deuce highboy

anyone running a 355 or 336 gear with a M21 closeratio 4 speed. I now have a 411 but is too low for any distance, would like to change without losing all of my torque, Thanks, Jackie

DZAUTO

What kind of a car???

rgbau140

Could you post the gear ratios for the tranny? I just put in a zz4 with a TKO 500 and I have a 3.36 in my 66. I dont have the seat of the pants acceleration I am looking for. I am leaning towards changing to a 3.70 or 4.11. I think with the overdrive I get around the high RPM's In 4th. the more real life expirences with 3.70's or 4.11's, the easier the choice becomes. currently there are a bunch of threads going on right now concerning rear end ratios - some wanting more pop and others not liking highs revs at highway speeds. doesnt seem like it should be so tough with an overdrive - yet there are a lot of people looking for an answer

Avispa

2.20 1st gear
1.64 2nd gear
1.28 3rd gear
1.00 4th gear

You can change it to an M-20 wide ratio: 2.52.; 1.88.; 1.46; 1.00 just by changing the main drive gear and the countergear.

JohnZ

You wouldn't like the 3.55 with that 2.20:1 low gear, and the 3.36 even less; if you had an M20, it works fine with a 3.36. There's no free lunch with 1st gear ratios and axle ratios - they either work together or they don't. If you want a highway traveling setup and good low-end torque, you need an overdrive transmission.

jim lockwood

I converted my '60 (which has a close ratio T-10) from 4.11:1 to 3.55:1 after driving it from South Carolina to California.

The change muffled what had been explosive acceleration. Even so, I'm well pleased with the end result.

Jim

isac

I have 3:55 and a M21 in my car and It's ok but 3:36 would be a real clutch killer in city traffic with a M21 , M20 and 3:36 would be a better choice imo.

Chuck Gongloff

I swapped out the original 4.11's in my 63 about 6 years ago when I was living in Maryland. Put in a 3.55 pumpkin......... I did it to cut down on RPM's at highway speeds.

Changed the whole character of the car for the worse.

After I moved to Florida, I swapped again and put the original 4.11's back in.

I did not like the 3.55's in my car. Tough to accelerate from stop lights, had to feather the clutch, etc.

Now, I have my "old" car back with the 4.11's.

Chuck

donbayers

John Z is correct.

My car had the 4.11 rear end. I wanted to change for the same reasons as you. I quickly found out that I needed to change my M-20 from a close ratio to wide.

Yes, it is probably not as exciting to drive from a performance standpoint but I'm happy now to be able to drive the thing around and cruise.

wmf62

i have a ZZ4, 3.36, and a 1.67 2nd gear (MY6 transmission); starts up and drives fine in 2nd... BUT only because of the monster low end torque of the ZZ4
Bill

steampunk c1

What model car and engine and tyre size?

wmf62

Me? or OP?

Bill

Railroadman

I'm guessing he's asking OP - who still has not provided that info.

DZAUTO

It is NOT unique to this forum. I never understand people who ask a legitimate question----------------------------------and then disappear!
Oh well--------------

This question, or frequently very similar type questions (engine/gearing combinations) often arise. And there are as many opinions as there are combinations.
I would truly prefer a 4.11 or 4.56 for fun to drive reasons. But with the abundance of Interstate hiways (I clearly remember when there was no such word as Interstate, and only a FEW turnpikes), as well as the price of gas, a high gear rear (or at least an overdrive) seems to be the best solution. But with a high gear rear, you need a healthy torque motor, or a tranny with a very low 1st gear. Big blocks make great torque motors, but I don't like the added frontend weight.
For me personally, the solution for torque is a BIG inch SB (383 at the very least) with very good flowing heads (alum is a plus for cutting weight) and an aggressive cam (hyd roller if it will fit into the budget). With a well built big inch SB which saves weight and produces plenty of torque, a wide ratio 4sp and a 3.08 rear makes a great combination. With that kind of combination, VERY MINIMAL clutch feathering is necessary (actually, almost none). The car still may not be a rocket from a dead stop, but once the rpm is above 1000-1200, you can be at 60-70mph with 1st gear in no time. Power shift to 2nd and you're suddenly looking at 100mph----------------------and only in 2nd gear!!!!! And yes, my 56 with a SB400 will do that.

deuce highboy

Its a 64 corvette coupe with a 383 stroker, M21 and 411s. I'm not at home and don't know tire size but they are 15s

deuce highboy

My 383 has pro-filer alumn heads with 208 valves, 577 hyd roller cam, dynod at 535 Hp, should have enough TQ. I was just asking the question about a 355 because i'm turning way to many rpms at 70 mph with the combo I have. I would like to drive it out of the city limits. the only way for any period would be to drive about 55

deuce highboy

64 coupe

steampunk c1

Tom is right wide ratio is more suited to stroker motor and that power will pull 3.08 with ease. But 5 speed wood be even better.

DZAUTO

Based on that information, I see two plausible options.
M20/3.08 rear, or, leave the 4.11 in it and install a 5spOD.

John BX NY

My 67 has the L79 plus M20 and 3:36 and it seems to be the perfect all around combo for me...