[Overdriv]

A friend gave me a Powerglide trans out of a 1967 Nova, 6cyl. My question is, is this a good candidate for rebuilding into a race trans? Is there info on the WWW that explains what needs to be done for these to race?

Thanks.

[56Maynard]

If the case specs out its good to use. You'd have to provide some estimates hp and tq numbers before anyone could determine what hardware to use on it. You could go to ATI' site and look at what they do for the various power levels.

[Overdriv]

Not sure what it will go in, but it would be for race purposes, probably behind a SBC.

[Chazmac]

99% of Powerglides can be made into race 'Glides. Do it every day. Internal mods and components needed are based upon the type of racing, car and motor combo.

[Overdriv]

Since you do this every day, I'd like to ask you a question.

I built a powerglide for a friends injected SBC Vega. When the throttle was flashed a bit the car would move forward just a bit. It worried the owner, but I always thought it was caused by all the very tight clearances I set. The trans made 330 runs before it needed freshened. Care to comment? I'm not at all sure that was the right thing to do.

[Chazmac]

Powerglides use the band for low gear (1st). When the trans is in neutral, the input shaft will still turn with the torque converter. The shaft is splined into the planetary, the drum in the trans is coupled/splined into the planetary (sungear flange) and will tend to turn. At idle (600-800 RPM) it generally stays at rest due to the other friction elements and the weight of the car. When the idle is elevated or the throttle is snapped open, the internal components of the trans spin faster. The band is called a triple wrap design because of its design. By nature these bands are also "self energizing" when exposed to rotation of the drum they surround. When you whack the throttle, the drum speed spikes, the band grabs onto the drum and the trans will act as if it is in low gear, causing the tires to turn or the car to surge forward. This is considered normal in Powerglides, even if a little dangerous. I recommend Park for engine tuning work or someone in the car, foot on brake.
By the way, 330 runs is excellent for a 'Glide in drag racing. And your answer/reply to his concern was, in effect, correct. Good job.

[willys36@aol.com]

I built one of those 6-cyl PGs for my son's '36 Pontiac. Machined the piston for a couple extra clutch disks (5 vs. the 3 in the stock clutch), installed a steel clutch hob to replace the cast iron one (they also make a tough aluminum replacement) and added a high strength input shaft. I used a stock band but they make fancy Kevlar replacements too. The 6-cyl unit didn't use an oil cooler, it had a fan built onto the back of the torque converter and had several 3" holes bored in the bell housing to let cooling air flow. I traded the non-cooler pump for a cooler equipped pump from a junk yard tranny and added the external oil cooler. The beauty of the 6-cyl unit is that it has a 1.82:1 first gear reduction compared to the 1.76:1 in the V-8 ones. This is a better ratio for a dragster. Then add the torque converter and valve body mods you want and it will handle a lot of power.

[Jeff@JWP]

The 6 cyl units did have the 1.82 gear ratio vs. the V8 1.76 ratio. The 1.76 is the desired ratio because it is much stronger. The 1.82 carrier is made of stamped steel which is very weak and flexible under higher HP applications. The 1.76 has a cast steel carrier that is much stronger. 90% of the aftermarket planetaries are based off the 1.76 carrier design. Depending on what the HP and weight of the car is, there are lots of modifications that can be made. We make almost every part for a powerglide in our shop. We can almost build a new PG frrom sctatch!

[matt167]

Is the internals the same on a later PG and say a '51 PG ( I have a fairly rare '51 Fleetline 4dr with the 235/ PG combo ) just wondering.

[Crosley]

Originally Posted by matt167

Is the internals the same on a later PG and say a '51 PG ( I have a fairly rare '51 Fleetline 4dr with the 235/ PG combo ) just wondering.

short answer is no.



Race power glides can be built with no OE parts. It takes money to go fast, how fast does a person need/want to go?