Who's running a BB with an M-22?

[Paranoid]

What rear end ratio are you using and do you like the acceleration?

I'm running a 454 with an M-22 with a 3.36 rear and think my results could be better.

I did have an M-20 with my SB. When I swapped in the BB I thought it would work better with an M-22.

I'm thinking of switching to a 4.11 rear with the M-22.

 

[67HEAVEN]

Len,

As you know, the M22 (and the M21) have 2.20:1 first gears. Your old M20 had a 2.52:1 first.

I imagine your theory was that the torque of the 454 would easily overcome the difference. Now you're not so sure.....is that correct? Is it sluggish out of the hole?

The M21 / M22 gears were best suited to hi-reving Special Hi-Performance and Heavy Duty engines. Is your 454 one of these?

Have a look at this comparison sheet I made up when I was deciding which rear gears to use with my Richmond 5-speed (3.28:1 first). Maybe it will help you make a decision about which transmission.

 

[Paranoid]

Thanks for the chart Bob. My 454 is simply a rebuilt & built up engine. Not factory Spec High performance or heavy duty.

Yeah, it's a little sluggish off the line with that M-22. For now I think I'm gonna swap the diff to a 4.11 unit. That will give me 9.04 overall compared to 7.39 now. That'd be a 22% improvement! Even better would be that M20 with the 4.11's = 10.35!

I don't do much highway driving anyway, somedays I'm just glad to get it out of the driveway. :L

 

[67HEAVEN]

That will give me 9.04 overall compared to 7.39 now. That'd be a 22% improvement! Even better would be that M20 with the 4.11's = 10.35!

If your main concern is out of the hole acceleration, then your choice of the 4.11:1 rear should be a good one. The 9.04:1 overall, in first, sounds just about right for the street.

My 10.10:1, in first, means that I'm shifting to second quite soon.

Good luck.

 

[IH2LOSE]

I have a 1966 427/425 with a M21 with 411's in it.

Out of the hole exceleration is outstanding, But I give up the highway cruising.

Although I am not a highway cruiser type of guy I actually have a rebuilt third member with 3:23's in it
I was going to install but just never got around to it yet.

My thoughts are think of what you actually want, You know the old saying the grass is always greener. Before I built my 62 I just could not wait to install the new gears as taking the 66 to a show an hour away or so away was a nuisance because of the rpm the motor was spinning at highway speeds. I used to have to give the car gas to go down hill until i realized i could just throw in the clutch and roll down the hill faster.

Now that my 62 is done I drive that one more and its fun to jump in the 66 for some heart stopping excellerator

 

[Grizzly]

A little different Twist

I'm having similar issues with my coupe with a SB and 3.08 gears. I like to do parade work but it just fries the clutch. Just great for getting there though.

When I was prowling around Carlisle I came upon one of the transmission places, forget which, but he pointed out that I could swap out the tranny and get the same results as 4:11's in low and still have a high fourth gear.

If you subtract the price of a rebuilt diff, and/or a rebuilt trany (I have a bad syncro) the price becomes more attractive.

The other thing to note is that most of us are in this for the long haul and a lower numberically ratio has larger teeth just because there are fewer of them in the ring gear. That helps a little with reliability issues.

 

[Ken Anderson]

The M-22 works best with a 3.70. A 454 should smoke the tires at off idle.

 

[Tom Bryant]

The M-22 works best with a 3.70. A 454 should smoke the tires at off idle.

Agreed. Believe it or not I can still remember driving my '59. It has 3.36s in it with the built up 283. The dual carbs and Wolverine cam gave it very poor off idle torque so slipping the clutch to get moving was the norm. I slipped in a 3.70 and then I could just let the clutch out and go. The 3.70 wasn't that bad on the highway either and it improved accelleration a lot. Now remove the no torque 283 and plug in the monster 454 and the difference should be amazing.

My '70 El Camino 454 LS6 had 3.55s from the factory and could have been stronger off the line. I would have switched to 3.73s if I had not sold it in '73 but since it was my daily driver 4.11s would just have been spinning the engine too hard during out of town driving.

 

[Paranoid]

Thanks for the info & opinions.