Reverse manual valve body questions

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I didn't, the trans was done 1 year (11 passes) ago by the previous owner. I'll inquier on the price to change to a forward manual VB

I'm half way between a NHRA and IHRA track and expect to try both ... I need to get a better education on the shifter rules if different.

The Duster has the B&M. Had the Hurst in a Florida Pro/Truck
Not happy with shifters that take two hands to operate.
 
70 Buster 340 said:
For some reason I'm afraid to try it in the traps.... and over rev.

maybe moving the valve fast enough through 2 and 1 .... can get away with it.
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Shifting to neutral on a torqueflite at high speed is risking a drum explosion at high speed if it's a 727. If you want to do this you must get a valve body equipped with a safe neutral. A safe neutral keeps the forward clutch engaged so the front drum cannot over rev.
These valve bodies also only come in reverse pattern and have another neutral after 3rd gear. If you neutral a standard valve body at high speed, all the clutches and bands are turned off and the front drum will over rev and possibly explode!
 
John Cope has the trans brake valve body like that with clean neutral. It is a reverse manual valve body. U don’t need to hook up the trans brake I don’t think. Even if u had to u wouldn’t have to use the brake. U would have to ask John. He is a member on here. John@CRT. Kim
 
Thanks Duane.. super helpful.

For sure.. I'll be coasting it out in high.
Is it best or mandatory to come to a complete stop before moving the lever back through 2nd and to 1st?
 
oldkimmer said:
John Cope has the trans brake valve body like that with clean neutral. It is a reverse manual valve body. U don’t need to hook up the trans brake I don’t think. Even if u had to u wouldn’t have to use the brake. U would have to ask John. He is a member on here. John@CRT. Kim
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You have to hook up the brake because these valve bodies have reverse and neutral sharing the same shifter position. To get reverse to come on, you have to push your transbrake button to engage the
Reverse clutch.
 
oldkimmer said:
Duane, that’s y I said u would have to ask JC. Kim
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Agreed, but all the safe neutral brakes work the same regardless of brand because they are all activating the same clutch.
You are correct that he does not need to use it to launch the car, but you need it hooked up to get reverse.
 
Trying to wrap my brain around this...
So if RMVB was designed as a safety/consistency/convenience/be cool feature for OEM non-ratchet/non-slapstick shifters and then safety ratchet shifters came along why didn't the FVB make a comeback.
Then you wouldn't need a PRND12N.
What shifters have the 6th position?
I would assume that is a 'lock-out' position .. correct?
 
what i have read and learned the reverse pattern is easier to make into a manual valve body...and the performance is better....
call one of the valve body manufacturer...i am sure they will tell you why........
 
It is also easier to pull the shifter than it is to push it when ur planted back in ur seat. Also without the rear band applied u get a quicker 1-2 shift. Kim
 
Duane said:
Shifting to neutral on a torqueflite at high speed is risking a drum explosion at high speed if it's a 727. If you want to do this you must get a valve body equipped with a safe neutral. A safe neutral keeps the forward clutch engaged so the front drum cannot over rev.
These valve bodies also only come in reverse pattern and have another neutral after 3rd gear. If you neutral a standard valve body at high speed, all the clutches and bands are turned off and the front drum will over rev and possibly explode!
Click to expand...


There are two different terms being used, "clean neutral" & "safety neutral". The Clean Neutral position after 3rd exhausts all bands and clutches. This position has the potential to cause an explosion. There are many companies that offer this option. If you use Aluminum drums you will not have a problem usually. The Safety Neutral position after 3rd exhausts all bands and clutches EXCEPT for the direct clutch (Large clutch drum directly behind the pump used for Reverse and 3rd). Keeping the 3rd gear clutch applied locks to the forward clutch hub and sun shell (exhausts forward clutch allows engine to idle) maintains all the internals spinning safely at engine rpm preventing over speed condition. You must keep the engine running for this to work. The only transbrake I know of that had this option was the Griner 12/22G25 model. This model is more difficult to manufacture and increases cost. Mainly used on high rpm engines with aluminum rods.
 
oldkimmer said:
It is also easier to pull the shifter than it is to push it when ur planted back in ur seat. Also without the rear band applied u get a quicker 1-2 shift. Kim
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Some of the trans brake makers are now claiming that with the billet style valve bodies and the a&a solid low/reverse piston that they can now get a clean 1-2 shift with the band on. John Cope explained to me that with the billet valve body, they can open up the size of the passages and increase the piston return spring pressure so that the band release is not noticeable.
 
DusterW2 said:
There are two different terms being used, "clean neutral" & "safety neutral". The Clean Neutral position after 3rd exhausts all bands and clutches. This position has the potential to cause an explosion. There are many companies that offer this option. If you use Aluminum drums you will not have a problem usually. The Safety Neutral position after 3rd exhausts all bands and clutches EXCEPT for the direct clutch (Large clutch drum directly behind the pump used for Reverse and 3rd). Keeping the 3rd gear clutch applied locks to the forward clutch hub and sun shell (exhausts forward clutch allows engine to idle) maintains all the internals spinning safely at engine rpm preventing over speed condition. You must keep the engine running for this to work. The only transbrake I know of that had this option was the Griner 12/22G25 model. This model is more difficult to manufacture and increases cost. Mainly used on high rpm engines with aluminum rods.
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I have the tranzact safe neutral but I not sure on the style of neutral. What sold me on it was an article on David Rehers forum
Where he explained how the oil timing built into a connecting rod journal is by design meant for the rod to be driving the crank
and the hydrodynamic oil wedge is formed from this motion only.
When you ride the car down in 3rd the crankshaft is driving the rods and the loading on the rods is not timed to be driven this way.
This is also happening when your oil pressure is not ideal either.
The article is a good read.
 
Acc
DusterW2 said:
There are two different terms being used, "clean neutral" & "safety neutral". The Clean Neutral position after 3rd exhausts all bands and clutches. This position has the potential to cause an explosion. There are many companies that offer this option. If you use Aluminum drums you will not have a problem usually. The Safety Neutral position after 3rd exhausts all bands and clutches EXCEPT for the direct clutch (Large clutch drum directly behind the pump used for Reverse and 3rd). Keeping the 3rd gear clutch applied locks to the forward clutch hub and sun shell (exhausts forward clutch allows engine to idle) maintains all the internals spinning safely at engine rpm preventing over speed condition. You must keep the engine running for this to work. The only transbrake I know of that had this option was the Griner 12/22G25 model. This model is more difficult to manufacture and increases cost. Mainly used on high rpm engines with aluminum rods.
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According to this tci press release, clean neutral and safety neutral are the same thing.

image.png
 
Thanks, that’s a great read. I have slowed down in gear all my life and have never had a crank problem. Same with hauling campers, boats, and any other kinds of trailers that almost require u to down shift a gear or 2 when decending a steep grade. Never a problem. I put EFI live into my diesel truck, when slowing down pulling a load it down shifts on its own. Just stating what I lived and learned. Kim
 
oldkimmer said:
Thanks, that’s a great read. I have slowed down in gear all my life and have never had a crank problem. Same with hauling campers, boats, and any other kinds of trailers that almost require u to down shift a gear or 2 when decending a steep grade. Never a problem. I put EFI live into my diesel truck, when slowing down pulling a load it down shifts on its own. Just stating what I lived and learned. Kim
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Me too, but I was buying a new transbrake anyway and I already had a shifter that would work with a safe neutral valve body, and the safe neutral was only an extra $25-50 dollars to get so I bought it.
 
Duane said:
Tech Talk #99 – More About Oil: A Slippery Subject
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See lol .... Just another reason to head for neutral in a coast down. Cooler motor, clean plug read and now clean bearings too.

Clean , safe, over speed drums, disengaged bands, push the button and neutral is the new reverse, air shifting ... wheew this is getting very complicated.
Hmmm, the 3rd pedal is still in the car.... looks like that's where the fun is ... but at the cost of consistency and the cash payout.

Mama always told me not to look into the sights of the sun
Oh, but Mama, that's where the fun is
 
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