A833 NP A body trans ID help & intro.

to Twister
Check out Rob's build; that is gonna be a real nice street engine.
Don't underestimate the 360 cubic inches for a streeter. With cams from 220 to 235 that's just a 3 size range, you can go from more bottom end to more top-end, than the stock or even near-stock chassis can handle.
And just recently, YellowRose revealed that 170 psi can be run with iron heads and pumpgas, so that's news to most of us.......... That should make an interesting combo.
There are several engine builders on this forum too, so check out the Sponsor forum.
As for;
It's a normal box and am curious around what year it is.
I think 1970 was the last year of that box. In 71 they changed to steel forks, different brass rings, and the rooster-comb cover.
The first year I can't remember; probably early 60s, but I don't think it came to the A-bodies 'til a lil later.
973 Duster Twister Cali car, 318
The 73 318, I call a smoggerteen, cuz the compression was dropped to 8/1. In this condition they are fine with the stock cam and gears.
But the instant you jump to a performance cam, the cylinder pressure tanks, and then yur looking at slipping the clutch longer and more gear. In my experience, the smoggerteen at 8/1 likes 3.91s at least with that 2.66 low trans. This is even before you slide a cam into it! The 3.09 Commando low offers 16% more TM in first gear, so can use 16% less rear gear or down to 3.23s. The penalty for that is that all the other gears are similarly 17% lower numerically.So you might have to rev first a lil higher before shifting. At WOT, you don't get into third until 5000 rpm which is 65 mph with 27s so not a big deal. All-in-all a fair deal. To recap; stock smoggerteen,the Commando 3.09 low box, with 3.23s, and valve springs to allow 5000 without losing control.
3.55s are a lil better than 3.23s; the only penalties being 5000=59mph, and cruising moves from 65=2610 to 60=2650. Surprisingly, my smoggerteen did pretty good on gas at these Rs...... with a lean-tuned TQ, headers/dual exhaust, and a Smallport dualplane intake; Ignition timing is a key.