old style forged cranks and pushbutton TFlite-- how much power before they fail?

[azazello]

hi all,

i know ive asked this question before, but it's been a while, so here goes:

anyone have any idea how much abuse the old style (pushbutton) TFs can be built to take? how about the old style cranks (you know, the ones that don't use a flexplate and bolt to the converter with studs and nuts! absolute pain in the ass trying to get separated!) were these the same components behind maxwedges? granted mine are '60 vintage and the motor is a 383, but take a guess...

is there anything in the design, metallurgy, etc that would prevent them from being used for performance applications?

the reason i ask is i'd like to keep the pushbuttons functional in my desoto. not that a hurst quarter stick would look bad bolted to the floor in front of the record player (yes, it has a record player), but i've got my new 4-spd GTX now to satisfy those cravings.....

so from what i can figure here are my options:

1) bore the 383 .030 or .060 over, polish the crank, lightweight rods and pistons, balance rotating assy, design it to be a high rpm motor and give up a little torque the longer arm would supply, indy SRs, nice cam, try to find an aftermarket converter or have one custom made that DOESN"T use a flexplate, rebuild the old TF and hope it holds up!

2) use the old TF, old crank and either bore the original 383 or more likely get a later 383 or 400, bore it out and offset grind the original crank (i think you can get 3.54" or so by offset grinding a B crank-- correct me if i'm wrong because you can take an RB crank out to 3.91" or so, right? the rod journals are the same size, B and RB right?) doing this would give 413-430+ inches depending on the combination, lightweight internals, indy SRs, cam, etc.... pray the old components hold up

3) put the old stuff aside (added plus of keeping original 33k mile components unmolested) and get a modern TF, 11" or so converter, 400 block and bore and stroke, hell all the way to 500" if i feel the need!

clearly in a perfect world the last solution would be the winner hands down... however, in reality there are some problems that solution 3 could introduce:

for starters, are the modern TF and old TF dimensionally equivalent? or am i going to need to shorten/lengthen the drive shaft and fabricate mounting brackets to get the modern TF to work in the car??

hopefully somebody has been thru this already and can give me some advice.

thanks
pat

[Doug Wilson]

I think 3 is the best route. I don't believe you'd have any fitment problems, but I'm far from expert about it. My choice is based on keeping your original components original, in case your taste changes someday and you want to put together a concours restoration. Either of the other 2 ways really screws you up on the futureside financials. ...dumb guess from Doug ...GOD BLESS AMERICA

[Doug Wilson]

Sorry!!! I meant any MAJOR fitment problems.

[transfixleo]

Going from memory now (uh oh) the TF is essentially the same if you are talking about the Aluminum case TF('62 up for 727). The gears are pitched a little different so swapping parts becomes an issue. There is a brake bolted on the back right? That is different from the newer versions. I think the two basic bell shapes are the same (what we used to call "Square Head" and "Round Head"). The VB is a little different as it has the Reverse Inhibitor Valve which would stick due to a little Governor Pressure being present and you could not go into Reverse but it functions the same. Bottom line is that it would respond nicely to a TransGo Reprogramming Kit just like a newer one but if you break parts it might be harder to come up with the right ones.