60 Corvette & 71 GMC clutch, bellhousing...

[Greg L.]

I should know this answer from all the help I've received here on my stiff clutch issues in my 60 but before I commit myself I need to know for sure...

Will the bellhousing, flywheel, starter etc from a 71 GMC or Chev 1/2 ton 6 cyl fit and function properly in my 60 Corvette?

If I understand what other have said correctly I think it will but I'd like some confirmation on that before I go to all the trouble of removing the truck parts. I know the bellhousing won't look 100% correct with the mounts pads but if that is the only issue then I'll run back to the wrecker and grab these parts while I can. This way I can get it working properly and worry about getting the proper 60 only aluminum bellhousing later.

[Bill M.]

Re: 60 Corvette & 71 GMC clutch, bellhousing...

Greg:

I'm not sure, but make sure the bellhousing has the 2-bolt mount on the driver's side for the cross-shaft bracket. Some trucks don't have that mount.

Bill

[William C.]

Re: 60 Corvette & 71 GMC clutch, bellhousing...

what is the casting number on the truck BH you are looking at?

[Greg L.]

Re: 60 Corvette & 71 GMC clutch, bellhousing...

Sorry guys but I didn't think to get the casting number. I also didn't notice if it has the two-bolt mount for the cross shaft bracket. Guess I should have looked closer for both.

I wonder if there is a casting list some place of bell housings that will work in the 60 corvette one?

[William C.]

Re: 60 Corvette & 71 GMC clutch, bellhousing...

I have an old "Hollanders that says the following will interchange: 60m Corvette, 60 chev with 348 engine, also 61-62 Chev with 348 409 engines, as previously mentioned. I don't believe any of the cast iron truck housings have the clutch shaft mount provision.

[Greg L.]

Re: 60 Corvette & 71 GMC clutch, bellhousing...

Thanks Bill.

Since you have a Hollander's would you mind looking up to see what other applications used the same flywheel, fork, bell housing bottom cover and starter as my 60? Looks like I might as well just pony-up and get the right bell housing, or at least an earlier cast iron version.

Thanks.

[William C.]

Re: 60 Corvette & 71 GMC clutch, bellhousing...

60 chevy with 348, only other application excepting Corvette

[Tom P.]

Re: 60 Corvette & 71 GMC clutch, bellhousing...

ANY and ALL Chevrolet based V8 engines, and 6cyl Chevy engines beginning with the 63 model, as well as the respective flywheels, will physically bolt up to ANY Chevy based bell housing (many GMC trucks commonly used Chevy V8 engines).
If you are planning to go with a bell housing that uses a housing mount starter, then any open bottom (alum or iron) housing, beginning with a 55 model will work. The open bottom housing will MANDATE a 14in diameter, 168 teeth flywheel. YOU CANNOT USE THE SMALLER, 153 TEETH FLYWHEEL WITH A BELL HOUSING MOUNTED STARTER!!! If you will be using the stock style clutch linkage, then as already mentioned, you will need ANY bell housing that has the boss with 2 holes for mounting the cross shaft (Z-bar) bracket.
The main thing that will be mandatory is the throwout bearing fork. It must be a fork that is specific to the Corvette clutch linkage.
The 55-62 Corvettes DID NOT utilize any kind of mounts on the bell housing. Thus, it DOES NOT matter if the housing came from a car or truck----------------as long as it has the boss/holes for the cross shaft bracket.
If you go with a 63-later style fully enclosed bell housing, there are two choices, small (403 style) and big (621 style). Again, you will need to use the correct Corvette style fork, the housing will also need to have the boss/holes for the bracket and a BLOCK MOUNTED style starter will be required. BUUUUUUUUUUUUUUUT, many EARLY blocks DID NOT have the required holes on the pad for attachment of a block mounted starter.

In my opinion, the simplest and easiest way to start out (and certainly cheapest) is to round up a 57-62 pass car cast iron bell housing. It will fit and function correctly and they are dirt cheap at swap meets. The larger, 14in diameter, 168 teeth flywheels that have a bolt pattern for an 11in clutch are also plentiful and cheap. This would get you going and IF, IF, IF, at a later date, you should run across a 60 alum housing (take a 61-62 housing if one should become available) at an affordable price, then it would be fairly simple to swap the alum housing for the iron housing.

[Tom P.]

Re: 60 Corvette & 71 GMC clutch, bellhousing...

Ok, I rounded up a selection of bell housings and took a picture of the side where the boss is (or needs to be) for the clutch cross shaft bracket should be attached.
I'll identify what each is, but to keep it simple, it appears that ONLY open bottom (iron and alum) pass car housings have the necessary, correct boss with two threaded holes.
First, the housing on the lower left is the 64-later full enclosure, 403 style which only fits the smaller, 153 teeth flywheels and requires a block mounted starter with a straight across bolt pattern. It has a single hole, in the forward position only, at the same location of the forward hole of a pass car housing with the required two holes.
The second housing (on top of the 403 housing) is the larger, full enclosure, 66-later 621 style (as well as the 444 and 697 style) that is used with a big, 168 teeth flywheel and requires a starter with a CAST IRON, staggered bolt pattern nose.
The housing on top of the 621 style is the early-70s-later full enclosure truck housing (notice the additional bulge on the lower part of the housing). It has the boss on the side, same as the boss on the pass car housing, but with only the rear hole. I'm sure a forward hole could be drilled and tapped.
The (rusty) housing in the center is the mid-50s thru early 70s style truck housing. It has NO BOSS at all, thus, it won't work if a boss is required for attachment of a bracket.
The housing next to the far right is the 55-62 style iron housing used on pass cars (-59 on Vettes). As can be seen, it is the only housing with the required boss with holes for attachment of the bracket.
The housing on the far right is the 61-62 alum housing, with a boss, which was used on 61-63 348-409 pass cars and ALL 61-62 Vettes.
There was NO 168 teeth flywheel/large housing used on ANY 63-65 Vettes (including the 65 396 Vettes).


This is the BIG, full enclosure bell housing used ONLY on 64-65 pass cars (full size pass cars with BB and Z16 65 Chevelles). As can be seen, it's a considerably different housing----------------RARE/EXPENSIVE!
As you see, it has the same type of single hole boss as the later full enclosure car housings.

[Greg L.]

Re: 60 Corvette & 71 GMC clutch, bellhousing...

Well that helps a bit. I'll look for the obvious two bolt boss when I go back.

Even though the Hollander says these parts won't interchange with anything other than 60 Corvette and 60-62 full size car with BB I wonder what the real difference is? I can see the 6 cyl starter and flywheel being "different" but it might be as simple a mod as to replace the field housing with a 8 cyl one and rebalance the flywheel, if that. Even as far as the mount boss goes I guess I could just still used the block mount that it already being used. The whole point of my quest here though is to try and get the clutch to work as advertised so unless I change it all I might not be any farther ahead than I am now.

I know the 60 and C2 cross shafts are different but will one fit in place of the other? Maybe just swapping out the C2 shaft that's there now with a proper 60 shaft will help a lot seeing as it has it has more leverage.

[William C.]

Re: 60 Corvette & 71 GMC clutch, bellhousing...

I believe the 6 cyl has a different bolt pattern on the block. The only difference between the 60 and 61-62 aluminum housings is the opening for the clutch fork is larger on the later models, otherwise identical.

[Tom P.]

Re: 60 Corvette & 71 GMC clutch, bellhousing...

Well that helps a bit. I'll look for the obvious two bolt boss when I go back.

Even though the Hollander says these parts won't interchange with anything other than 60 Corvette and 60-62 full size car with BB I wonder what the real difference is? I can see the 6 cyl starter and flywheel being "different" but it might be as simple a mod as to replace the field housing with a 8 cyl one and rebalance the flywheel, if that. Even as far as the mount boss goes I guess I could just still used the block mount that it already being used. The whole point of my quest here though is to try and get the clutch to work as advertised so unless I change it all I might not be any farther ahead than I am now.

I know the 60 and C2 cross shafts are different but will one fit in place of the other? Maybe just swapping out the C2 shaft that's there now with a proper 60 shaft will help a lot seeing as it has it has more leverage.

Greg,
ALLLLLLLLLLLLLLLLLLLL the pass car and Vette cast iron bell housings (open bottom) and the 60-63 alum open bottom bell housings will 100% bolt up to, fit, function and be compatable with your 60 Vette.
Look at the 2 bell housings below.
The iron housing is a 55-57 pass car and 55-59 Vette style (that particular housing is a 57). Notice the angled flats on each side. Those were ONLY, ONLY, ONLY used on 55-57 pass cars for the rear engine mounting. In 58, ALLLLLLLLLL pass cars went to a rear tranny mount sort of similar to the 55-later Vettes.
The alum housing is a 60-63 style (60-62 on Vettes). Notice that the alum housing DOES NOT have the angled flats for engine mounting. The cast iron bell housings for 58-62 PASS CARS looks just like the 60-63 alum housing.
Thus, ANY 55-62 pass car, open bottom, cast iron bell housing will fit and function just fine on your 60 Vette. Additionally, even though the 55-56 housing will fit/function, the bolt holes for the starter mounting on 55-56 are all threaded and ONE hole in the 57-62 housings is not. Thus, if you locate a 55-6 iron housing, it will be necessary to drill the threads out of one hole. No biggie.
NO, it won't be correct!!!!!!!!!! BUT, it WILL function----------------substantially cheaper than an alum version-------------and get you going until you can locate a 60 ONLY alum housing (good luck at that) for an acceptable price (good luck at that also). Again, as I said above, if you should come across a 61-63 open bottom alum housing for a decent price, get it, even though the ONLY difference from a 60 housing is the size of the opening for the clutch fork!

[Greg L.]

Re: 60 Corvette & 71 GMC clutch, bellhousing...

Thanks again guys. I "get" what will work now in terms of a period correct bell housing(saved all the pics for reference too) but I what I really would like to know is if I can grab a bell housing, flywheel, starter, etc out of a late 60s-early 70 Chev truck.

The reason I am all hung up on that is because swap meets up here are few and poor at best and I don't really wanzt to grab a part here and a part there and hope they all come together some weekend under the car. Nor do I want to lug a flywheel or bell housing around a swap meet in Carlisle or Pomona, pack it to ship or fly back with me and then find that it's wrong.

This is why the set-up from this 71 is so enticing. It's all there and can be had for about $90. If the bell housing has those mount holes then good. If not then I'd like to at least get the rest of it and just pry my wallet open and maybe even get the right bell housing right off the bat. The key to all this is first knowing what, if any, of the clutch parts will fit from these still common chevy trucks.

[William C.]

Re: 60 Corvette & 71 GMC clutch, bellhousing...

I believe you will find that the '6 cyl truck BH does not have the clutch linkage provisions. Nor does the truck 6 cyl flywheel interchange with a V-8 flywheel, not what you want to hear, but you would be even more unhappy if you bought a bunch of heavy parts and got them home only to find they don't fit at all, no mater how inexpensive the adventure. The NCRS Driveline, Hemmings online, eBay and similar resources should with a little patience yield good results in locating a setup that will work from what you have learned here, and the 55-57 Chevy iron bellhousings are relatively plentiful and inexpensive.

[Greg L.]

Re: 60 Corvette & 71 GMC clutch, bellhousing...

Yes you're right Bill "not what you want to hear, but you would be even more unhappy if you bought a bunch of heavy parts and got them home only to find they don't fit at all".

I'll try and source the parts elsewhere as well as keep an eye out for an 8 cyl version to see if it will be a better prospect.

Right now I'm really glad that I kept all my old Drivelines!