Shift Kit Help on Auto 700r4
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From: Vettemod.com For the C3 People
St. Jude Donor '06
Shift Kit Help on Auto 700r4
OK, Against my better judgement I added a B&M Shift kit. Wahoo, it allows ole Goldie to burn some rubber and get sideways in second.
BUT, just cruising, when easing off brake, shifting from 1st into 2nd gear, it is hard shift, as designed.
I mean hard shift!
So, we had to drill two holes a little larger,(No more than 1/64 bigger) pull out about three springs, swap a plunger and that was about it.
Is it possible to lighten up on the 1 to 2 shift?
Worst case, can I just go back to original setup eventhough two holes are a little larger?
Any advice is appreciated.
Thanks
tt
BUT, just cruising, when easing off brake, shifting from 1st into 2nd gear, it is hard shift, as designed.
I mean hard shift!So, we had to drill two holes a little larger,(No more than 1/64 bigger) pull out about three springs, swap a plunger and that was about it.
Is it possible to lighten up on the 1 to 2 shift?
Worst case, can I just go back to original setup eventhough two holes are a little larger?
Any advice is appreciated.
Thanks
tt
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From: Vettemod.com For the C3 People
St. Jude Donor '06
FYI, spoke with tech guy at B&M. (NIce folks) He said that it is operating as per design. Which is what I expected but was not looking for such a slam into 2 that I am getting at low acceleration. It is actually softer at a higher speed. The shift does not concern me, it's the 25 year old tranny 
He could not answer me on the main question as to what part of the tranny shift kit makes the hard shift / and how to soften it just a little.
He did say that you could reverse the process, except where the plate was drilled out would make things feel kinda funny and not as original. A replacement plate would be needed.
tt
He could not answer me on the main question as to what part of the tranny shift kit makes the hard shift / and how to soften it just a little.He did say that you could reverse the process, except where the plate was drilled out would make things feel kinda funny and not as original. A replacement plate would be needed.
tt
Team Owner
Joined: Jul 1999
Posts: 65,492
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From: Orange Park Florida
The gear ratio drop from 1-2 in a 700 is horrendous....from like 3.xx to 1.8? something, damn nearly 50%....and so any shift kit seeking to apply the gears quicker will necessarily feel rough....can't help it....
the 700 I had in my '72 here was same way....but I loved it....
problem with the 700 is the 3/4 clutch pack....and reaction/reduction?? shell,
I gave it up after some 8 years and did a 2004r, and it's MUCH better driving....MUCH better....
the 700 I had in my '72 here was same way....but I loved it....
problem with the 700 is the 3/4 clutch pack....and reaction/reduction?? shell,
I gave it up after some 8 years and did a 2004r, and it's MUCH better driving....MUCH better....
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From: Vettemod.com For the C3 People
St. Jude Donor '06
The gear ratio drop from 1-2 in a 700 is horrendous....from like 3.xx to 1.8? something, damn nearly 50%....and so any shift kit seeking to apply the gears quicker will necessarily feel rough....can't help it....
the 700 I had in my '72 here was same way....but I loved it....
problem with the 700 is the 3/4 clutch pack....and reaction/reduction?? shell,
I gave it up after some 8 years and did a 2004r, and it's MUCH better driving....MUCH better....
the 700 I had in my '72 here was same way....but I loved it....
problem with the 700 is the 3/4 clutch pack....and reaction/reduction?? shell,
I gave it up after some 8 years and did a 2004r, and it's MUCH better driving....MUCH better....
I will deffinatley look at the 2004r for the next one.
Thanks again
tt
Melting Slicks
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From: Orange Park Fl
Le Mans Master
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It's the slip between shifts that kills trannys.
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From: Vettemod.com For the C3 People
St. Jude Donor '06
Thanks guys, appreciate the info!
Had a question put to me, thought I would post up for others out there.
My comment.
This is my first experience with a shift kit. It does wake the tranny up, but as in the thread, I think due to the wide range of gearing on the 700r it does bag a little first to second at low rpm's and when you first drop it in gear, not end of the world stuff, but it does get your attention to the point my wife even notices it (referencing to a C5 and C6). At WOT it does not bang. (it does but cannot feel it)
I used the B&M kit, about $30 at Summit. I believe most hard core guys on the forum say use a Transgo kit, it is about $140.
http://store.summitracing.com/partde...5&autoview=sku
Nothing hard about the B&M kit, just go slow and methodically through it, it is not anything you rush on this one. It took me and my friend about two hours with the tranny on a bench, upside down. The B&M kit has fewer parts.
Just remember, your screwing with the tranny. Even it you get a spring wrong, I don't think it would be noticable / end of tranny, but you get something backwards, that could cause some damage. TAKE PICTURES as you disassemble.
Hope this helps
Terry
Had a question put to me, thought I would post up for others out there.
My comment.
This is my first experience with a shift kit. It does wake the tranny up, but as in the thread, I think due to the wide range of gearing on the 700r it does bag a little first to second at low rpm's and when you first drop it in gear, not end of the world stuff, but it does get your attention to the point my wife even notices it (referencing to a C5 and C6). At WOT it does not bang. (it does but cannot feel it)
I used the B&M kit, about $30 at Summit. I believe most hard core guys on the forum say use a Transgo kit, it is about $140.
http://store.summitracing.com/partde...5&autoview=sku
Nothing hard about the B&M kit, just go slow and methodically through it, it is not anything you rush on this one. It took me and my friend about two hours with the tranny on a bench, upside down. The B&M kit has fewer parts.
Just remember, your screwing with the tranny. Even it you get a spring wrong, I don't think it would be noticable / end of tranny, but you get something backwards, that could cause some damage. TAKE PICTURES as you disassemble.
Hope this helps
Terry
Burning Brakes
Joined: Jun 2004
Posts: 1,012
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From: Granbury, TX
I am writing this as my tranny sits at Hobart's Performance transmissions Midlothian (DFW area) Texas. I broke the 2nd gear clutch band on a routine accelleration. Hobart told me the TV cable was misadjusted and shifting too hard. BTW, I adjusted it per procedure in the manual. I did have a stiff 1st to 2nd shift, chirping the tires at partial throttle. He told me that was OK at WOT but puts a high load on the trans at partial throttle. I'm not sure I completely buy into this explanation but he said he would adjust the TV cable, measuring line pressure. I agree, the TV cable does control shift strength and will definately burn up a trans if misadjusted.
I'm not happy with a broke, supposedly high perf, trans after 8 mos but he is working with me on the cost. I pick up the ride this evenng and will advise if I hear any words of wisdom.
I'm not happy with a broke, supposedly high perf, trans after 8 mos but he is working with me on the cost. I pick up the ride this evenng and will advise if I hear any words of wisdom.
Le Mans Master
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From: Gladstone MO
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The 2-4 servo- (operates the band) is externally accessable. Pull the cover, and install the Corvette servo and pistons. Bigger pistons may soften the 1-2 shift. I'm not 100% sure, but it may be worth a shot..
Team Owner
Joined: Sep 2003
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From: eville in
I am writing this as my tranny sits at Hobart's Performance transmissions Midlothian (DFW area) Texas. I broke the 2nd gear clutch band on a routine accelleration. Hobart told me the TV cable was misadjusted and shifting too hard. BTW, I adjusted it per procedure in the manual. I did have a stiff 1st to 2nd shift, chirping the tires at partial throttle. He told me that was OK at WOT but puts a high load on the trans at partial throttle. I'm not sure I completely buy into this explanation but he said he would adjust the TV cable, measuring line pressure. I agree, the TV cable does control shift strength and will definately burn up a trans if misadjusted.
I'm not happy with a broke, supposedly high perf, trans after 8 mos but he is working with me on the cost. I pick up the ride this evenng and will advise if I hear any words of wisdom.
I'm not happy with a broke, supposedly high perf, trans after 8 mos but he is working with me on the cost. I pick up the ride this evenng and will advise if I hear any words of wisdom.
Safety Car
Joined: Oct 2004
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From: Minnesota
My 700r4 with a mild kit from NAPA does the same thing. It's the only thing I don't like about it though. There was a 700r4 website done by a guy in Norway whom if I remember correct was able to change shift points by messing with the governor. Maybe I can find it.
Race Director
Joined: Feb 2004
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Drop the 1-2 accumulator and remove the spacers. Install a white spring on top of the piston and test ride. If it is still too firm, replace white with a green spring. I suspect you will like the white spring.
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From: Vettemod.com For the C3 People
St. Jude Donor '06
I am writing this as my tranny sits at Hobart's Performance transmissions Midlothian (DFW area) Texas. I broke the 2nd gear clutch band on a routine accelleration. Hobart told me the TV cable was misadjusted and shifting too hard. BTW, I adjusted it per procedure in the manual. I did have a stiff 1st to 2nd shift, chirping the tires at partial throttle. He told me that was OK at WOT but puts a high load on the trans at partial throttle. I'm not sure I completely buy into this explanation but he said he would adjust the TV cable, measuring line pressure. I agree, the TV cable does control shift strength and will definately burn up a trans if misadjusted.
I'm not happy with a broke, supposedly high perf, trans after 8 mos but he is working with me on the cost. I pick up the ride this evenng and will advise if I hear any words of wisdom.
I'm not happy with a broke, supposedly high perf, trans after 8 mos but he is working with me on the cost. I pick up the ride this evenng and will advise if I hear any words of wisdom.
Oh crap!
The TV cable adds more pressure to the system as throttle position changes, easy enough. I thought about that and verified that I have a slight bit of slack in cable at idle. (as per design if the cable were to break, it would fail at this low pressure setting) The only other adjustment is the angle and radius as it attaches to the carb. I verified mine via a friend with an '81. I have a Edelbrock carb and using Lokar cables. If I hold WOT on carb, I do bring the TV cable to its full movement. Dang, now somthing else to be conserned about
Keep us posted, this is one to keep an eye on for sure.
tt
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From: Vettemod.com For the C3 People
St. Jude Donor '06
I have also thought about and looked at the kit from the standpoint that it allows for two settings, one for towing and one for street strip. The towing application applies a higher pressure but softer shifts. The spings in the accumulator are different for each of these applications. Good suggestion!Thanks
tt
Burning Brakes
Joined: Jun 2004
Posts: 1,012
Likes: 5
From: Granbury, TX
Oh crap!
The TV cable adds more pressure to the system as throttle position changes, easy enough. I thought about that and verified that I have a slight bit of slack in cable at idle. (as per design if the cable were to break, it would fail at this low pressure setting) The only other adjustment is the angle and radius as it attaches to the carb. I verified mine via a friend with an '81. I have a Edelbrock carb and using Lokar cables. If I hold WOT on carb, I do bring the TV cable to its full movement. Dang, now somthing else to be conserned about
Keep us posted, this is one to keep an eye on for sure.
tt
The TV cable adds more pressure to the system as throttle position changes, easy enough. I thought about that and verified that I have a slight bit of slack in cable at idle. (as per design if the cable were to break, it would fail at this low pressure setting) The only other adjustment is the angle and radius as it attaches to the carb. I verified mine via a friend with an '81. I have a Edelbrock carb and using Lokar cables. If I hold WOT on carb, I do bring the TV cable to its full movement. Dang, now somthing else to be conserned about
Keep us posted, this is one to keep an eye on for sure.
tt
The clutch band that locks up 2nd and then 4th gears has a hole on one end that a pin fits in to hold it in place against the tension provided by the actuator on the opposite end of the band. The pin had actually ripped through the hole
.This tranny was designed to hold 500 hp but Hobart told me excessive line pressure in stop and go driving is worse than WOT, because at WOT all the gears are under stress. At partial throttle, you have slack and then when hit it with stress it can break things. As I recall when my band failed, I had let off and then punched it again to merge with traffic.
I had adjusted my TV cable per procedure: retract cable, then advance throttle 100%....
When Hobart hooked up the pressure gauges he found line pressure was way too high at partial throttle so he pulled the cable forward about ¼ “ to get the correct pressure. He had me feel that the cable was slack and had stretched.
FWIW I would have a tranny shop adjust the TV cable using line pressure or maybe use a new cable.
Oh well, live and learn, spend more money......
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From: Vettemod.com For the C3 People
St. Jude Donor '06
The clutch band that locks up 2nd and then 4th gears has a hole on one end that a pin fits in to hold it in place against the tension provided by the actuator on the opposite end of the band. The pin had actually ripped through the hole.
This tranny was designed to hold 500 hp but Hobart told me excessive line pressure in stop and go driving is worse than WOT, because at WOT all the gears are under stress. At partial throttle, you have slack and then when hit it with stress it can break things. As I recall when my band failed, I had let off and then punched it again to merge with traffic.
I had adjusted my TV cable per procedure: retract cable, then advance throttle 100%....
When Hobart hooked up the pressure gauges he found line pressure was way too high at partial throttle so he pulled the cable forward about ¼ “ to get the correct pressure. He had me feel that the cable was slack and had stretched.
FWIW I would have a tranny shop adjust the TV cable using line pressure or maybe use a new cable.
Oh well, live and learn, spend more money......
.This tranny was designed to hold 500 hp but Hobart told me excessive line pressure in stop and go driving is worse than WOT, because at WOT all the gears are under stress. At partial throttle, you have slack and then when hit it with stress it can break things. As I recall when my band failed, I had let off and then punched it again to merge with traffic.
I had adjusted my TV cable per procedure: retract cable, then advance throttle 100%....
When Hobart hooked up the pressure gauges he found line pressure was way too high at partial throttle so he pulled the cable forward about ¼ “ to get the correct pressure. He had me feel that the cable was slack and had stretched.
FWIW I would have a tranny shop adjust the TV cable using line pressure or maybe use a new cable.
Oh well, live and learn, spend more money......
Awe man, bummer! Thanks for the update and heads up too. I will check my pressures tomorrow.
++++++++++++++++++++++++++++++++++++++++ +++++++++
I did some searching, I actually found the two springs removed form the actuator , dang it if one is not a little longer than the other, anyone care to tell me which one goes first? ie.e which one is 1-2 and which one is 3-4. One is orange and the other is black. Both of these are removed to put in the B&M kit. Spacers replace both of these.
Thanks!
tt
Race Director
Joined: Feb 2004
Posts: 12,517
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Awe man, bummer! Thanks for the update and heads up too. I will check my pressures tomorrow.
++++++++++++++++++++++++++++++++++++++++ +++++++++
I did some searching, I actually found the two springs removed form the actuator , dang it if one is not a little longer than the other, anyone care to tell me which one goes first? ie.e which one is 1-2 and which one is 3-4. One is orange and the other is black. Both of these are removed to put in the B&M kit. Spacers replace both of these.
Thanks!
tt
++++++++++++++++++++++++++++++++++++++++ +++++++++
I did some searching, I actually found the two springs removed form the actuator , dang it if one is not a little longer than the other, anyone care to tell me which one goes first? ie.e which one is 1-2 and which one is 3-4. One is orange and the other is black. Both of these are removed to put in the B&M kit. Spacers replace both of these.
Thanks!
tt
Squeeze them to see which is stiffer. Put the stiffer(I believe orange is stiffer than black) in the case bore. That is the 3-4 accumulator. Put the weaker spring in the 1-2 accumulator. It will likley be too soft. A white spring is my favorite in the 1-2.