Can anyone tell me the reason for a reverse valve body, other than the fact you are shifting away from reverse? Someone said they are better for drag racing mechanically and better on the trans. Is this true and why?
Why a Reverse Valve Body?
- Thread starter Mopastor
- Start date
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I think the main reason is because it feels more natural snatching the shifter backwards. It always did for me. Since you are being pushed back in the seat from inertia, it's not as difficult to shift pulling back as it is pushing forward. As for any advantages mechanically, I don't know about all that. May be some truth to it. I've just never heard it.
'64 Cuda
Well-Known Member
Easier to shift because you aren't working against the force of the acceleration provided by your FANTASTIC MOPAR POWERPLANT. NO WAY, NO HOW to accidentally shift into neutral on your way through the gears (unless you do something that I just can't understand).
HemiEd
Well-Known Member
Those answers are good, but the main reason is to prevent disaster.
You are pumped, and your adrenalin sky high, so you go to high gear, woops, that is neutral, or worse yet, reverse.
By shifting away from disaster (neutral/reverse/park) the worst thing that can happen is to go into a higher gear and bog or slow down.
I learned this the hard way, by trying to be macho man and shift with a column shifter.
Also, one time the early Hurst Quarter Sticks had a blue cable that turned out to be defective, and my 383 went in the trees, and the monster tach memory said over 10gs.
You are pumped, and your adrenalin sky high, so you go to high gear, woops, that is neutral, or worse yet, reverse.
By shifting away from disaster (neutral/reverse/park) the worst thing that can happen is to go into a higher gear and bog or slow down.
I learned this the hard way, by trying to be macho man and shift with a column shifter.
Also, one time the early Hurst Quarter Sticks had a blue cable that turned out to be defective, and my 383 went in the trees, and the monster tach memory said over 10gs.
Guitar Jones
aka Angry Johnny
Well actually it's a matter of low band apply and shift timing. In the drive position the rear band is not applied in first. If you pull it into first this applies the rear band. While that sounds well and good these days, in the earlier days timing the release of the rear band and the application of the front band was a problem and created a momentary drag when shifting. This already happens in the 2/3 shift when releasing the front band and applying the front clutch. Eliminating the rear band apply in first gear provided a cleaner shift.
turbomopar
Well-Known Member
I heard u can do away with throttle linkage with a reverse manual valve body
Dodgeguy101
"Motor Whisperer"
that is correct.
HemiEd
Well-Known Member
You no longer need kick down linkage, but I bet you still want to connect your throttle.
71'DemonRon
Well-Known Member
If you do that, you will be rebuilding your transmission very soon(fried friction clutches or other damage) To eliminate the kickdown linkage you need a FULL MANUAL valve body, they are made in reverse and forward pattern. I have run both on the street & strip for years, some people don't like shifting all the time, it doesn't bother me.
Check out : http://coperacingtrans.com/ , John Cope is a member here.
Check out : http://coperacingtrans.com/ , John Cope is a member here.
fishy68
Tyr Fryr's Inc.
As long as the trans. shifts cleanly it's no problem but I can tell you it sometimes takes work to get a torqueflite to shift cleanly. As Guitar Jones said it's all about band release and clutch apply timing. A lot of guys think a hard, neck snapping shift is good when that's not always the case. Sometimes their feeling shift overlap which is extremely detrimental to a trans. It takes a well trained feel to tell what's actually happening.
..........If u leve off the kd linkage u will burn up the trans from low oil pressure.............if u tie it back, it will NOT shift out of 1st gear.......the govenor pressure cannot overcome the line pressure..............kim........
Are you positive about that? I don't see how the trans would know if it was tied back, or was just being held back by the linkage with your foot to the floor? Also, I drove my '67 Barracuda for 3 years with the kickdown tied back, and it still shifted hard when I pulled it. I only could drive it on the street due to the 4.88 gears. A high geared car would be doing 100+ mph. before it would go into high gear.
bad440
everything,all the time..
74fldart
Well-Known Member
Quote:
Originally Posted by oldkimmer
..........If u leve off the kd linkage u will burn up the trans from low oil pressure.............if u tie it back, it will NOT shift out of 1st gear.......the govenor pressure cannot overcome the line pressure..............kim........
Are you positive about that? I don't see how the trans would know if it was tied back, or was just being held back by the linkage with your foot to the floor? Also, I drove my '67 Barracuda for 3 years with the kickdown tied back, and it still shifted hard when I pulled it. I only could drive it on the street due to the 4.88 gears. A high geared car would be doing 100+ mph. before it would go into high gear.
thats true, the amount of travel the kickdown lever has directly affects the fluid pressure thus the shift points change when in drive. If you want to run with the KD linkage you must tie back the lever around 1/2 its travel so you would have a decent shift point when in drive.
i had a lokar kd cable on my last car and could never get it adjusted right and the 1st time i went on a ride in the neiborhood to try and adjust it i almost over heated the tran fluid because the trans was going into 3rd almost immedietly and slipping alot. when i got back home i was underneath the car and put my hand on the trans pan and almost burned my hand it was so hot. this was do to slippage and not enough fluid pressure because the kd lever wasnt making full travel.
Originally Posted by oldkimmer
..........If u leve off the kd linkage u will burn up the trans from low oil pressure.............if u tie it back, it will NOT shift out of 1st gear.......the govenor pressure cannot overcome the line pressure..............kim........
Are you positive about that? I don't see how the trans would know if it was tied back, or was just being held back by the linkage with your foot to the floor? Also, I drove my '67 Barracuda for 3 years with the kickdown tied back, and it still shifted hard when I pulled it. I only could drive it on the street due to the 4.88 gears. A high geared car would be doing 100+ mph. before it would go into high gear.
thats true, the amount of travel the kickdown lever has directly affects the fluid pressure thus the shift points change when in drive. If you want to run with the KD linkage you must tie back the lever around 1/2 its travel so you would have a decent shift point when in drive.
i had a lokar kd cable on my last car and could never get it adjusted right and the 1st time i went on a ride in the neiborhood to try and adjust it i almost over heated the tran fluid because the trans was going into 3rd almost immedietly and slipping alot. when i got back home i was underneath the car and put my hand on the trans pan and almost burned my hand it was so hot. this was do to slippage and not enough fluid pressure because the kd lever wasnt making full travel.
LH23H2R
Well-Known Member
Stupid question time on my part : Is this the same reason having to do with the infamous Sprag
( overrunning clutch ) , and its propensity to coming unglued ?
I'd heard that the reverse-pattern takes the load off of the Sprag ; is that correct ?
75dartsport
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I myself prefer the normal shift pattern, because you have the ability to shift into neutral at the end of the 1/4 mile. I have ran both but prefer the normal pattern.
needsaresto
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Chrysler did much the same with thier 426 column equipped cars the shift was away from nuetral and reverse or to the right. Im not sure if it was a manual reverse valve body though.
i put a lokar kit on my 73 duster...I put the allen wrench needed to adjust it in my pocket...went for a drive...and stopped to make adjustments until i got it where I wanted it....
bad440
everything,all the time..
i think i would rather let off the gas and let the engine help me slow down rather than putting it in nuetral gotta drive back to the lanes anyway...
daredevil
Well-Known Member
The reverse manual low band apply keeps you from blowing sprags from a freewheeling overrunning clutch is what I was told. Is this not right? I ran a Shift kit equipped stock valve body for 2 years no problem with the kick down wired back a little more than 3/4s and it shifted hard on my bracket car.
needsaresto
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I believe you also have to have reverse manual for a trans brake. If this is right it's mandatory for me. I had planned on it anyways..
daredevil
Well-Known Member
transbrake is your valve body
daredevil
Well-Known Member
This was posted by Chris Andrews. Read number two.
Exploding Torqueflites
--------------------------------------------------------------------------------
Why it happens, and how to prevent it from happening to YOU!
A few years back at a local dragstrip, I happened to be standing by the starting line when a racer in a 66 Dodge had his 727 explode right off of the starting line.
I went to his pit area to examine the carnage, there was a massive crater in the floorboard/transmission tunnel area. Luckily the racer only suffered from a sore ankle. We were discussing the possible causes, when he told me he broke the ring gear in the differential the week before. He mentioned that his "transmission guy" checked out the transmission afterwards and gave him the OK to put the car back together. To my surprise the "transmission guy" was standing in the racer's pit area. I told him that these transmissions are not supposed to explode if they are built with quality components and the correct techniques. He didn't take kindly to me offering up my opinion at the time, and he simply replied "If you race enough it will happen". That statement is flat-out WRONG.
Why it happens:
It all starts when the over-running clutch (aka the sprag) in the rear of the transmission case is damaged. The roller bearings will commonly "roll-over" the posts or fingers on the spring retainer. This action will cause the transmission's geartrain to over-rev the engine rpm multiplied by the first gear ratio, commonly 12,000 rpm or more. The stock OEM powered forged high gear/front clutch drum retainer will explode at approximately 9,000 rpm. The sprag can be damaged by one or more of the following:
1) Driveline failure such as:
-Broken ring and pinion
-Broken u-joint or u-joint straps
-Broken driveshaft
-Broken axle shaft
-If you have a driveline failure, remove the transmission and carefully inspect the case and tail shaft area for cracks. Disasemble the transmission and check the sprag in the back of the transmission case. If it is not damaged, it is recommended to replace the springs and rollers to be on the safe side.
2) Using a reverse manual or trans brake valve-body that does not apply the low/reverse band in first gear.
-Ask the manufacturer of your valve body if it has the low bandy apply feature. This is very important, and I blame the majority of transmission explosions on valve bodies that are not applying the low/reverse band in first. If your car "free wheels" in first (early turbo action valve bodies), it is not applying the low/reverse band.
3) Misuse/abuse on the street or strip in first gear.
-Remember you can only damage the sprag in 1st gear. Start your burnout in 2nd, and shift to 3rd. When on the street, repetitively getting in and out of the throttle while in 1st gear can damage the sprag.
In the photo above notice the two bent fingers on the spring retainer.
Photo courtesy of www.kbpi.com
Photo courtesy of www.kbpi.com
How to prevent this:
You can virtually eliminate the chances of having an explosion by using a valve-body that applies the low/reverse band in first gear. By having the low/reverse band applied in first, the band helps to "cushion" and protect the delicate sprag. Remember with low band apply, the engine will compression brake when the selector is moved from 2nd to 1st, so make sure your speed is substantially lower prior to shifting down to first.
It is also a good idea to replace the OEM powder forged high gear/front clutch retainer drum with a billet steel drum for the street, or a billet aluminum drum for "race only" vehicles. Although the aluminum drum is made from strong 7075 material it is not recommend for street use as it will wear quicker.
A bolt in sprag is a common upgrade for the racer's peace of mind. It will not, however prevent a transmission explosion. I would recommend the "Ultimate" sprag as an upgrade from the previous 4 bolt, 12 roller design. The "Ultimate" sprag is a 6 bolt, 16 roller design, with 4 extra springs and rollers to provide that much more sprag protection.
6 bolt, 16 roller design "Ultimate" sprag
Finally, all race cars should use a SFI approved transmission scatter shield to prevent debris from entering the vehicle should you have an explosion.
If you have any questions regarding this very important topic, please by all means feel free to reply here, PM me on the board, send me an e-mail or call me at 720-939-4896.
Thanks for reading,
Chris Andrews
__________________
Chris Andrews
Exploding Torqueflites
--------------------------------------------------------------------------------
Why it happens, and how to prevent it from happening to YOU!
A few years back at a local dragstrip, I happened to be standing by the starting line when a racer in a 66 Dodge had his 727 explode right off of the starting line.
I went to his pit area to examine the carnage, there was a massive crater in the floorboard/transmission tunnel area. Luckily the racer only suffered from a sore ankle. We were discussing the possible causes, when he told me he broke the ring gear in the differential the week before. He mentioned that his "transmission guy" checked out the transmission afterwards and gave him the OK to put the car back together. To my surprise the "transmission guy" was standing in the racer's pit area. I told him that these transmissions are not supposed to explode if they are built with quality components and the correct techniques. He didn't take kindly to me offering up my opinion at the time, and he simply replied "If you race enough it will happen". That statement is flat-out WRONG.
Why it happens:
It all starts when the over-running clutch (aka the sprag) in the rear of the transmission case is damaged. The roller bearings will commonly "roll-over" the posts or fingers on the spring retainer. This action will cause the transmission's geartrain to over-rev the engine rpm multiplied by the first gear ratio, commonly 12,000 rpm or more. The stock OEM powered forged high gear/front clutch drum retainer will explode at approximately 9,000 rpm. The sprag can be damaged by one or more of the following:
1) Driveline failure such as:
-Broken ring and pinion
-Broken u-joint or u-joint straps
-Broken driveshaft
-Broken axle shaft
-If you have a driveline failure, remove the transmission and carefully inspect the case and tail shaft area for cracks. Disasemble the transmission and check the sprag in the back of the transmission case. If it is not damaged, it is recommended to replace the springs and rollers to be on the safe side.
2) Using a reverse manual or trans brake valve-body that does not apply the low/reverse band in first gear.
-Ask the manufacturer of your valve body if it has the low bandy apply feature. This is very important, and I blame the majority of transmission explosions on valve bodies that are not applying the low/reverse band in first. If your car "free wheels" in first (early turbo action valve bodies), it is not applying the low/reverse band.
3) Misuse/abuse on the street or strip in first gear.
-Remember you can only damage the sprag in 1st gear. Start your burnout in 2nd, and shift to 3rd. When on the street, repetitively getting in and out of the throttle while in 1st gear can damage the sprag.
In the photo above notice the two bent fingers on the spring retainer.
Photo courtesy of www.kbpi.com
Photo courtesy of www.kbpi.com
How to prevent this:
You can virtually eliminate the chances of having an explosion by using a valve-body that applies the low/reverse band in first gear. By having the low/reverse band applied in first, the band helps to "cushion" and protect the delicate sprag. Remember with low band apply, the engine will compression brake when the selector is moved from 2nd to 1st, so make sure your speed is substantially lower prior to shifting down to first.
It is also a good idea to replace the OEM powder forged high gear/front clutch retainer drum with a billet steel drum for the street, or a billet aluminum drum for "race only" vehicles. Although the aluminum drum is made from strong 7075 material it is not recommend for street use as it will wear quicker.
A bolt in sprag is a common upgrade for the racer's peace of mind. It will not, however prevent a transmission explosion. I would recommend the "Ultimate" sprag as an upgrade from the previous 4 bolt, 12 roller design. The "Ultimate" sprag is a 6 bolt, 16 roller design, with 4 extra springs and rollers to provide that much more sprag protection.
6 bolt, 16 roller design "Ultimate" sprag
Finally, all race cars should use a SFI approved transmission scatter shield to prevent debris from entering the vehicle should you have an explosion.
If you have any questions regarding this very important topic, please by all means feel free to reply here, PM me on the board, send me an e-mail or call me at 720-939-4896.
Thanks for reading,
Chris Andrews
__________________
Chris Andrews
Guitar Jones
aka Angry Johnny
No, the reverse manual valve body uses the over runnung clutch for 1st.
And don't get me started on the exploding TorqueFlights. If you treat your trans right the chances of that happening are pretty slim but you should run a shield anyway. Never do a burnout in 1st gear, always start off in second and if you lose a rear end or driveshaft while in first always take the trans out and inspect/replace the over running clutch components. I prefer just to replace the inner race, springs and rollers.
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