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I stopped by a local Chevy dealer's parts store looking for 1/2" fine thread flywheel bolts for my 292. He says that he can order them; doesn't stock 'em. He also said that if I didn't want to wait that I could try a local hardware store (like Ace).

I wouldn't think that the bolts Ace hard would be nearly strong enough to hold the flywheel in place securely. I think I'd be too scared of breakage to drive it. Has anyone else ever used hardware store bolts on the flywheel? I have three OEM bolts now and need three more.

Oh yeah, this is the heavy duty (manual shift) flywheel that has the clutch disk and pressure plate bolted to it; not the lightweight one.

-ftyler

You should be able to get grade 8 bolts at a good hardware store. Be careful of the head style I'm not sure if a socket head will fit.

One more thing to worry about: The bolt heads must clear the clutch disc. I think the flywheel bolts have 'thinner' heads so they don't stick out into the disc with clutch applied.

Correct, these aren't off-the-shelf grade 8 bolts. Order the right ones from the dealer.

-Boyo

Boyo's right. And replace all the bolts. when you put in the new ones, be sure the holes are clean and use red loctite.

Guys while I have you here...

Another problem. My flywheel and the one I purchased from the salvage yard appear to have 7/16" holes but the crank holes on the 292 have 1/2" holes. What are some good sources for 1/2" standard flywheels? I'm guessing that it would have to be an 80s model heavy duty pickup.

Would it be possible to have a machine shop just re-tap the holes to 1/2", fine thread?

-ftyler

Pontiacs use 1/2 flywheel bolts, maybe you take a ride to your local speed shop or search Summit racing or Jegs online.Maybe they are the right length.The machine shop can easily drill out the holes to 1/2 inch and the flywheel isn't tapped.Don't you just love all the last minute problems?Means you're getting close to finished.

Tell me about it!

-ftyler

Flywheel bolts I have bought are all shallow height heads. My last problem was finding right length and then no one has lock strips now. I was told to use inner star washers on them and Locktite Red. I did that, and still holding after two years. Expect to pay about $2 or more for each bolt! I once did a Jeep 4 cylinder that book said to buy new ones and they wanted $8 a peice at dealer! What's with that? $40 dollars or more for set? They say old ones stretch when torked, and can't reuse. I've re-used them for years on everything else I built. I DiD re-use the Jeep ones and used locktight on them.
I wouldn't use the "Hardware store" type myself, but whatever. On the flywheel...don't 292's have own type as balanced diff and diff bolt pattern than 250's had? Maybe that's whay diff holes size, so you don't mix up? You could drill the smaller holes out on flywheel to match 1/2" holes in crank maybe, I wouldn't bore or redrill the crank if mine. Would have to be apart for that anyway. I would modify flywheel or find right one for your crank. Better check with Inliners site to see if they interchange. Would think they should know. Or, maybe Clifford's shoud be able to help. They do only small engines.

points WELL taken GLPerry.

I'm ordering 6 new flywheel bolts from a local Chevy dealership today or tomorrow.

Guess what? My crankshaft has 3 "dowel" holes and the flywheel has only one. Can this flywheel still work on the crank?

Maybe, Probably not, and No. My bet is no. You likely have the wrong flywheel.

Please don't drill out the square hole so the round peg will fit! (Like, an analogy and stuff)

Chip

A look at the GM parts book shows early 292's shared a common flywheel with the 230-250 6's and the 283-327 small blocks.These engines are internally balanced so the flywheel is not part of the balance factor as on some engines.The later 292's have 3 dowel holes and 1/2 inch bolts.You can have a competent machinist modify your existing flwheel just as hot rodders have always done or search around for the factory wheel.The old parts book says something about reaming the dowel holes on new replacement 3 dowel flywheels after bolting it to the crank shaft.Perhaps a flywheel from one 3 dowel 292 may not fit on another 3 dowel 292.

But is the later 292 internally or externally balanced? I'd hate for his new engine to shake apart cuz it isn't balanced right.

Chip

The 292 I have here is the older style, no help, the reference books don't mention any balancing changes, so you gotta say its all the same differences,lol.If not, ftyler can hire out his truck as a paint shaker.

I've got no knowledge about your particular application, ftyler, but PLEASE be careful and check that you have the right flywheel. This comes from personal experience, replacing blown-up 3.8 V-6 in 1995 Windstar. Our lovely F**d reman company sent me a reman from a 2000 Windstar...with no flywheel. Of course, the newer engine was INTERNALLY balanced, while the original was EXTERNALLY balanced. Shook like CRAZY when I put it together and had all the more experienced techs in the shop scratching their heads guessing what was wrong. Had to pull the transaxle out the next week when F**d finally sent the right flywheel. Could one of you guys maybe help him I.D. with casting numbers or something so's he's not guessing? Having to do a big job like this over again can turn a hobby into "work" in one BIG hurry! Best of luck, ftyler.

Regards,
Wannabe

Santucci's 292 performance book makes absolutely no mention of anything unusual. In fact it mentions all the crankshafts are interchangable and balanced exactly the same.The best part of all Chevy sixes is the interchangability of parts.

Question for Tony. I have 2 292's one a 73-84 model, the other a 75-84 model (according to casting #'s), one has a TH350 bolted to it and the other an SM465 4spd. My question is, I need to swap transmissions (switch SM465 to good 292) are the flywheels interchangeable since the cranks are supposed to be identical? Does Santucci's manual address the flywheel issue? Thanks for any help!

Santucci mentions drilling out the 7/16" old flywheels to accomodate the 1/2" bolts in later cranks. He also mentions that some drill out all the dowels and tap the holes for a total of 9 flywheel bolts if you are running a 4spd, but if you are running an automatic, you can leave it stock without worrying about shearing anything off. Apparently some racers experience problems when cranking 500 - 600 HP through only 6 bolts and a couple of little dowel pins when grabbing gears on the drag strip Santucci also mentions that crank balance should always be "zero".

I know a guy "Walt Skoczylas" that I have worked with who has a methanol fueled 292 w/6-71 blower who does ~8 second quarter miles. He claims the crank shaft is the last thing to worry about as far as these motors are concerned.

eal424x4 ,
Leo Santucci's book doesn't mention flywheels. Since the crank balance is the same, the flywheels are interchangable.For mildly built street engines or a stocker, the flywheel is not a big issue so long as it fits on properly.Leo's book is primarily addresses modified engines, where high rpm crankshaft harmonics are a problem.

Tony . . . Santucci doesn't mention flywheels? I guess that he doesn't talk about flywheels directly, he does talk about crankshaft flange prep for various types of flywheels. Page 27 provides a guide for prepping flange for drilling and tapping to larger holes and replacing dowels with bolts. He also addresses this same information on page 45 and shows hardened plate for use with aluminum flywheels, torque specs, use of loctite, need for different prep for automatic vs. clutch, etc. My brain made the jump to thinking he was talking about flywheels as I have used this info to figure out what to do with my flexplate.

Guys,

So does this mean that I'm absolutely safe moving forward with drilling out the 7/16" holes to 1/2" holes on the flywheel I plan on having resurfaced?

If the answer is yes, then another question for Tony - do I need to move forward with drilling out two additional dowel holes in the flywheel to match the crank?

Nobody has mentioned the other critical measurements of the flywheel. Are all 292 flywheels the same OD?
Will they all accept the same clutch setups & bolt patterns?
Do they all use the same ring gears?
Any differance in flywheel thickness or weight?
Do they have to be installed a particular way in reference to the crank, ala 235?

What tranny is Ftyler using again?

Just trying to get it right
Chip

GM four speed manual overdrive (89MM, or whatever they call it). It's a light duty 4 speed tranny used in GM's full sized pickups in the mid 1980s (I believe it was made by Dodge for GM).

Should work like any other GM (Saginaw, Muncie, T10, T5, etc.) tranny. Mine uses the very typical standard GM v8 bellhousing.

Ken,hmmm, flywheel prep yes , as in how the flywheel bolts to the crank.But no info on flywheels for standard trans at all.No weights, sizes, recomendations for aluminum or steel wheels etc.Your brain will have to fast foward to another source if you need info on stick flywheels.
Fred, I would drill the flywheel if I couldn't find a replacememnt thats fits.I would also drill the dowel holes. The drilling must be done accurately using proper machinery.Of course what I may do and what you may do on your engine may be completely different.If you are uncomfortabe about this, seek additonal advice from some one who has actually been there before.Email Sixpack here on Stovebolt,he may find the solution for you.

If I'm following this thread correctly it sounds like best solution would be to find the right flywheel. Enlarging the bolt holes from 7/16" to 1/2" and installing dowels to match the crank is machine shop work, and many engine shops aren't even equipped to do this - You may need to go to a shop that works on big farm or road equipment. And they will probabably want you to bring in the crank too. The dowels have to be sized correctly because they are an interference fit to help keep the flywheel from loosening.

It might be worth a call to Precision Engine Service in Waxhaw NC (704) 843-5477 for help in locating a flywheel. These guys still do a lot of late inline engine work and have many sources for a lot of stuff. E-mail me off-list and I can maybe send you some other contacts closer to you.

FOLLOW UP TO THIS THREAD:

Guys:

Found the exact factory match flywheel. Half inch bolt holes, 3 dowel pin holes and all. Supposedly unused NOS off Ebay.

Ended up spending a pretty good sum of money after getting the owner to sell outright, shipping and cost of resurfacing. But still well less than half the 308.00+ tax GM wanted for a new one. Best of all, my new 11" Luk clutch set bolts up perfectly.

Good ending! Everybody wins!