I've been doing a little cleaning before winter is here and I came across this flywheel. The problem is that I have no idea what it fits. It weighs about 34 lbs and is just a tiny bit over 14" in diameter. If I counted correctly, there are 168 teeth. Measuring between the 2 furthest crank bolts is 3 5/8" on centers. There are no identifying marks that I can find. I am wondering if it is possibly an old aftermarket piece for a SBC/BBC? Does anybody have any other ideas?
Is there something unique about that particular hole location/arrangement? I've seen similar indexing holes on Chevys and Pontiac OHC6 and the indexing holes look the same to me. Just wondering if there is a measurement or something I could check to confirm or rule out this possibility?
Appears to be a neutral balance so I have to wonder about the index hole. The 34 lbs suggests a larger displacement. Also the bolt pattern for the clutch appears to be for a large size clutch. My guess is a Kia............. Seriously though, I'd measure the id of the the crankshaft hole. I think the different manufacturers had different diameters on the thru hole, so getting that info might help.
I have an old chart that shows early 55-76 Chevy internal balance (two piece main seal) had 168 teeth . 14.096 OD 70-76 400 and 454 large bellhousing 168 teeth but external balance 14.096 OD 63-76 400 and 454 small bellhousing 153 teeth 12.835 OD 55-63 All 6 cylinders (except Corvair) 168 teeth 14.096 OD I have a Chevy tech book that shows the internal balance flywheels with the extra hole in the bolt pattern
Looks like an aftermarket with a dual pressure plate bolt pattern. Does it ring like a bell? Kinda looks like and small block big block chevy to me.
Sure does. With the tooth count and the diameter I was betting it was Chevrolet. But, I have certainly been wrong before.
Cast irons have machine mounting bosses on the back. Aftermarket steel of some kind. Appears to have Long and Borg and Beck patterns, very typical of some aftermarket companies. Not much depth to the mounting area meaning to me a springless disc or automatic cap screws. Are the holes for 1/2” or 7/16” cap screws? Dip it in vinegar and it will come out like new.
I checked a Chevy register diameter and it is 2.484. Yes, that flywheel is drilled for two different pressure plates but both are Borg & Beck.
The bolt holes for the clutch are 3/8" as near as I can tell. If it is of any consequence, the crank bolt holes appear to be 7/16" I've heard that suggestion about vinegar a few times in the past... although I haven't yet tried it(I think vinegar is probably the nastiest smell on the planet).
I’m guessing you or your wife doesn’t read hints from Heliwes (sp) and if your dishwasher is stainless steel it’s not spotless. That stuff works
The smallblock Chevy I have checks 2.487 with an intrimic........... Measure (tape measure) 12" inside the ring gear and 13" outside the ring gear and has the extra hole in it.
In this case I don't think its a matter of extreme accuracy that matters. There are variations in flywheels as well as the tools available to check them. Anything close to our measurements is most likely going to identify it as being for a smallblock. I'm kinda interested in what the dimensions are on some other flywheels. I'm going to build at least one, and maybe another couple 500 Cads. Manual flywheels are available new but are pricy. I did find a new one from a guy for $300 but from dealers they are higher. It looks to me that Pontiac and Olds have the same OD and tooth count....and you can actually find used ones. I'm thinking about buying some when I find them and boring them out to fit a Cad (3.000). There appears to be plenty of room for an additional bolt pattern. It depends on how much room there is diametrically to bore it out without hitting the existing bolt pattern. Anybody got any old Pontiac or Olds flywheels laying around?
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