heavy engine braking & cheetah VB

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The reverse band has been adjusted too tight. It's gonna have to come back down.
 
67Dart273 said:
You seem to be missing some of the point

The OP clearly said THE CAR WILL NOT MOVE in 2nd or 3rd gear
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I read it, but he also stated in the original post that "(i've been shifting a wide range of rpms from about 2500 to 4500rpm)" which means the car does accellerate from low gear just fine and it appears to shift ok.

If we were to substitute a manual trans, based on his scenario, then shifting from 1st to 2nd at 4500 rpms and then letting off the throttle would produce the same compression braking he's described.

With a 3200 converter, depending on the gear he's using, it could take some fairly high rpm to get the thing to move from a dead stop in 2nd and, especially, 3rd... Since he also stated he's concerned about "over revving" his engine, I'm wondering if he's turned enough rpms to confirm the test.

Question 1: When you state the engine feels like it's "braking", are you continuing to accellerate, or are you letting off the throttle when you shift to the next higher gear to get these results ?

Question2: What happens when you accellerate under full power ? Does the car run through the gears and accellerate as well as it did before you changed to the manual valve body ?

Question 3: If your trans was doing fine prior to the installation of the valve body, it's unlikely the installation of the valve body caused the problem you're describing - unless the valve body was defective...

I only ask these questions, because I'd hate to see you remove and rebuild your transmission, only to find out later the "problem" you're describing is actually normal with the manual VB. I've gotten similar responses from fellow rodders who later stated it just took them a while to get used to the new unit.

Good luck with your trans and do let us know how it goes.

Southernman
 
Southernman said:
I read it, but he also stated in the original post that "(i've been shifting a wide range of rpms from about 2500 to 4500rpm)" which means the car does accellerate from low gear just fine and it appears to shift ok.

If we were to substitute a manual trans, based on his scenario, then shifting from 1st to 2nd at 4500 rpms and then letting off the throttle would produce the same compression braking he's described.

With a 3200 converter, depending on the gear he's using, it could take some fairly high rpm to get the thing to move from a dead stop in 2nd and, especially, 3rd... Since he also stated he's concerned about "over revving" his engine, I'm wondering if he's turned enough rpms to confirm the test.

Question 1: When you state the engine feels like it's "braking", are you continuing to accellerate, or are you letting off the throttle when you shift to the next higher gear to get these results ?

Question2: What happens when you accellerate under full power ? Does the car run through the gears and accellerate as well as it did before you changed to the manual valve body ?

Question 3: If your trans was doing fine prior to the installation of the valve body, it's unlikely the installation of the valve body caused the problem you're describing - unless the valve body was defective...

I only ask these questions, because I'd hate to see you remove and rebuild your transmission, only to find out later the "problem" you're describing is actually normal with the manual VB. I've gotten similar responses from fellow rodders who later stated it just took them a while to get used to the new unit.

Good luck with your trans and do let us know how it goes.

Southernman
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I'm glad you posted this, now I understand your thinking.

It doesn't seem to me, though that a 3K converter is high enough to be all that fussy, as some of the stock 340's were what, 2400-2450?

I do agree though, that unless he's messed with the band adjustments "terribly" that the problem is probably the VB and not the trans.
 
Dart, I agree with you, but the only thing we can discern is that he "changed the valve body" and now he's confused as to whether or not compression braking is a problem.

Without his input on driving style it's kind of a duck shoot and, again, I agree with you; it's either the valve body or an operator that is still getting used to reverse pattern manual shifts.

I just don't want to see a fellow rodder spend money unnecessarily. Again, thanks for the feedback.

Southernman
 
I contacted TA-cheetah gave them my specs. they said the reason why it is instantly brakes when I let off positive throttle (even at cruise throttle) is because the gear I have, which is a /6 highway gear that i have yet to change. they said many people rebuild/modify the rearend before the trans which is why people don't really experience the type of engine braking that i do. but they said that because if the highway gear, in order to run in 2nd the engine should be about 3500+ otherwise (like what was said) if the engine drops below about that amount the trans "thinks and mistakes for a downshift" and immediately starts to engine brake. but they said just drive the hell out of it and i'll be fine. so thanks everyone for your help. I appreciate very much. thanks again.
 
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