed into chip when to lockup i might be wrong with this, but when i burned chip from Tjwong he asked me when i want lockup to occur at what speed, by default i think it comes at 50 mph. But hopefully pete k will resolve ur problem, give him little break he got a full time job too besides transmission.
Regarding TV cable u can just go to tranny guy locally, and tell him u need TV cable extender, its a small piece of plastic with a small spring attached to it, heck he might through u for free as too cheap.
Also if i remember Lockup is feed into chip when to lockup i might be wrong with this, but when i burned chip from Tjwong he asked me when i want lockup to occur at what speed, by default i think it comes at 50 mph. But hopefully pete k will resolve ur problem, give him little break he got a full time job too besides transmission.
I am pretty sure that Kevin did not mean anything. He sent me a few pm's that I did forget to return. Sometimes, I misunderstand someones description of the problem as well. Regardess, hopefully we can get to the bottom of his problems and sort it out.
Although I carry the trans torch here on the forum, I know for fact that we have some part time lurkers here that are much more experienced than me, but do not frequent much. Hopefully this keeps it at the top for Kevin
Race Director
Joined: Feb 2004
Posts: 12,518
Likes: 19
I haven't had any time to mess with it much, although I found out my brake light circuit isn't working anymore, so the TC isn't getting an unlock signal. I'll fix that and do what Pete said, simplify the TC wiring, and put a light on the dash that tells me when it's locked.
The TV cable has an install kit from Barry Grant on there, but I'll check on the prev owner's adjustment.
After I fix the brake circuit, I'll wire up a low-vacuum release switch to the TC, and then consider changing the converter. Didn't all the cars from the factory have a low vacuum release switch for driveability?
Also, what's a good stall converter for a commuter truck with ***** that'll do some towing on occasion? I want good freeway mileage too, if that's asking too much.
The TV cable has an install kit from Barry Grant on there, but I'll check on the prev owner's adjustment.
After I fix the brake circuit, I'll wire up a low-vacuum release switch to the TC, and then consider changing the converter. Didn't all the cars from the factory have a low vacuum release switch for driveability?
Also, what's a good stall converter for a commuter truck with ***** that'll do some towing on occasion? I want good freeway mileage too, if that's asking too much.
9.5 incher will stand a few hundred more(3000 or so) and make similar, or less heat.
Intermediate
Joined: Mar 2007
Posts: 30
Likes: 0
From: COCOA BEACH FLORIDA
when i got my car it had a fresh new re-built stg II race tranny from maddog transmissions in tampa florida. Wow, that is a slick tranny. Check their web page. I believe they can ship to you or your local installer. Pretty funny web page also. Something like www.maddogtransmission.com I think.
Thread Starter
Team Owner
Joined: May 2002
Posts: 24,337
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
I measured it at 1.55" from the throttle shaft. This is using Bowtie overdrive's "TV Magic" for Demon carburetors. It allows for reclocking the TV attachment, but it looks like the radius stays unchanged.