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Discussion Starter #1
Hello, all. New guy, here.

I came across a 1971 Nova with a powerglide and a B&M Prostick. I know nothing about the history of this car (long story). I am trying to figure out if it has a manual valve body. I’ve never driven a car with a manual valve body transmission (or with a Prostick for that matter). I’m also trying to figure out if it is a reverse gate shifter.

What is the easiest way to determine if the transmission shifts automatically, or if I have to shift it manually? I’m assuming it has the normal shift pattern of PRNDL. Shall I just put it in drive and see if it shifts? At what approximate RPM should I feel the shift? How do I determine if it is indeed a reverse pattern? The car has a big cammed 383 and what I believe to be a 3,000 stall speed torque converter, but not confirmed.

Please excuse my ignorance. I’d appreciate any input you have to offer. Thanks in advance.
 

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if it's a reversed valve body drive is 1st 2nd is 2nd and yes you have to manually shift it like a standard and no it will not automatic shift...if it is a racing built transmission the motor will drop to idle while coasting...and it's a pain in the ass on the street
 

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Discussion Starter #3
if it's a reversed valve body drive is 1st 2nd is 2nd and yes you have to manually shift it like a standard and no it will not automatic shift...if it is a racing built transmission the motor will drop to idle while coasting...and it's a pain in the ass on the street
Thanks for the quick response. If I’m understanding, a reverse valve body is the traditional shift pattern PRNDL front to back, so I would pull the shifter into ”D,” to start from a complete stop (low/1st), then shift backward into second, correct?

If I am approaching a stop, can I just stop and THEN shift down to 1st, or do I have to actually shift to 1st BEFORE I stop?

Thanks, again.
 

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Discussion Starter #4 (Edited)
if it's a reversed valve body drive is 1st 2nd is 2nd and yes you have to manually shift it like a standard and no it will not automatic shift...if it is a racing built transmission the motor will drop to idle while coasting...and it's a pain in the ass on the street
To correct myself, a reverse pattern is PRNLD, correct?
 

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Thanks for the quick response. If I’m understanding, a reverse valve body is the traditional shift pattern PRNDL front to back, so I would pull the shifter into ”D,” to start from a complete stop (low/1st), then shift backward into second, correct?

If I am approaching a stop, can I just stop and THEN shift down to 1st, or do I have to actually shift to 1st BEFORE I stop?

Thanks, again.
yes...drive is 1st...you can shift anytime you want between gears...city driving you will never get out of 1st unless you have a steep rear gear but if you do go to the next gear you have to shift back to the drive spot to get to 1st gear again...you can shift to 1st before a stop even if yer going really fast as long as yer not applying power
 

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By the way, I forgot to mention—the car also has a trans brake. Does this confirm it is indeed a manual valve body?
That does indeed confirm it is a manual valvebody...nobody makes an automatic shift transbrake valvebody. Transbrake valvebody's are all manual shift.

Now all you have to do is confirm shift pattern....put it in the regular "D" position....if it starts out an 1st gear you'll know ii is reverse pattern, and that the "L" position is now high gear.
If you put it in "D" and it starts out in high gear, you'll know it is still retaining forward pattern.

You can down shift at low speed coming up to a stop, or wait until stopped and downshift....I wouldn't recommend a downshift at 30 MPH coming up to a corner. It won't overrev the engine but I know with the TH-350 and TH-400 trans it is a big no-no, as it overspeeds the intermediate drum and can scuff the sprag.
Guys who have shifted back to second in a race full manual 3 speed after the finish line thinking it is just another neutral since there is no engine braking feature have had the drums explode since they got to 1-1/2 times driveshaft speeds when you do that.

I don't know of the 'Glide suffers from an potential overspeed situation like that or not.
 

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Powerglides are not reverse pattern manual valve bodies. They keep the stock pattern and 1st is all the way back. Push forward for high gear. The turbo 350-400 was a reverse pattern. Yes I know with all the high hp cars trans patterns are all over with clean neutral trans and what not, but assuming a run of the mill street/strip stock case trans its stock pattern.
 

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Discussion Starter #10 (Edited)
yes...drive is 1st...you can shift anytime you want between gears...city driving you will never get out of 1st unless you have a steep rear gear but if you do go to the next gear you have to shift back to the drive spot to get to 1st gear again...you can shift to 1st before a stop even if yer going really fast as long as yer not applying power
Awesome. Thank you. Been raining here and I’m not about to drive it in the rain, so I’ll test it out when this rain stops. Car has what I believe is a 2.73 8.2 rear. I’m also looking forward to driving it on the highway.
 

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Discussion Starter #12
That does indeed confirm it is a manual valvebody...nobody makes an automatic shift transbrake valvebody. Transbrake valvebody's are all manual shift.

Now all you have to do is confirm shift pattern....put it in the regular "D" position....if it starts out an 1st gear you'll know ii is reverse pattern, and that the "L" position is now high gear.
If you put it in "D" and it starts out in high gear, you'll know it is still retaining forward pattern.

You can down shift at low speed coming up to a stop, or wait until stopped and downshift....I wouldn't recommend a downshift at 30 MPH coming up to a corner. It won't overrev the engine but I know with the TH-350 and TH-400 trans it is a big no-no, as it overspeeds the intermediate drum and can scuff the sprag.
Guys who have shifted back to second in a race full manual 3 speed after the finish line thinking it is just another neutral since there is no engine braking feature have had the drums explode since they got to 1-1/2 times driveshaft speeds when you do that.

I don't know of the 'Glide suffers from an potential overspeed situation like that or not.
Thank you. Great information.
 

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I've run manual shift automatics on the street for a long time. Once you get familair with it, it's not all that different then running a manual trans.

I will say a Powerglide with just 2.73 rear gear is going to be less than inspiring on initial acceleration, that's for sure....most guys drag or even street/strip with a 'Glide consider even a 3.73 not enough gear, and 3.90 or 4.11 just barely acceptable.
A buddy runs his with 5.13 gear and 29.5" tall tire, it boogies to mid 10 second 1/4 miles for a fun street/strip car.

Was the guy you got it from setting up to run the Maxton Mile or Bonneville or something with those 2.73 gears?
Or just a work in progress and they hadn't got to the rear axle modifications yet?(odd combination of a t-braked 'Glide with a 8.2" rear)
 

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Discussion Starter #16
I've run manual shift automatics on the street for a long time. Once you get familair with it, it's not all that different then running a manual trans.

I will say a Powerglide with just 2.73 rear gear is going to be less than inspiring on initial acceleration, that's for sure....most guys drag or even street/strip with a 'Glide consider even a 3.73 not enough gear, and 3.90 or 4.11 just barely acceptable.
A buddy runs his with 5.13 gear and 29.5" tall tire, it boogies to mid 10 second 1/4 miles for a fun street/strip car.

Was the guy you got it from setting up to run the Maxton Mile or Bonneville or something with those 2.73 gears?
Or just a work in progress and they hadn't got to the rear axle modifications yet?(odd combination of a t-braked 'Glide with a 8.2" rear)
I don’t know the owner—I bought the car from a consignment dealer that specializes in classic cars and hot rods. Looks like the previous owner didn’t finish up the suspension and brakes but put all his money in the engine first, that’s for sure. Big cam 383. I took it for a spin and if it does have a 2.73, it still puts you in your seat. I’ll open it up, eventually, to verify. I did some research on it and I believe it was an original 6 cylinder, but it DOES have multiple leaf springs. I thought the 8.5 was not available on the Nova in ‘71?
 

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Haha! I want to give it a chance. Wanted a 4 speed but I couldn’t pass this car up. Why do you not enjoy it?
just shifting gears in a street environment with a automatic is annoying up and down all the time manually...if I just leave it in 1st at 35 mph I'm turning 3500 rpm ...not a cruising rpm shift to 2nd then the light turns red shift back to 1st and start all over...you never get to relax...it's like driving a tractor
 

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A powerglide takes a lot of gear and a lot of converter to make it work. I ran 4.88’s and a 5500 converter in mine to go mid 10’s at 3360 lbs and my dad was a similar converter and 5.13’s with a 32” tire going 9.60’s at 2800 lbs.
 

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just shifting gears in a street environment with a automatic is annoying up and down all the time manually...if I just leave it in 1st at 35 mph I'm turning 3500 rpm ...not a cruising rpm shift to 2nd then the light turns red shift back to 1st and start all over...you never get to relax...it's like driving a tractor
sometimes I just leave it in 2nd(drive) and it takes off fine doesn't feel much different (have a big convertor and steep gear) problem is the convertor gets tight in drive and it doesn't like to idle at a stop light in that gear
 

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Discussion Starter #20
sometimes I just leave it in 2nd(drive) and it takes off fine doesn't feel much different (have a big convertor and steep gear) problem is the convertor gets tight in drive and it doesn't like to idle at a stop light in that gear
I thought It was a big no-no to take off in second gear?
 
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