Thread: Need some input (again) guys - PG to TH400

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Guys,
Some of you might have seen from a previous post that I did a tran-brake launch with a converter that wasn't rated for a tran-brake. Nice show for the neighbors that were around, but frustrating for me. Now I'm faced with buying a better converter and having my PG gone through to ensure everything is still okay.

My question: Since I'm making this pure drag car ('68 Nova, 468/blower, around 600 HP) into a street/strip ride for my family, I'm being told that a TH400 would be a better choice since it would give me an additional gear and might even run cooler.

I'm finding a lot of 400's with brakes (still my choice to have one), that can run full manual, have JW bells, better pans, etc. It sounds like the time to make the switch but I'm wondering what else I might be getting into. Shifter, drive shaft work, crossmember, etc. Can anyone give me the pros/cons you've went through in the past so I don't have to go back to the school of hard knocks (again). I'm a manual-shift kind of guy but for a number of reasons I would like to keep this one an automatic, so I'm learning the slushbox lessons on-the-fly.

Thanks in advance for your input...

Hobo

Transmission chioce is up to you, PG or 400 are both excellent behind big horsepower for the strip. PG probably out numbers all of the other transmissions combined for pure drag cars with the 400 as a close second and the 400 might be slightly better for the street.
A stock converter won't hold up to a trans brake, there is just too much pressure build up and it will balloon but it sounds like you got to see that first hand. A converter designed to stall in the 3000rpm neighborhood would be a good starting place. Converters will stall at slightly higher or lower than the designed stall speed depending on horsepower etc....
You will have issues with your drive shaft length as the 400 is longer than the PG. Chances are your cross memeber may or may not need to be changed. Depending on the type of shifter you have you will more than likely have to get a new one. I run a B&M shifter that is like the Hurst Quarter stick and mine has an interchangable plate that can work with 400 or a PG.
Anyway there is my .02 cents.

The usual rule is light cars use glides, heavy cars use 400's... I would say the split in weight as about 2800 pounds.... But a tranny brake and 3000 stall on the street???? Wife and kids gonna cruise in it???? I've always preferred leaving the race car parts on the race car, and street rod parts on the street car... I hate comprimises!!!!!

I completely agree a choice must be made first....pure drag car or street car that goes to the strip every now and then.

Per the above and,

That's a light car with a lot of torque so you probably don't need such a high stall converter (if the cam is streetable). I would choose one that is also not slipping too much at highway cruising speeds.

Kitz

Thanks guys. My intent is to definitely make it a street car that "may" go to the local strip every now and then, so I can give up the trans brake (although it was fun while it lasted). I'll just keep the line lock for some extra burnout power during cruise-ins. I'm not hearing any overpowering reasons to make the switch from my PG to a 400 even for street use (from this board or those who I have spoke with locally), so I may just have the PG looked at by a local professional and purchase another 2800 converter for the street - and disable my t-brake!

Thanks again...

Kitz,
I agree with you, and I took out a 4000 stall unit that the previous owner had thought was "streetable" since he put in a tranny cooler. The lowest I was able to go without standing on the brake pedal with both feet was a 2800 stall unit from Coan, which worked fine until my second 4000 rpm launch with the trans brake (live and learn). The motor has a 286H Comp Cams bumpstick which isn't too radical, but I guess the TQ of the motor/blower is coming into play.

Thanks again guys. This board is especially great for the biker/wrench guys like me who have decided to take up muscle cars as part of their hobby!

Here's my 2 cents... I run a glide on the street and the strip. I have had it in a 93 cobra and then we built a chevelle, so we put the glide in it...
Its a pretty simple tranny... no high dollar insides except for the converter, trans brake and a hardened input shaft. the car is 3,645 pounds with me in it. It does really well, I do have a tranny cooler with a elect. fan. so that helps. car runs 11.60's @ 115. Now down where you guys live it runs 10.80's. I'm in Colorado. I believe both tranny's are good but the glide does weigh a little less, and of course less rotating mass. That is my 2 cents, Hope your next tranny holds on a little better.