Best tranny behind a built 283 with a 3.55 rear??

[burger]

I'm trying to select a 4-spd or 5-spd tranny to put behind the 283 in my '31 coupe. Desktop Dyno likes the engine to the tune of 325 HP / 315 FT-LBS. What would you put between this engine and a '55 Chevy rear with 3.55 gears connected to 31" tall tires? With 315 FT-LBS, strength isn't a real issue, so I'm more concerned about gear ratios. Anyone have specific experience with what tranny/rear gears they used with successful or undesireable results?


Thanks,
Ed

[Unkl Ian]

The average 283 doesn't have enough torque to pull an OD gear.Yours doesn't sound average.

[Ayers Garage]

31 inch tall tires and 3.55 gear won't really need an overdrive. The tall tires are going to effectively kill the gear somewhat.

[38Chevy454]

I agree that with 31 inch tires and 3.55 gear you will not need any OD. So the traditional Saginaw 4-speed would probably be a fine choice. Still easy to find and cost effective.

The newer T-5 would be a good choice as well, but you should go to a 4.11 or 4.56 rear gear, so you can cruise the freeway in OD at enough rpms that the 283 is happy.

283 like rpms. They are not a low end torque engine, like a 350 for example.

[burger]

I'm looking for someone to recommend a specific transmission (like a 3.11 first gear Saginaw or a 2.88 first gear T-10) or to maybe say, "I had good response with a 283 and a '74 Vega Saginaw, a 3.78 gear and 28" tall tires."


Ed

[Fat Hack]

Bass posted a cool reply on the old Saginaw tranny thread...the ratios can be determined by the number of grooves on the input shaft.

I'd recommend this one for your combo:

2 LINE INPUT - 3.11/2.20/1.47/1.00

That'll get that 283 up and moving quickly, and it should live in a light car with a smaller displacement small block...consider a lowly Saginaw!

[Deyomatic]

You can always go to the Richmond gears site and play around with their gearing calculator.

http://www.richmondgear.com/101032.html

[Tony]

I used a short first gear(3.11) saginaw in my '32.
It's running a 283 with 3.00-1 rear and L78-15 tires.

Low end is not all that bad, but if i was going to do it over,i would go with either a 336 ,355 gear.It would have much better response.

with my set up, i can cruise at 60mph and my tach reads around 1900rpm's. I deffinately don't need an OD..
It's livable right now because the motor's not exactly stock, and produces more than enough power ( it's prolly somewhere in the 400's on hp) to leave a light without bogging.

Just my own experience.

Tony...

[burger]

With the aid of CarTest [Download Here (http://www.cartestsoftware.com/cartest4.5/downloads/cartest.exe)] I was able to determine that a 2.90-ish first gear would give me the best 0-60 acceleration. The 3.11 is actually too much, or at least some computer program thinks so.

That leads me to the 0 groove Saginaw. Anyone got an extra?





Ed

PS- Tony thanks for the info. Since I have more gear (3.55), it makes sense that I might want a slightly higher first gear.

PPS- For anyone interested in screwing around with computer simulations, I recommend checking out CarTest. It's almost as fun as Desktop Dyno. Play with the 'Parameter Sensitivity' function if you want to see what the computer thinks would be the best gear, etc.

[choprods]

USE THE SAGINAW 4 SPEED WITH 3 RINGS ON INPUT SHAFT -[THATS THE LOWEST] FIRST GEAR- THAT WILL LET IT "LIVE".