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Author Topic:   Shaving a flywheel and adding a clutch.
Speed Racer X
Dirt Full Roller

Total posts: 61
posted November 24, 2002 10:13 PM
We are planning on usin a flywheel off a 250 Chevy 6 cylinder on on our 350. It has a 10 inch "flat diaphram" presure plate and clutch disk and the flywheel weighs about 28 lbs. Without building a time-bomb, how much can we shave off the flywheel?? Will the 10" clutch hold up in a 3400 lb car with a 6500 RPM, 12.1 compression 350??? Thanks!!!

Eljojo
Dirt Freak

Total posts: 273
posted November 25, 2002 09:05 PM
I took mine down till I had to clearance grind the heads on the crankshaft bolts! Lost about 8 lbs. I'm not advising you to do this, but if you make that choice, I would advise you to ***** a piece of conveyor belt to the floor of your car to act as a shield...just in case mine held up better than yours did.
(I have some belt left if you need it! LOL)

Speed Racer X
Dirt Full Roller

Total posts: 61
posted November 25, 2002 09:43 PM

Thanks for the advice. Don't know what we will end up doing, but shure don't want it to end up in someones lap. How many RPM were you turning, we need to turn 6500 to 7000.

fastrack1
Dirt Full Roller

Total posts: 73
posted November 26, 2002 07:20 PM
SPEED RACER WHY ARE U GOING TO CUT THIS FLYWHEEL DOWN WHEN U CAN BUY A NODULAR THAT WEIGHS 15 LBS FOR LESS THAN 175.00 AND THE WHOLE SET PLATE BRG AND ALL WILL WEIGH ONLY AROUND 31 LBS I LOOKED AT THIS SAME THING AND IT TAKES A LOT OF SHAVING TO GET RID OF A NOTICEABLE AMOUNT OF WEIGHT ALSO I BELEIVE YOU WIL NEED TO PUT LARGER BOLTS TO HOLD THE CLUTCH ON BECAUSE THEY ARE SMALLER ON A SIX FLYWHEEL

[This message has been edited by fastrack1 (edited November 26, 2002).]

Speed Racer X
Dirt Full Roller

Total posts: 61
posted November 26, 2002 08:26 PM
[QUOTE]Originally posted by fastrack1:
[B]SPEED RACER WHY ARE U GOING TO CUT THIS FLYWHEEL DOWN WHEN U CAN BUY A NODULAR THAT WEIGHS 15 LBS FOR LESS THAN 175.00 AND THE WHOLE SET PLATE BRG AND ALL WILL WEIGH ONLY AROUND 31 LBS I LOOKED AT THIS SAME THING AND IT TAKES A LOT OF SHAVING TO GET RID OF A NOTICEABLE AMOUNT OF WEIGHT ALSO I BELEIVE YOU WIL NEED TO PUT LARGER BOLTS TO HOLD THE CLUTCH ON BECAUSE THEY ARE SMALLER ON A SIX FLYWHEEL

Thanks for the advice. We are a lo-buck operation and the 6 cylinder stuff was free, but 31 lbs total weight sounds good. Where did you find this flywheel, presure plate, and clutch. Thanks again!!!

RaceDoctor
Dirt Full Roller

Total posts: 44
posted November 26, 2002 10:19 PM
I have done what you are describing several times.I have managed to get the 6 cyl. flywheel down to 19 lbs. You must run scattershield for safety any time you run a clutch assembly. My reason for doing this instead of buying a 15# flywheel is that I have the machining equipment in my shop so it cost me nothing but time... By the way this season the flywheel that I'm running saw 7500 RPM once (by accident) for a whole 10 lap heat race. It survived....LOL

fastrack1
Dirt Full Roller

Total posts: 73
posted November 27, 2002 06:27 PM
THE FLY WHEEL IS A GM 14085720 SCOGGINS DICKEY OR JIM PACE BOTH HAS THEM U CAN GET MORE INFO AT MORTEC.COM FOR WEBSITES ORDER A CLUTCH SET UP FOR A 68 VETTE MU 1675-1 10 SPLINES AND BE CAREFUL ON THE STARTER#P3664S AS U WILL NEED ONE BECAUSE OF THE SMALLER FLYWHEEL CAN PROBABLY DO THIS WHOLE SETUP FOR ABOUT 300.00 BUT IT IS A LOT LIGHTER AND BETTER ON THE ENGINE BE CAREFUL ALSO IF U ARE USING A 1 PIECE OR 2 PS REAR SEAL BECAUSE THEY CALL FOR A DIFFERENT FLYWHEEL IF U LOOK U MAY FIND A USED ONE WHERE A CLASS WENT TO A TRIPLE DISC ETC U CAN GET A LOT CHEAPER CHECK KARNAC .COM THEY ARE THERE SOME TIME

[This message has been edited by fastrack1 (edited November 27, 2002).]

[This message has been edited by fastrack1 (edited November 27, 2002).]

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