Muncie Transmissions, Close vs Wide ratio question

[Stuart F.]

Re: Muncie Transmissions, Close vs Wide ratio question

Me too! I drive mine with the transmission a lot - up and down shifting. I use the brakes only for a complete stop or hold on a hill, so to speak. With down shifting, I just hold my foot steady on the gas and drop it in the next lower gear w/o any perceptible engine speed change when I release the clutch. Nice and smooth. With my son's 78 p.c. w/ W.R., it is more difficult to do w/o engine speed up. I don't know if I explained that well, but when you hold your foot steady, obviously, the engine will speed up when you push the clutch in, and when you drop it in the next lower gear and let the clutch out the engine speed is perfectly matched to the speed of the car. Then you back off for engine braking. Even my restrictive exhaust system sounds pretty good, but I am tempted to slip on the set of Cherry Bomb muflers that I have in the garage and return to my youth, remembering the days of "window rattling". (I once was in a street race where I went through a measured quarter, then immediately started down shifting in anticipation of a R.R. crossing. The guys at the end of qtr. said their car windows rattled like crazy, like a shock wave! That was w/my 56 w/58 Fuelie engine and glasspacks).

Stu Fox

[Michael H.]

Re: Muncie Transmissions, Close vs Wide ratio question

Mike - I agree 100%!! The even gear spacing of the close ratio box is especially nice for matching revs during downshifting going into a corner.

I bought a new 68 Z28, came with a 4.88 rear and, of course, a 2.20/close ratio M21.
Loved the "tunes" that I could play with engine RPM sound both upshifting and downshifting. Just normal driving sounded like a Formula 1 car. Nice tight gear spacing.

That 4.88 made it way serious fast too! A friend bought a new 69 Z28 with a 3.73 axle and he couldn't understand why I was able to just absolutely destroy him drag racing.

I always thought a wide ratio was for the power steering/air conditioning crowd.

I do kinda like the 2.43 1st of the new BW boxes though, especially if used with a 3.55 or less.
Never liked a wide ratio Muncie. May as well just have a 3 speed. as far as I'm concerned.

[Bill M.]

Re: Muncie Transmissions, Close vs Wide ratio question

I have a 66 425 HP, 2.20 1st/close ratio and a 3.70 read. For me, that's the ultimate for a big block cruiser.

My 396 needs a little more gear than your 427!

[Bob S.]

Re: Muncie Transmissions, Close vs Wide ratio question

That 4.88 made it way serious fast too! .................................................. ..........................................
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I always thought a wide ratio was for the power steering/air conditioning crowd.

Wow....4.88's; that must have been a fast Z!! Ahhhh, the good old days when gas prices weren't......wait a minute, they were $4.00+, now they're at $1.60.....Maybe the good old days are coming back!??? Naw, I must be dreaming.

Mike, I'm glad it's you who said that about the "power steering/air conditionaing crowd", but I've never been interested in fully optioned Midyears either....

[Michael H.]

Re: Muncie Transmissions, Close vs Wide ratio question

Wow....4.88's; that must have been a fast Z!! Ahhhh, the good old days when gas prices weren't......wait a minute, they were $4.00+, now they're at $1.60.....Maybe the good old days are coming back!??? Naw, I must be dreaming.

Mike, I'm glad it's you who said that about the "power steering/air conditionaing crowd", but I've never been interested in fully optioned Midyears either....

The 4.88 was exactly what those cars needed to be quick. That and a set of the stronger 142 "service" valve springs made a LOT of difference. (the 5/50 warranty was important then too)

Nothing wrong with all the power options. I've had a few 65's and 67's with all the convenience stuff years ago. It just never was right for me though.

[John H.]

Re: Muncie Transmissions, Close vs Wide ratio question

The 4.88 was exactly what those cars needed to be quick.

Jerry MacNeish owns (and restored and races) Dave Strickler's National Champion "Old Reliable" '68 Z/28 in NHRA "E"-stock class, and won the 2004 U.S. Nationals with it; 3400# NHRA-legal car, pulls the front wheels and consistently runs 10.90's @ 121mph.

Gearing is everything with a 302 - Jerry runs a Jerico 4-speed with a 3.29 1st gear and a 5.57 axle; launches at 7500, is into 2nd before the 60' light, shifts at 8400, and goes through the traps at 8400.

[William V.]

Re: Muncie Transmissions, Close vs Wide ratio question

Enclosed is a spread sheet that shows the rpm vs the speed for the m20 and m21/22 in all four gears. The only difference between the m20 and m21 is the number of teeth on the input shaft and mating cluster gear input gear. The m22 is the same ratios as the m21. However it has more of a right angle gear cut and has heaver strength gears. For the m20 & m21, the rest of the parts are the same for same year and pin size transmission. The wide ratio m20 is best for the high ratio rears (3.08 3.36) the close ratio is best for the 370 thru 356. I find the 3.55 rear works well with both wide and close ratios.

I have this spread sheet in excel so rear ratios and tire sizes can be changed. I will email it upon request.

BV

[Duke W.]

Re: Muncie Transmissions, Close vs Wide ratio question

None of your ratios match production gearboxes.

Duke

[William V.]

Re: Muncie Transmissions, Close vs Wide ratio question

OOPS

I had been playing with the spread sheet and forgot I change the ratios.
The ratios in enclosed file are from a reproduction 1965 owners manual.

Thanks