gleninsandiego

How does the Muncie in a 63 compare to a Muncie in a 69 when it comes to strength?
Any difference?

I was going to put the rebuilt 383 engine and rebuilt Muncie 4 speed from my 69 into my 63.
However, it turns out the 69 Muncie is different than the 63 when it come to the shifter
The shift levers bolted to the trans are a different shape and bolt on differently




It look like I can't simply swap out the brackets as they don't fit




So there are several ways to go here
I see they sell a Hurst shifter that bolts to a 69 Muncie that looks like a 63

https://www.corvettecentral.com/c2-6...-muncie-532041

Sooner or later I was going to rebuild the original 63 and put it in the car
So I could do that right now and sell the 69 Muncie, which apparently has little value due to everyone
putting in 5 and 6 speeds

Which brings us back to the question, any difference between the 63 muncie and the 69 muncie
when it comes to handling the power of the 383, which I will say is about 400 hp?

Finally, is the hurst shifter that much better than the stock 63 shifter?

Thanks
Glenn in San Diego

plaidside

The 63 Muncie has a 7/8" diameter counter shaft and the 65 has a 1" shaft, So I will say the 65 is stronger in that respect.
Also some of the other differences I can remember is the front bearing retainer on the 63 is aluminum, not good, and the shift levers have 5/16" studs whereas the 65 has 3/8" threads and used bolts. I assume GM made these changes because of failures in the older boxes.
Joe

cardo0

There's still some dedicated Muncie vendors and the sky is the limit for upgrades. Add iron mid plates and fancy Italian gears to make it an M22 "rock crusher" if you want it. But it reads like you just want to rebuild it and maybe replace the operating levers.

Looks like MamotorWorks has the '63 levers but they don't have a rounded center of the slot like your '69 levers have (I guess you know if you need to drill them out). Take a look: https://www.mamotorworks.com/corvett...linkage-696168. Much cheaper than buying the Hurst shifter. But I've had the Hurst shifter upgrade on my list for a long time. Hurst advertises a shorter throw and I was under the impression it shifts straight up to 3rd gear but I can't find that in the literature now.

Let us know what you find please.

silver837

I think it depends on how original you want the car to be. The 63 Muncie is the weakest Muncie ever installed in any corvette (mid production in 63). The 63 input shaft bearing retainer is smaller than any of the other year Muncie,s so you would use your 63 "only" bell housing. If you go with the 69 Muncie you would need a different bell housing.
If you have upgraded the engine output you would be well served with the newer Muncie. There are plenty of members with more knowledge of this swap than I. I am sure they will step up.
Keep in mind 69 muncie,s were installed in the C3 cars and the shifter arrangement is different.
CardoOs post gives good advice. It's like many other changes that are made to these cars, you can make it work if you spend enough time researching and money buying the correct parts.

gleninsandiego

Giant step back

The 383 engine, bell housing, and Muncie all came out of my 69
So I do have that bell housing
and shifter for that matter, but I am not thinking that is of any use

What is different in all of this is the clutch fork
The clutch fork for the 63 has a different end on it

Plus I see the Clutch fork ball stud is different for a 63 and a 69 bell housing

So now the question becomes, can I use the 63 clutch fork in the 69 bell housing,
assuming I could put a 63 clutch fork ball stud in the 69 bell housing

silver837

I am thinking out loud here. The bellhousing of any64 and later C-2 will accept the 69 muncie. Look at the speedometer cable hook up on the 69 vs 63. The actuator rod for the clutch fork is a 63 only part. They changed it in 64 and up. The 69 fork has a clevis arrangement with a pin.
You may only need a bell housing and fork from a 64 up car to make it work.
Look at a Vendor catalog or other reference material for clarification.

GTOguy

This is incorrect. the '63-'65 Muncies have the smaller 7/8" counter shaft. The '63 has a one-year-only, weak small front bearing retainer. It's a rare box these days, good for a numbers matching car, but it is inferior to the '64-'65 units. Now, you mentioned you have a '69 unit. A '69 Muncie is far superior to a '63 in strength. The '66-'74 Muncies all had the beefy 1" countershaft. If I were in your position, I'd probably swap covers/levers or just use a Hurst shifter and run the '69 stuff.

Frankie the Fink

I have the Hurst shifter on my anemic 63 original Muncie and I prefer it....

I always hear, and understand from an engineering standpoint, that the 63s are weaker but I don't hear tons of stories about them blowing up....they were the same behind the F/I engines in '63 right ? and the Z-06 ?

GTOguy

Correct. They were the weakest Muncie, but still stronger than the ST-10 of that era. I wouldn't put one behind a big block, but a '63 Muncie with the smaller shaft and bearings would be (and obviously still is) just fine behind a healthy small block. Guys (like me) were mainly breaking these transmissions with big-blocks and sticky tires. With a 250-375 HP small block and the skinny tires that fit on our cars, you'd have to work at blowing one of these up, IMO. The last early Muncie I blew up was in a '65 GTO power-shifting into second gear with the tripower to the floor. That didn't end well.....and that was 35 years ago.

DZAUTO

A lot of good info above.
One thing not clarified----------------Bell housing. If I remember, ALL 69 bell housings were the larger 3889621 version (commonly referred to as a 621 housing). So, if you use the 69 Muncie, and, if in fact the 69 housing is the 621, THEN IT WILL BE NECESSARY TO ALSO USE THE LARGER 69 FLYWHEEL-------------AND STARTER! No need to do that!
The 63-ONLY bell housing (with the smaller hole) will be a 421 and 64-later SMALL housings will be a 383 or 403 version. Soooooooooooo, if you want to use the 69 Muncie, but retain the existing small flywheel, you will need to round up a 383 or 403 housing (the 383 was one year only and the 403 housings are VERY common------------and cheap).
No need to worry about the throwout bearing fork. Your 63 fork will snap right onto the ball stud in ANY bell housing. The geometry is the same for all of them.
As shown in the above pictures, the change in shifter shafts and the slot in shifter levers changed from 68 to 69. The 63-68 shift levers have the smaller slot and attached to a threaded stud on the side cover. In 69, the levers got a longer slot and were attached with bolts. TOOOOOOOOOOOOOO EASY to change. Simply swap the 63 side cover onto the 69 Muncie and use all the 63 shifter parts. OR, if a Hurst is installed, just swap the side covers and order a Hurst for a 63.
Last, as everyone has said, the 69 Muncie is the better tranny, and with a quick swap of side covers and changing to a 403 housing, EVERYTHING, EVERYTHING, EVERYTHING will fit together perfectly!

gleninsandiego

A huge thank you for all of the above

After doing more research, another possibility arises

I have the everything from the Z bar back from the 69
So it appears I can use the 69 Z bar, linkage, flywheel, clutch, bell housing, Muncie and shifter
I have to order a bracket that holds the shifter to the trans as the 69 bracket attaches to the crossmember
The result of all of this is the 69 shifter will sit an inch higher.

Obviously it won't look like a 63 shifter but it will all be reversible in the future

domenic tallarita

Don't know if it was mentioned, but the 63 in the pic does not have the spedo drive on the drivers side.

Dom

DZAUTO

You are exactly correct!!!!
I failed to point this out!