Question About Flywheels

[gmc67swb]

I've Been Running The Stock Straight 6 Flywheel And 10.4" Clutch In My Truck But With A V-8. The Flywheel Has A Step Down On It. I'm Curious If I Can Go To A Bigger Flywheel And Run An 11" Clutch With Out Changing My Current Bellhousing/starter Configuration? The Reason I Mentioned The Step Down On The Flywheel Is Because It Increases The Diameter Of The Flywheel And Looks Like It's Not Used. Thanks In Advance Guys.

[passthebuck]

i belive that the flywheel diameter is the same for a 10" & 11" clutch BUT the bolt pattern on the pressureplate is different for the two clutch diameters. If my memory serves, you must get a flywheel made for an 11" flywheel. Incedentally, I JUST put a new clutch in my truck & the guy asked if for 15 bucks more would I want a 12" clutch? I though if 11 is good them 12 is gotta be better right? He said that the flywheel is the same for 11 & 12 clutches. My pressureplate for my 11" was toast so I got the friction disc, the pressureplate & throwout bearing for 175CDN. just my opinion but if ya gotta get a new pressureplate, think about making the jump to a 12" disc.

[gmc67swb]

Ttt

[crazy longhorn]

Yes, that is right on info.....the ring gear is the same on the flywheels(168tooth), for 10.4, or 11". If you are running a 250 L6, you can bolt the pcs on the back of a sb (anything but a 400 sb)...external balance on the wheel for that puppy. The 292 flywheel will not work on the back of a sb however. the 11 & 12 " clutches do use the same bolt pattern, but the good (hypo clutches ) , are 11 ". I run a centerforce dual friction setup on my longhorn.....they arent cheap, but you get what you pay for If you are planning hard use, off road or racing....or even "spirited" street driving, I just cant say enough about the Centerforce clutches. they rock! crazyL

[Brainchild]

I was sure that there was a different flywheel ,at least some that were smaller in dia.Some use the starter with the 2 long bolts=11-12 inch,and the long and short bolt style starter=10.Most of the trucks this year that I have worked on had the starter that bolts to the bellhousing with 3 bolts.

Is this long short style starter just for the automatics? I was sure that there was a standard that used it also

[passthebuck]

both my 67's are 3sp manual & they both bolt the starter to the bellhousing. Any auto trans setup I've seen (BB, SB or L6) bolts the starter to the block with two long bolts vertical & you can use either a big or small flexplate with the right starter nose. Now the 2 GMC's I have are the first manuals I've owned & they both use 3 short bolts horizontally to the bellhousing & the flywheels are 168 teeth. crazyL: I was looking at the partsbook & the 12"er is used all the time behind all the modern GM diesels. Is my 12" not capable? I just though that those turbo diesels make mega torque & the 12"er could take it cause it had sooo mycxh more surface area... hmmm. Am I in trouble?