So i'm building an L79ish(350hp) 327 for my daily '65 el camino(3200lbs or so). I have both a wide and close ratio muncie i can use, and i'm wondering on your imput on which ratio you would run. I'm figuring on a 3.73 or 3.90 in the rear, when i go thru that. Also i'm considering changeing to a M22 gearset in one(they have both wide and close), is everyone happy with their new M22 gear set? I should add, my work is only 10 miles and most of it is 50mph hiway with about a mile of city driving one way. Otherwise this will see windey backroad abuse multiple times a week, and occasional trips to the strip when i make it legal
Put the wide ratio in it for the ride to work, and the close ratio for the fun driving. Or figure out which is more important to you.
my brother-in-law's 70 chevelle runs a fairly stout 350 with 3.73 gears and he says the first gear on his close-ratio muncie is almost like a granny gear. hope that helps.
I bet you mean wide ratio. My '40 Ford Pickup had a 327 with a close ratio Muncie, 29" tall rear tires and a 3.56 rear axle ratio. I had to slip the clutch to start off in 1st gear. I pulled the engine and tranny and installed a mild 350 and a rebuilt wide ratio Muncie. Now it's fun to drive. Folks forget, but back in the day, those close ratio boxes usually came with 3.90 and 4.10 rear axle gears.
You will probably have traction issues on street tires anyway, with 3.73/3.90 rear gear, I vote close ratio...What tire height, 26/27"?
I've got 4.10's and a close ratio in a 67 gto. Not a friendly freeway car. But Short Burst Are okay. At 50 max on back road So should be fine. Posted using the Full Custom H.A.M.B. App!
The main difference your going to see is in low gear. The high gear ratios are the same in both transmissions. The built 355 in my '57 Chevy with a 3.70 does fine with a close-ratio. The Z-28 Camaro I had with a 302 and 4.10 gears, not-so-much.
I have a 327/365 in a 62 Corvette. I bought this engine as a crate motor from GM in 1977 and ran a close ratio M21 that I really liked from then until I believe 2008 when I changed to a new M22 wide. I have a 3.70 gear. I was going to use the M21 in a big block and figured I would try a wide with a 2.52 first gear with the 327 to see how it would perform. I am real happy with the M22 wide and would not think of going back to a M21 with a small block. The M21 has real advantages if you want to road race it (although Autogear now has a different set up with a M21 if you want to road race). Some say the M21 may be better at the dragstrip as you don't have the bigger drop from third to fourth and I cannot comment on that-maybe they are right. Maybe a M21 with a 4.56 gear may be better at the strip as well but if we are talking street cars then we have to realize maybe more of the fun factor I am looking for is with running through the gears and by the time I hit third I am already going over the speed limit. The M22 wide I bought has the following ratios 2.52, 1.88, 1.46 then 1. The M21 has a 2.2, 1.65, 1.24 then 1. I have all these figures in front of me as I am considering a new Autogear M22 wide for a small block project I am starting that will have a 283/270. Autogear has a wide with 2.559, 1.762, 1.366 then 1 and I like the idea of going with that 2.559 first gear. My 283 project is going to have a 4.11 and with the 2.56 I hope that it will be pretty responsive especially in first. When I made the switch originally from the M21 to the M22 wide I made no other changes and when I test drove the car I immediately liked the response in the first three gears. I would never think of going back and what is fun may be different from one person to the next. By the same token if I had a car with more torque like a big block I would rather go with the M21. If you want my vote go with the wide. Jim
Ok, if you are running l79, with a 351hyd cam, the decision is easy ....... M21. The 22 has straight cut gears and sounds a lot like a dump truck - no $hit. The boggiest advantage for a m22 is a stronger case, 1" main, and straight cut gear set. All that lends itself to taking a good beatong and not tearing up - but I'm talking about 450 plus big block kind of high rpm shifting at 5000 plus rpm on a regular basis. Imagine vintage fia road racing. The l79 is your best economical bet and it will take a pretty good beating and your l79 will like the ratio drop a lot better with the 21 and the final drive is the same. It will be much more fun since the gear drop is closer together with the 21. The 20 is a Grandmom trans best suited for a 300 horse or 250 horse with easy driving. if you are doing clutch dumping go with a 22 from auto gear with a steel mid plate and beat on it. Have your wallet ready for a good m22!
Just for a point of reference this is what Autogear states on their website. Granted they are in the business of selling new transmissions but for whatever it is worth. The M20 wide may be a bit different on the ratios and of course they are not as noisy as the original M22 close ratio transmissions. The new M22s are not as noisy as the originals although I do not find the originals all that objectionable but to each their own. M22 Standard Close Ratio -2.199-1.640-1.274-1.000 These are the ratios General Motors offered as a factory option. Best when used with deep axle ratios such as 4.11 and 4.56. Designed in the days of 40 cent gasoline, it's good for dragsters and limited street use. M22W Custom Wide Ratio (Available Spring '02)-2.559-1.752-1.366-1.000 We designed this gearset to run with more economical axle ratios such as 3.55 and 3.70. For cars that can handle it this is our recommended street ratio. M22X Custom Competition Ratio-2.199-1.506-1.174-1.000 We designed this gearset primarily for vintage racing on road courses where upper gear flexibility is more important than acceleration from zero. It can be used with very large street motors if the 1-2 ratio drop is not a problem. M22Y Custom Overdrive Ratio (Available Summer '02)-2.199-1.506-1.000-0.859 We designed this gearset in response to the many requests we have received for an "in case" overdrive. The overdrive 4th is noisy and less efficient when compared to the direct drive 4th in a conventional gearset but it can be used in cars where an axle ratio change is not practical or gear noise is not an issue.
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