1987 clutch and flywheel sizing

[kipps]

I have a 1987 V20 pickup with a stock 350 TBI and SM465 transmission. I tore the teeth off the flywheel due to a bad and poorly aligned starter. I'm replacing the flywheel, clutch and all other related components while I'm in there. A friend highly recommended I use a OE Ram clutch instead of buying from the auto parts store, citing much better quality for similar price.

I ordered Summit #RAM-88793, which is listed as a 12" clutch kit. I realized afterward that the stock clutch was 11.85". Will the 12" Ram clutch fit onto a stock replacement flywheel, or is 12" fundamentally different from 11.85"?

Also, is there any reason to doubt the quality of a $80 flywheel from an auto parts store?

Please, someone tell me I'm overthinking this, so I can just pick up a flywheel, and be ready to assemble the truck when the clutch arrives. I need to get that thing back into use.

[Marshy]

Since you're going to buy a flywheel why not just get one 12" to match the clutch size, will the starter not fit? I know very little about clutch selection, only know how they operate.

[crazy longhorn]

Kipps, check your bolt pattern, to be sure, but on the older trucks, you could bolt an 11" or 12" clutch, on the same flywheel...(the 12 is actually 11.85), & the hat is scalloped to fit the bolts. If you are racing/hy revs, you could spend for a billet flywheel.....but not needed in a stock or mild street app. I used a cast Sachs flywheel on my 5.3, & have no issues with engine balance? For my use, the 69 is a cruiser (may see 5500, from time to time)....I see no issues with the autoparts flywheel Longhorn

[kipps]

Thanks for the replies! I guess my hesitation is that the clutch listing describes the disc as 12.000 inches, and I'm worried that disc might not fit onto the stock-size(11.85) flywheel.

http://www.summitracing.com/parts/ram-88793

The reason for not ordering a 12" flywheel, is when I narrowed down the search on summit for that size, I got 1 option that cost multi-hundreds. So if there's a chance a stock size one will work, I'll check into that first.

This is a completely stock situation, so a cheap heavy flywheel will be just fine.

About the truck, in case anybody's interested -- I spent several years struggling with a 73' ford and a 81' ford, till the 73 got parked because it's 2wd(it has a bit of family history, so it won't get junked, but I think I have a specialized use for it in the near future), and the 81' is parked and awaiting scrapping because it was shot in about every way possible. After learning all the difficulties with Fords, I figured the grass must be greener on the other side of the fence, so I bought into a whole new set of problems with this Chevy. I bought it 3 years ago, and by the time this new bout of repairs is over, I'll have replaced front wheel bearings, all u-joints, t-case seals, clutch, flywheel, starter, water pump, motor mounts, drag link, power steering pump, clutch line, ball joints, tires, driver's door glass and window channel, and rear glass. I figure(as I have for the last 2.5 years), that I'm one fix away from bulletproof. It's a farmin' square, (dairy farmin' that is), and I'm rather proud of the redneck look. It has 33x12.5 tires, but otherwise is stock.

[Marshy]

Nice load, here's some black cherry firewood from last year.


Do you have stock K10 suspension? Any issues with fitting the 33-12.5 tires, do they rub in the front? I would like to get 33's next or 35 but most are 12.5 and I'll need wider rims too and fear them rubbing. BTW, I don't want to tell you all that Ive done to this truck.

[kwmech]

You don't have to replace the whole flywheel just because the ring gear is stripped teeth, you can buy just the gear. I've never seen a 12'' clutch that actually measured at 12'', even the factory 12'' 454 disc measures in a 11-7/8''

[kipps]

The cost and hassle of replacing a ring gear and resurfacing the flywheel tipped the balance strongly toward just replacing the whole thing. My mechanic brother took one look at my flywheel when I got it off, and laughed. He said someone had clearly replaced the clutch and pressure plate before, but had not touched the flywheel. He pointed out all the blueing and cracks on the flywheel, and said a PO must have been slipping the thing pretty bad.

Thanks for everyone's responses on this. It turns out my fears of incompatibility were ungrounded. The new clutch arrived today, 48 hours after I ordered it on ground shipping(kudos to Summit and UPS!). The new disc is exactly the same size as the old one-- 11.85". Unfortunately, I neglected to order a clutch fork in the same shipment, since mine was nearly rusted out and missing several clips. Now I have to wait till it arrives next week at the auto-parts store.

[kipps]

Originally Posted by Marshy

Do you have stock K10 suspension? Any issues with fitting the 33-12.5 tires, do they rub in the front? I would like to get 33's next or 35 but most are 12.5 and I'll need wider rims too and fear them rubbing. BTW, I don't want to tell you all that Ive done to this truck.

I'm nearly certain that my truck has no suspension or body mount mods. It is a 3/4 ton truck, but I doubt that makes any difference in clearance. The 33x12.5's don't rub at all, and I'd venture a guess that 35's would clear without modifications. Don't take my word for it, though.

I have 16.5 x 9.75 rims on my truck, and the two new tires I bought a year ago cost $250 apiece. I'm considering buying several new 16 x 10 rims before buying any more new tires, since the difference in price between 16.5" tires and 16" tires is nearly the same as the cost of new rims. I wouldn't be money ahead now, but since I plan to keep the truck for quite awhile, I'd significantly benefit on the next set of tires.

The rims I'm drooling over are Wheel Vintiques Series 82 rims(google that). With a rattle-can coat of primer gray on them, they'd fit right in with the redneck theme. I'd much rather find cheap used rims in the same size and style, but I haven't had any luck so far.