Switching to a 4-speed and looking for some input on the High Performance Clutches out there. Engine is a 454 with LS-7 heads, .638 lift cam, (3000 to 7400 RPM) LS-6 Pistons, etc. Also my flywheel has 3973457 on it. Is that for a 454? Is an aftermarket flywheel worth it?

Centerforce Dual Friction. Fantastic! I run it behind my 400+ HP 383. Beats stock hands down.

I cannot find that number in anything I have. The GM part number is 3993827. This is a 14 inch flywheel for an externally balanced 454 and will take an 11 inch clutch. This is the flywheel I have on my LS7. There will likely be some other opinions for performance clutches, but my recommendation is Centerforce Dual Friction, 11 inch with that kind of power. Low peddle pressure and it works great. Check out Jegs or Summit for aftermarket flywheels. For street use and an occasional (read almost weekly during the season) flog at the drag strip the GM part will still probably do just fine.

Have A Great Elky Day
Mike

Not in any book I have either, supposed to be out of a car. Surely SOMEBODY knows what this is.

JKENNEDY, Well i guess if i were you id check and see if the flywheel is for a 454. (does it have the counter balance weight on the inside?). As long as its for a 454 and its 11" i would use it. I have used stock units before with no problems. As for the clutch......CENTERFORCE ALL THE WAY!!!. Ive used these allot and they take a beating and enjoy it in the process! With the LS6 i would go with the dual friction like everyone else mentioned. Sounds like a good combo!. Mine is almost the same and my chevelle runs 12.11 @116. With allot of wheelspin. So get that clutch in there and go out and have some fun tearing up your tires.

Well at least I know which clutch to buy. Now if I just knew which flywheel I have. Thanks for everybody's help. I appreciate it.

Yes, I too would recommend the Centerforce Clutch. I have a Centerforce Gold right now and this thing holds up great. I bought this before the dual friction series was out. I used to go through a high performance 3 finger type pressure plate every 6 months (they would break springs) and the pedal pressure would break my clutch linkage every few months. I was very skepical of this Centerforce diaphram clutch with weights on it, but it has been in for over 5 years with a nitrous fed weekly abused big block without any problems.

I'm just about to order my first Centerforce Dual-Friction in the next week or so - can't wait to get the motor back together!! I've got Chevelle BB withdrawal so bad now I've got the shakes !!

------------------
Stan Hanek
'70 SS - 396 4 sp.
haneks@wdni.com

Hello, Did you ever find out about the flywheel part # 3973457? I have the same flywheel and a vibration to go with it.

I have a Zoom kevlar kit in my 65. So far, so good.

Has anyone used flywheel part#3973457 behind there 454? Thanks ART.

If you're going to be doing any racing, or just as a good safety measure, I would seriously consider a steel flywheel and scatter shield instead of a stock cast iron wheel and aluminum bell housing. I dont think any track will let you run a stick car without one.

Mcleod 12" made to fit the 11" GM bolt pattern.

Switching to a 4-speed and looking for some input on the High Performance Clutches out there. Engine is a 454 with LS-7 heads, .638 lift cam, (3000 to 7400 RPM) LS-6 Pistons, etc. Also my flywheel has 3973457 on it. Is that for a 454? Is an aftermarket flywheel worth it? Of all the pieces you can replace the flywheel is MOST important driveline part you must have. I have seen flywheels explode on two different occasions and neither was a pretty sight. Nothing in the driveline will do more damage when it lets go. Anyone who uses a cast iron flywheel should have a mental evaluation. You might get by with using one for a short while but when you put on some good biting tires it will heat crack and BOOM, it'll let go. My friends turned loose at 7500 RPM and destroyed every piece from the radiator to the rear end. Engine, headers, distributor, scattershield, clutch & flywheel, transmission, shifter and driveshaft all gone in a matter of a couple of seconds. He was lucky though because he could have lost his feet or legs too. Get an aftermarket steel flywheel as that is one piece that will last almost from now on.

Man, this thread is an old one! :eek:

Man, this thread is an old one! :eek: It is old but you only get one set of legs and feet.

Mcleod 12" made to fit the 11" GM bolt pattern.
Best one around! I second that vote.

Switching to a 4-speed and looking for some input on the High Performance Clutches out there. Engine is a 454 with LS-7 heads, .638 lift cam, (3000 to 7400 RPM) LS-6 Pistons, etc. Also my flywheel has 3973457 on it. Is that for a 454? Is an aftermarket flywheel worth it?

Yes after market flywheel is worth it. I think it is the best way. I think it is 454. I have experienced the same thing. :yes: