Technical Need some tranny and rearend advice

I have built several T bucket roadsters, from 4cyl Datsun power-to-400+ c.i.d. They 'can' be a total blast to drive, steer and handle great, ride very good ... as long you you 'design' the car to do so.
#1. Build the car with a low center-of-gravity as well as overall height.
#2. Make sure the wheelbase is at least 105"
#3. I made a "Quarter-Eliptic-3 Link" rear suspension that rode fantastic. ( One car we did with torsion bars at it rode awesome)
#4. Be certain to allow for plenty of radiator area to properly cool your engine.

Your 472 Cadillac and the matching T-400 trans will make it a rocket ship in stock form (I'm not kidding)
As to rear end choice, I've used Ford 8", Ford 9", MoPar 8-3/4". I've found that a 2.70-ish rear gear ratio is perfect for most V8 engines..... you can run all day down the highway and not beat your self up or your engine.

Here is a couple of pictures of a T-roadster from back in the 70's, study the overall look, suspension, axle,etc... this car is awesome, and I still think I would love to build one similar to it yet today (without the costly Hemi).
I also made convertible tops and side curtains (removable with velcro) for my cars because I drove mine in any kind of weather, even snow.

If you do it right, your going to have a ball with it. And if you don't, well ..... then don't waste your time and money.

 

Holy shat, I'm dying here.

 

Me either. Maybe he's mixing up the BOP trans as dual bolt pattern?
Anyhow, speedway and tons of other places sell an adapter for $40 bucks so a Chevy short tail shaft 400 is a bolt in deal. I'm sure torque converters still bolt up, but maybe with spacers?

To the OP, define, or clarify "expert advice" as it relates to the internet.....and the thread title......

 

First of all, intros are no longer a requirement; Ryan dropped that policy some time ago. Personally, I just prefer the profile is filled out completely; "name, rank, and serial number", as it were. As far as the TH400 goes, the short shaft extension housing and output shaft can be swapped in place of the long shaft unit. That's all I've got.
I am Butch/56sedandelivery;.

 

Squirrel I've seen several, I worked at a large salvage yard for 18 yrs, up until the early 90's. We srapped I don't know how many 400 turbos, wasn't no market for them, they very seldom went bad. Wish I had saved several of them along with a bunch of other stuff I seen go.

 

Interesting. wonder what years they were made? I've seen dual bolt pattern 200-4R and TH350, but never a 400.

 

My 2 cents is that you need a 3 or 4 speed trans in that rig like
a hole in the head. Go find a ST300, which is a sort of an HD powerglide
[also came with a VP converter in earlier years, and uses 300-400
converters] Shorter, lighter and all you'll need. BOP used them for years.
A note in passing: saw exactly one dual BP ST300. No idea why GM made
it, came out of an Olds, sat in the rack for years and finally went behind a 396. Transgo never made a shift kit for them, but they had a 2 page handout that made them shift pretty good.

 

The Ford Explorer 8.8 a good axle and has a 3.25" tube and 31 spline axles. For a T bucket I would use the 1990-1994 ones with 10" drum brake. You don't need, or want, too much rear brake.

 

picked up the beast today. Wasn't sure the year this came out of but after checking the numbers, it looks like it was a 68-69?? Block number 1486238

 

I had a 70 chevy short box step side with a 500 caddy and rear axle. You could twist it and roast the tires at will!