[fal308]

What is the highest horsepower that the 3 spd can handle? I'm curious as our '71 R/T came factory with a 383 3 spd. This car was a military ordered car from Vietnam and the original owner ordered it for street racing for when he got home (he is/was a good ole boy from the Carolinas).
I think I want to leave it original for several reasons.
The pros and cons of spd vs 4 spd;
pros; lighter weight, less shifting (drag racing), ???
cons; gear availability for the street, mileage concerns (yeah, right ), ???

[Eddie]

With the stock tires or near stock traction, I dont think you have anything to worry about in the strength dept. If it were mine, I would put a 4-speed or better yet a Keisler 5-6 speed in there in a New York Minute! LOL But I can dig an original 3 speed 383 Magnum too!

[fal308]

Eddie, only two things keep me from turning it into a g-machine canyon carver (or Silver State Classic runner ). First is that the car is part of my wife's family. They've owned it since 1975 and were friends with the original owners, so the history is known from day one. Second is no $$$

[Eddie]

Then I would be build as much torque into the engine as possible with a nice flat torque curve. In other words, a near stock setup with good exhaust, strong clutch, steeper rear end gears like maybe a 3.91 would be a good choice. But then again, a swap to a four speed wouldnt be that costly, along with a 3.91 gear, vacum Holley or probably stock Carter 600 CFM and some thicker torsion bars, with rear sway bar wouldnt be that much more expensive than 'stock' and corner a lot better than the factory setup with minimal cost. I didnt mean a 'high dollar car' Barc, just something that will improve the driveability and outperform the stock setup without detracting from the original design too much. Drew's car comes to mind, then the next level would be something like Daves or mine, then Fabiens 'Mondo' setup,(which if I had the money and guts I would emulate)LOL

[Dale1035]

I wonder if the 3 speed was ordered to save on insurance costs. Back then insrance was a lot higher for a 4 speed.

[fal308]

Not sure of the ratiso offhand but perhaps a good setup for street racing? As I said before, he ordered it for street racing. No cruising or long distance stuff. Of course my mother-in-law used it as a daily driver while raising her kids. She's a gearhead too so I'm sure she got on it on occassion

[Follicly Challenged]

It's probably a fairly rare car, if delivered factory with the 3 speed manual trans, might be worth leaving alone, or keeping all parts intact, if you do convert to 4 gear ?
My 72 340 Challenger also came "factory produced" with a 3 speed manual floorshift also.
I don't race it, but I actually LIKE it after I got used to it.

Apparently of 1267 340 Challengers produced in '72, fully 910 were autos, leaving 357 manual trans cars.
Of these 357 manual Trans cars, it is suspected, less than 60 were 3 gears, as most being accounted for in Various Rgeistries were 4 gears, at a rate of 7:1 versus the 3 gear cars, although ACTUAL 3 spd manual production is unknown.
Seems more people were going for the "optional" 4-spd than the "standard" 3 gear.

Have you been able to determine production numbers on your car ?

[fal308]

From everything I've looked at and read, the best I can figure is that our car is 1 of 59.