Hello all. I am planning on replacing my 4.10 gears in my '65 studebaker for a 3.50 R/P set and a 4 speed muncie. Ive heard that with a 327/3.50 gears, that the combo would make my car really doggish around town. Would i be better off with a close ratio and 3.70 gears or a wide with 3.50 gears for my mild 327? btw my tires are 28" tall and i suppose the car weights around 3400 with me in it. Thanks!
Well I prefer a close ratio transmission if I can get one no matter what my rear gear is. You choose your rear dependent on the operating range of your engine. IE what is your usable power band. It what RPM range does it fall. And what you expect your car to do, is it an around town car or a road car or does it do both and you need a gear set that is a trade off. You next question is going to be how stout is your engine? Is it a wheezer engine or is it a healty bull? Here is something else to think about a 3.5 gear @ 70 with that tire diameter is going to have you turning about 3000 RPM so on the highway you are going to be taching some Rs. Not a problem if that is your engines sweetspot but if it doesn't like to run that RPM for any length of time you may want to choose a taller gear for highway use. Here is a link to a gear ratio and RPM calculater for you to play with. http://tri-5.chevyrides.com/rpm.php
The close ratio (M21/M22) 1st gear is higher than the wide ratio Muncie, I think it's a 2.20 ratio vs the 2.54 of the wide ratio. Many 327 s came from the factory and were just fine with a M20 without runnin a 4.10 gear
The close ratio was desired by the racers. The wide ratio was common on the street with higher gears than a 3.50 you will be just fine.
My channelled 5w had a mild 283 w 350 gears and a close ratio Muncie. Most fun to drive car I ever owned but, 1st seemed a tad high and 4th seemed a tad low but again I had a small motor. I could wind it till the fan blades on the generator would pull into the fan belt and still not be going really fast.
The close ratio was sold for racing where the shift rpm was really high. So that the rpm drop at each shift was less so the engine could stay wound up. 3.50ish rear gears and 28's are about perfect for all around driving. town and highway. 2.54 X 3.5 = 8.89 This is your starting off gearing. Close enough to the ideal 10:1, that is what the factories go for.
Wasn't going to chime in til I saw this 'cause that's exactly what I had in my 1st 5/W. 327/300 with m-21 wide and 9" with 390 posi. Very impressive off the line and just fine around town but never liked having to cruise at 60mph. Next time I would go 370-350 gear. far as close vs. wide, I think either is ok but like I said, my problems were about 4th gear not 1st. -Steve
FWIW, if changing trannies anyway, why not consider the 5-speed? It solves all the abovementioned problems. Gooder off the line, gooder on the highway. jack vines
I was thinking the same thing. Unless your motor is a lot stouter than most street motors, a World-class T5 would seem to be the hot setup. Get the one with 2.97 first gear, and you will have more than enough dig on the street, and a great cruising gear in fifth. If you think you will abuse it, a TREMEC is a good choice.
If you do alot of freeway/distance driving, go 3:08r/p. Not good for burning rubber, nor dragracing, but great on the freeway & you rowing through the gears. When I blew up my 3:73s in my 68 327/SuperT10 I went to 3:08 & enjoyed it much better. Yeah I wasn't able to peal out inbetween gears any more, but it didn't sound like it was stuck in 2nd when on the freeway. I do alot of freeway driving.
Like MATA, I went w/3:08 and a wide ratio Muncie. The car did weigh ~ 2700 but first was fine, and 4th was as overdrive. A perfect setup in balance between economy and decent acceleration.
You want to multaply your first gear ratio in your trans by your rear end ratio get as clsoe to 10 as you can.trans first gear ratio 2.54 x rear ratio 3.50 = 8.89 all most 9 should be ok
in a heavier car the wide ratio works best,but with all the 5 speeds laying around i would use one. I had a 65 impala 327/275 wide ratio 4 speed got noisy(bearings) switch to a close ratio and hated the car slow on starts had to slip the clutch.
I can relate about the generator fan. One night I was winding my 60 over 283 with a dontov cam and through a blade from the generator fan through the hood of my 55. After that I went to a bigger pulley on the generator. That little motor would never give up.
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