[MidnightAuto]

I was able to get a fair amount of projects done this season before putting the car away. The last was having 3.36 gears and a posi unit installed. I wanted to add a bit more pull out of the hole with my m20 mated to a 421 tripower mostly stock. I knew highway would suffer a bit, and after driving, i am sitting at 2600-2700 rpm going 55. Not awful, but not great.

So I have been exploring options-swapping in a 5 speed, or maybe gearvendors overdrive. I’d love opinions. I would not be doing this work myself (I don’t have a lift) and from what I can tell a 5 speed is a 5-8k cost all in. Gear vendor od is maybe 2 or 3k less. Neither is a trivial sum. I also am not real interested in tearing up the floor a whole bunch for either option. So thoughts appreciated.

And if u know anyone that does this type of work within 100 miles of Westchester, ny. I’d love to get their names to get a quote.

[64speed]

The 5 speed conversion is not as much as you estimate. The full kit for my car from American powertrain was 4600 and that was every piece but the flywheel

[Half-Inch Stud]

4L80 fit my 1968 GTO. Highway RPM is grrreat now, with 3.54:1 rear gear.

[tom s]

What car is it going in?That can influence the cost.I have a TKO 600 in a 63 421 Lemans and a TKO500 in a first gen 69 bird.The bird was EZ as the only mod was to make the shifter hole a little bigger and use a 2nd gen boot and bezel.I had to shorten the drive shaft some.Most other cars need to have the floor modded to fit.My bird has a 3.31 in the back and is 70 MPH right at 2000 RPMs.Tom

[MidnightAuto]

Thanks guys. 70 at 2k is pretty sweet. It’s going in a 64 gto convertible clone.

64 speed- I was thinking all the parts is close to 5, and another 2-3k for someone to do the work?

[PDC]

I’ve got a mildly built 455 in front of the factory ‘close ratio’ M-22 with the 2.20 1st gear and a 3.42 ring gear. The motor has a streetable FT cam with box-stock Edelbrock D-Ports, Doug’s headers, and an RPM intake. I ended up re-building the stock M-22 Trans case with a set of M-22-‘Z’ gears from Midwest Muncie (2.99 / 2.04 / 1.46 / 1.00) with a 3.08 rear end. The gearing is a blast for a street driven car. The 2.99 1st x 3.08 rear = 9.20 overall reduction outta’ the hole. I would have needed a 4.11 ring gear to duplicate that 1st gear reduction with the 2.2 1st in the factory ‘close ratio’ Muncie M-22. And in top gear, I can cruise at 80 MPH at dead even 3k rpms. 70 is around 2600. The gear spread is wide, but that would be a bigger deal for a small block 302 Ford or a 327 Chevy. The torque from the long stroke Pontiac 455 literally gobbles up the gear spread in the wider ‘Z’ gear set. I’m sure that folks who race and are chasing every 1/10th would want to keep their car in a narrower power band. But for the weekender, the M-22 ‘Z’ with a 3.08 ring gear is a really ‘functional’ compromise. FWIW, my car will rip the tires loose from a roll in 2nd gear at 40 mph.

I have read on the forums of folks using the ‘Z’ gear set with 2.82 or even 2.73 rear gears. You’d need a 3.73 or even a 3.91 to duplicate that overall reduction with the 2.20 1st gear in a stock ‘close ratio’ (2.2) Muncie 4-speed.

FWIW I also have a car with a TKO 600 and a 3.23 ring gear. 1st overall is 9.27 and top gear with the .82 OD is 2.64. If I had that car to do all over again, I’d have gone with the Midwest Muncie ‘Z’ gearset and another 3.08 rear end.

[Tom Vaught]

I went the other way many years ago with a 2.75 Ford 9" rear gear and a Doug Nash 5 speed (5th is 1 to 1). With a 3.27, 2.13, 1.57, 1.23, and 1.00 final drive ratio and the much better supported counter-shaft in the trans, it is much stronger vs a typical newer style "rail transmission". Rear gears are strong with an excellent gear mesh and the driveshaft is a larger tube diameter with the better U-Joints. The Trans is also what was called by Doug Nash as a Equal Energy Split Transmission.

That being said, Doug has passed on, Richmond Gears had his trans for a while, and parts are now scarce. The TKO600 and TKO500 seem to be the best street trans out there with minimal tear-up of the body. I had no mods required on my 64 GTO convertible years ago.

75 mph (Michigan speed limit) I am doing 2200 engine rpm in 5th gear.

Tom V.

[tom s]

The Richmond is the best fit for the 64 IMO.Tom

[tom s]

Richmond makes a 5 speed with a .77 OD and a 3.33 first gear..Put a 3.08 in it and would make a great street trans,EZ off of a stop and a 2.37 final gear.What I did for my 62 421 GP I put a 3.42 first gear Richmond ST-10 four speed trans with a 2.68 rear gear.Wont take any racing or high RPM big sticky tire starts but I have used them in a 63 421 GP and now my 62 421 GP and have never brook one with stock street tires.FWIW,Would be a EZ switch for you with only a clutch disc change to a 26 spline input and a T-400 yoke.Tom

[242177P]

Originally Posted by MidnightAuto

So I have been exploring options ...

There's also the M23. They're in Syracuse.

[64speed]

Originally Posted by MidnightAuto

Thanks guys. 70 at 2k is pretty sweet. It’s going in a 64 gto convertible clone.

64 speed- I was thinking all the parts is close to 5, and another 2-3k for someone to do the work?

If your car is already a manual SST and American Powertrain have local shops they prefer in most places. My labor price was quoted at 600 with no seat or front carpet in it.

[lust4speed]

Silversport has a good sale on right now, and it was enough to knock me off top dead center to getting an order in. About a month ago we installed a TKO-600 in my friends 67 GTO and we had to only take a mallet to a small area of the tunnel - maybe a verticle strip 1x2 and a 3/8" deep to clear a corner of one of the top plates. Kit comes with everything needed including patch panels we didn't have to use. Price plus shipping to the west coast was $4,034.80 after the $300 off and I'm going to supply the 26 spline clutch disc, although their price was very competitive on it. The above price includes the driveshaft, miscellaneous parts, and 3 quarts of Tremec trans oil.

Tremec's TKO-600 has a 2.87 first gear and a .68 overdrive. I'm planning on also purchasing a Strange Dana 60 (hell of a sale going on there until December 3rd) with a 3.54 ratio. So first gear multiplication will be 10.16 which should also be good for pulling stumps or clunking along on the 91 Fwy coming home from a show down in Tom S's neck of the woods.

The problem with the Gear Vendors is after spending close to the current $3,000 on the unit you still have a 50 year old Muncie in front of it with a torque rating of 400 foot pounds or less.

[i82much]

I have an m23 super wide ratio, 3.54 strange s60 behind a hydraulic roller 505. i love it on country back roads but agree it is a bit much at interstate speeds. i would probably do gear vendors if i drove more on the interstate, but i live in eastern WA and the back roads here are made for relaxing drives in an old hot rod.

[lust4speed]

The above price included the $399.95 carbon fiber lined synchro's that saner people don't need if shifting below 6,000 RPM. But taking the synchro upgrade off drops the sales price below $4,000 so instead of $300 off, the discount between $3,000 and $3,999 is $250 so the math says it would have run $3,684.85 if I figured correctly. Shipping across the country was $179 which is included in that amount.

Mention that Mick Batson referred you, and if I get 40 people buying the kit my trans would be free.

edit - just noticed that the first paragraph in my last post got blown out. Was saying that we only had to take a mallet to a small area about 1x2 inches and only tapped in about 3/8" to clear just one corner of the middle top plate on the trans.

[Lemans64]

Another thing to consider is what Tire you are running. You can change tires diameter to lower the rpm. Just a cheaper way to change gear ratio. If I am doing a bunch of city driving I run a 245/60/15 with 3.9 rear gear, it's fun. But if doing highway I change the rear tires to a 255/70/15, it drops the rpm around 300 at 60 MPH. Just more food for thought. 26 inch tire to a 29 inch tire.

[Scarebird]

Originally Posted by PDC

...I ended up re-building the stock M-22 Trans case with a set of M-22-‘Z’ gears from Midwest Muncie (2.99 / 2.04 / 1.46 / 1.00) with a 3.08 rear end. The gearing is a blast for a street driven car. The 2.99 1st x 3.08 rear = 9.20 overall reduction outta’ the hole. I would have needed a 4.11 ring gear to duplicate that 1st gear reduction with the 2.2 1st in the factory ‘close ratio’ Muncie M-22. And in top gear, I can cruise at 80 MPH at dead even 3k rpms. 70 is around 2600. The gear spread is wide, but that would be a bigger deal for a small block 302 Ford or a 327 Chevy. The torque from the long stroke Pontiac 455 literally gobbles up the gear spread in the wider ‘Z’ gear set.

My "Z" has 2.93's i back, works very well

[lust4speed]

Whoops, one more correction to my first post. The TKO-600 overdrive ratio is .64 and not .68.

[steve25]

I would live with the rpm your at right now as your right in the center of the torque cradle that a 421 cid motor has at its disposal!

If anything you might go with a 1\2" taller rear tire.

Has any one ever noted as I have the difference in rpm between bald tires and new ones of the same type?

[Tom Vaught]

Originally Posted by lust4speed

The problem with the Gear Vendors is after spending close to the current $3,000 on the unit you still have a 50 year old Muncie in front of it with a torque rating of 400 foot pounds or less.

Many years ago, a Holley Friend with a 55 Chevy mated two Muncie 4 speeds under his 55 Chevy (in line).
He pulled a Large Dual Engine Boat with that 55 Chevy.

In his case he wanted the gear ratio plus the ability to get down the road once the car and boat were up to speed.

It packaged about like a Gear Vendors "add-on" to a regular 4 speed.
A Lot cheaper though at the time but he had Fabrication skills.
Think he had about $600 in the whole deal but that was in 1978 dollars.
He could leave the second trans in 4th gear and drive the car with the "forward" 1st 4 speed just like a regular vehicle.

There are some real benefits to "more than 4 speeds" in a Trans.
Ford, GM and Chrysler have all proven that deal with their new modern 6 speed, 8 speed, and 10 speed transmissions.

Tom V.

[Formulajones]

Originally Posted by MidnightAuto

I was able to get a fair amount of projects done this season before putting the car away. The last was having 3.36 gears and a posi unit installed. I wanted to add a bit more pull out of the hole with my m20 mated to a 421 tripower mostly stock. I knew highway would suffer a bit, and after driving, i am sitting at 2600-2700 rpm going 55. Not awful, but not great.

So I have been exploring options-swapping in a 5 speed, or maybe gearvendors overdrive. I’d love opinions. I would not be doing this work myself (I don’t have a lift) and from what I can tell a 5 speed is a 5-8k cost all in. Gear vendor od is maybe 2 or 3k less. Neither is a trivial sum. I also am not real interested in tearing up the floor a whole bunch for either option. So thoughts appreciated.

And if u know anyone that does this type of work within 100 miles of Westchester, ny. I’d love to get their names to get a quote.

You must have a super short tire on it. Even with a very short 26 inch tire and a 3.36 gear, 2700 rpm should be 62 mph.

That's really not a bad setup for highway. For years we drove 3.55's with an M-20 and 27" tires. It would cruise 65 right around 2800-2900 rpm. A 28" tire would be slightly better yet.

In any event, I do a ton of 5 speed swaps here and every single car I've done all I've ever heard is it's by far the best money they've ever spent on the car.
A car being a 4 speed already saves a bit of money. You should be able to do the swap under $4000 easily. The trans itself runs about $2600 and there are just a few things you would need on a 4 speed car, some are optional. Depends on what kind of car it's going in.

I've done a 5 speed swap for myself in the car previously mentioned that had the M-20. I kept the 3.55's out back, stuck the TKO-600 in it, a speedo cable adapter, a cross member, a reverse light harness, a short throw shifter body, and a 26 spline clutch disc, along with the correct billet yoke. I also opted for the sincro upgrades on the trans which added about $600 to the cost. I then took that yoke to my local driveline shop and had a driveshaft made with solid 1330 joints and seamless steel tube that is good for 600hp. Overkill but I wanted it. The trans stuff itself was almost exactly $4000 and I spent another $350 on the shaft. Worth every penny.
The car used to cruise town and highway with the M-20 and get 14 mpg around town and 17 mpg highway cruising at 65 mph and 2800-2900 rpm. Now it's getting a solid 15 around town, not much change there, but the last highway trip got me 21.5 mpg. It cruises at 65 at 1800 rpm and I can buzz along at 75 mph right at 2100 rpm. Major improvement.
I'm doing another 5 speed swap on my sons car now.