Consistency
 

I know this isn't a bracket site but I also know this is where the info is. Question: 70 Pontiac Lemans,350 c.i. built similar to stock rules, is a powerglide or a turbo 350 more consistant ? Also,car came with a b.o.p. 10 bolt. Is this rear worth putting any money in, or should I go with a 12 bolt ? I'm planning on trying stock in the future so I don't want to spend money where it's not needed. Car is not tubbed and is still in the building stage.It's basically a street car now torn down and getting cleaned,painted and ready for the strip.

Steve

I would take a long hard look at where you are going with your project & build with parts that will suit your later needs. Some cars never came with a P/G & only a 3 speed is allowed in those classes. No sense spending double.
my .02 for what it's worth

Adger Smith

Thanks for the response Adger. I thought some of the 350 engine cars came with the powerglide. If I'm wrong let me know. Thanks

Steve,

As Adger said stay as close to stock as possible..I do think they came with T-350, and yes the T-350 is the way to go...I would leave the tubs STOCK, don't touch them..You can still get a 30X9"
radial slick in there on a 10 "rim,with the right off-set....They made two 10 bolt rears, 8.2 and 8.5..The 8.2 is not very strong, but the 8.5 is what I use in my firebird and can handle a 455ci motor if set-up with good parts.You do need to decide if this is a race car or a street car ???? Good Luck Dave...1033/stock( 350)

Both Adger and Dave are correct. It does't appear that a Powerglide was available in 1970. The classification guide does not indicate a difference in shipping weights for TH, usually a clue that the PG was available.

c

Dave:
Is the 8.5 rear a direct bolt in for this car? If so,what cars did they originally come in? I'll start looking for one.What should I expect to pay for a stock one? Thanks

A 70 is an 8.2 . if you can find a lemans a few years newer it will be a an 8.5. the chevelle should be the same thing too.

novamoation

Re: Consistency
 

The easiest way to spot a 8.5 10 bolt is; it has square corners on the bottom middle near the rear cover.

Re: Consistency
 

Sorry bud, but you stepped into one of my pet peeves.

Pontiac did not use a Powerglide transmission, ever. Neither did Buick or Oldsmobile.
They did use a planetary two- speed known as the Super Turbine 300 ,or the Jetaway, depending on the brand. The only thing that's the same as a PG, is the gear ratio (1.76 PG) . The BOP trans is a stronger unit than the PG in stock form, but it never had any aftermarket support.
Calling one of these 2- speed transmissions a Powerglide would be no more correct than calling it a Fordomatic or a Powerflite.

Now , for your question. Put a Turbo 200 3 speed in it and look for a Chevelle , Monte Carlo or 70 GTO 12 bolt in it in case you ever want to use a 4.33 ring and pinion.

Re: Consistency
 

68-72 12 bolt chevelle/70-72 monte carlo rears will be a bolt-in (bring checkbook)
64-67 chevelles are an 1.5" narrower(bring 2 checkbooks)...
if you are not going class racing,i'd stick a 9" in it.
it'll be cheaper in the long run...

Re: Consistency
 

Sorry Mark, but you are wrong. At one point, in the early seventies, there was a major fire at the plant where the 350 was built. GM made PowerGlides with multi fit cases to be installed in the place of the 350 transmissions in all GM cars. I actually had one of those transmissions in a circle track car, a Pontiac Grand Prix with a 400 Pontiac, later a 428 Pontiac, and finally a 455 Pontiac. The case was a genuine GM PowerGlide case, and would bolt to a Chevy, a Pontiac, a Buick, an Oldsmobile, or a Cadillac, with no adapter. I had to have the case because there was a rule that stated no adapter could be used.

Re: Consistency
 

Alan ,I know that . I've seen them. .........I'll take a couple . Could you send them to me?
Thanks for confusing the issue .Now all the 2 speed Tempests and GTO's on Ebay can still claim they have a Powerglide in them.

How about Canadian Pontiacs? Transaxle Tempests? Technically a PG, I guess.

Hey everybody , Alan is right. Mark is wrong .Got it?

Re: Consistency
 

Hey Mark,

And don't forget that the SuperTurbine 300 had a TH400 size output.

Bob

Re: Consistency
 

Hey Big Guy, Thanks for some ancient history ,from an ancient....Never mind.

30 spline input too, so it takes a 350/400 converter where a PG does not.
That was the trick back then. Put a 6 cyl , ST300 converter in a T400 V8 car, and get about 2000-22000 stall.

Re: Consistency
 

If all the superstock guys are going to 3 speeds how could a powerglide be a faster trans in stock? You think a stocker motor makes enough tork to recover fast enough on the gear change with a glide? Turbo 350's seem to be the cheapest way to go. And you can't break the damn things...my trans builder built me 3 turbo 350's identical to eachother, one for my 9 second street car and two for my stocker. All stock internals except for the valve body, TCI sprag and some pump work. I can build 3 turbos (non lightweight) and have the same money invested in 1 powerglide. The gearset is what make it more expensive. Just my opinion.

Re: Consistency
 

Mark, I don't have any, I got mine from my friend Jim Beattie at ATI.

I didn't confuse anyone any more than you did. You said NEVER. That was not correct.

Don't take it so personal. Got it?

Re: Consistency
 

I build my own transmissions, and it costs me more to build a 350 for Stock than it does to build a PowerGlide. Of course, for Stock we use the lightweight parts in both transmissions. But the 350 has twice as many drums. And a low gear set for a 350 ain't real cheap, either. I suppose if you just built a 350 with nothing other than the sprag, it might be cheaper than a PowerGlide with a low gear set, but then that's not really a fair comparison, is it?

Re: Consistency
 

No problemo.
I just didn't think that was a good time to muddy the waters with that little known fact.
Shoulda known I couldn't slip it by you.

Re: Consistency
 

Alan and Mark,
Why can't you two get along as well while you're disagreeing with each other on this topic as you each do with others who have different political viewpoints?
Play nice.

Re: Consistency
 

We're getting along fine.:cool: Since when do drag racers play nice?