selecting a flywheel, can be rather difficult for newer guys as most of them want to get something like (THE RACERS USE) and that can be a BIG mistake, ESPECIALLY on a typical 3500 lb street car, and depending on the application, for a street car youll rarely find that a steel flywheel in the 30lb-40 lb range is a bad choice, while a light weight aluminum flywheel almost always is the wrong choice on a street car.but ID sure suggest getting an SFI rated flywheel and a BLOW PROOF BELL HOUSING AND CLUTCH ASSEMBLY
keep in mind heavier BILLET STEEL flywheels absorb heat more effectively and are usually far easier to ballance and less prone to warping or cracking, than either cast iron, which has a bad habbit of cracking and flying apart at high stress and rpm levels or aluminum that tends to warp or have the surface mar under stress/heat loads.
youll want to get the correct dia. (on a chevy thats usually 168 tooth dia. but can ocasionally be the smaller 153 tooth dia. and get a flywheel thats ballanced (INTERNALLY OR EXTERNALLY) to match your application.
theres also one piece and two piece rear seals, and bolt paterns matching 10".10.4", 11" clutchs and both sbc and BBC designs so shop carefully and ask lots of questions
Counter Weight Kit General Motors Flywheel (1A/2C/3C/4C)
Fits Externally Balanced Applications
1986-1999 SBC
1970-1990 BBC
1991-1997 BBC
1970-1980 SBC 383/400
the clutch disc
is very likely to swell un-evenly, and slip under loads, both conditions tend to result in clutch failure eventually so the source of the oil or brake fluid should be found and the problem corrected THEN a new clutch disc installed with a re-conditioned pressure plate
and resurfaced flywheel with a NEW throw out bearing
old heat checked OEM cast flywheels like this are a potential problem, as under high loads and high rpms they have been known to explode.
non-billet, OEM, cast iron, flywheels that are not sfi rated are significantly lower strength designs
a resurfaced OEM CAST flywheel looks like new, but can be hiding serious structural flaws
use of a SFI rated flywheel and a blow proof bell housing, with a block saver plate and an sfi rated pressure plate, to contain it if the parts were to fragment under high rpms are highly recomended
http://www.gmpartsdirect.com/performanc ... D=913.html
http://www.ramclutches.com/Products/flywheel_apps.htm
http://store.summitracing.com/egnsearch ... wordSearch
http://store.summitracing.com/egnsearch ... wordSearch
http://store.summitracing.com/egnsearch ... wordSearch
there are 153 (about 12")
and 168 tooth (about 14")
fly wheel,
but in every case the starter must be mounted, on the block with the correct matching bell housing on the block to correctly contact the flywheel SIZE your using , if you have a choice the larger 168 tooth flywheel had the advantage of both more leverage for the starter as the ring gear is mounted further from the crank center-line and more surface area for a larger clutch , surface to grab and more surface area to dissipate heat that will build up.
Default SBC Flywheel & Flexplate part numbers
Small Block Chevy Flywheel Part Numbers
Part # DIA. Teeth Comments
3991406 Flywheel, LW Nodular Iron for HD 10.5" Clutch
3991469 14" 168 two-piece seal, internally balanced
3986394 14" 168 400 External balance, two-piece seal
10105832 14" 168 86-later, one-piece rear seal, ext. balance
14088671 12.75" 153 86-later, one piece rear seal, int. balance
14085720 12.75" 153 Lightweight (15 lbs.), nodular iron, two-piece seal, int bal Will work with a clutch diameter of 10.4" only. Crank flange bolt pattern is 3.58". Will work with a clutch diameter of 10.4" OR 11.0". Crank flange bolt pattern is 3.0"
14088646 12.75" 153 86-up, Lightweight (15 lbs.), nodular iron, one-piece rear seal, ext bal
14088648 14" 168 86-up, one-piece rear seal, ext. balance
14088650 12.75" 153 86-up, one-piece rear seal, ext balance Will work with a clutch diameter of 10.4" only. Crank flange bolt pattern is 3.0"
10174482 89-up with six-speed m/t, requires starter (10455709)
Common clutch sizes are: 10.4", 11.0", and 11.85". Some flywheels are drilled for two different clutch patterns.
12.75" are usually 153 tooth and the other larger 14" diam. are 168 tooth flywheel or flex plate designs, the larger 14"/168 tooth designs fit the much stronger 11" clutches.... obviously the 14" can use a larger clutch, but require a larger bell housing that is why some stock bell housings won,t fit the larger fly wheels and of course the starter used must match
http://www.4speedconversions.com/chevy-bellhousings.html
read these also
viewtopic.php?f=71&t=584&p=757&hilit=+bellhousing#p757
viewtopic.php?f=71&t=447&p=921&hilit=+clutch#p921
READ THESE THREAD's
and don,t skip the sub linked info
http://garage.grumpysperformance.com/index.php?threads/engine-balancing.3900/
http://garage.grumpysperformance.com/index.php?threads/engine-balancing.3900/#post-57940
http://garage.grumpysperformance.com/index.php?threads/redline.343/
http://garage.grumpysperformance.com/index.php?threads/types-of-crankshaft-steel.204/
http://garage.grumpysperformance.co...s-to-casting-numbers-and-info.632/#post-53467
http://garage.grumpysperformance.com/index.php?threads/ballancing-the-components.141/#post-5391
keep in mind heavier BILLET STEEL flywheels absorb heat more effectively and are usually far easier to ballance and less prone to warping or cracking, than either cast iron, which has a bad habbit of cracking and flying apart at high stress and rpm levels or aluminum that tends to warp or have the surface mar under stress/heat loads.
youll want to get the correct dia. (on a chevy thats usually 168 tooth dia. but can ocasionally be the smaller 153 tooth dia. and get a flywheel thats ballanced (INTERNALLY OR EXTERNALLY) to match your application.
theres also one piece and two piece rear seals, and bolt paterns matching 10".10.4", 11" clutchs and both sbc and BBC designs so shop carefully and ask lots of questions
on the plus side , when your working with the Chevy v8 engines SBC and BBC, if you select the correct two piece or one piece rear seal components, many aftermarket manufacturers of flex plates and flywheels to reduce manufacturing costs , build a neutral balance flywheel or flexplate and simply bolt on or weld on a weight to allow the same basic part to work with both potential combosshelbysnake said:
Counter Weight Kit General Motors Flywheel (1A/2C/3C/4C)
Fits Externally Balanced Applications
1986-1999 SBC
1970-1990 BBC
1991-1997 BBC
1970-1980 SBC 383/400
the clutch disc
is very likely to swell un-evenly, and slip under loads, both conditions tend to result in clutch failure eventually so the source of the oil or brake fluid should be found and the problem corrected THEN a new clutch disc installed with a re-conditioned pressure plate
and resurfaced flywheel with a NEW throw out bearing
old heat checked OEM cast flywheels like this are a potential problem, as under high loads and high rpms they have been known to explode.
non-billet, OEM, cast iron, flywheels that are not sfi rated are significantly lower strength designs
a resurfaced OEM CAST flywheel looks like new, but can be hiding serious structural flaws
use of a SFI rated flywheel and a blow proof bell housing, with a block saver plate and an sfi rated pressure plate, to contain it if the parts were to fragment under high rpms are highly recomended
http://www.gmpartsdirect.com/performanc ... D=913.html
http://www.ramclutches.com/Products/flywheel_apps.htm
http://store.summitracing.com/egnsearch ... wordSearch
http://store.summitracing.com/egnsearch ... wordSearch
http://store.summitracing.com/egnsearch ... wordSearch
there are 153 (about 12")
and 168 tooth (about 14")
fly wheel,
but in every case the starter must be mounted, on the block with the correct matching bell housing on the block to correctly contact the flywheel SIZE your using , if you have a choice the larger 168 tooth flywheel had the advantage of both more leverage for the starter as the ring gear is mounted further from the crank center-line and more surface area for a larger clutch , surface to grab and more surface area to dissipate heat that will build up.
Default SBC Flywheel & Flexplate part numbers
Small Block Chevy Flywheel Part Numbers
Part # DIA. Teeth Comments
3991406 Flywheel, LW Nodular Iron for HD 10.5" Clutch
3991469 14" 168 two-piece seal, internally balanced
3986394 14" 168 400 External balance, two-piece seal
10105832 14" 168 86-later, one-piece rear seal, ext. balance
14088671 12.75" 153 86-later, one piece rear seal, int. balance
14085720 12.75" 153 Lightweight (15 lbs.), nodular iron, two-piece seal, int bal Will work with a clutch diameter of 10.4" only. Crank flange bolt pattern is 3.58". Will work with a clutch diameter of 10.4" OR 11.0". Crank flange bolt pattern is 3.0"
14088646 12.75" 153 86-up, Lightweight (15 lbs.), nodular iron, one-piece rear seal, ext bal
14088648 14" 168 86-up, one-piece rear seal, ext. balance
14088650 12.75" 153 86-up, one-piece rear seal, ext balance Will work with a clutch diameter of 10.4" only. Crank flange bolt pattern is 3.0"
10174482 89-up with six-speed m/t, requires starter (10455709)
Common clutch sizes are: 10.4", 11.0", and 11.85". Some flywheels are drilled for two different clutch patterns.
12.75" are usually 153 tooth and the other larger 14" diam. are 168 tooth flywheel or flex plate designs, the larger 14"/168 tooth designs fit the much stronger 11" clutches.... obviously the 14" can use a larger clutch, but require a larger bell housing that is why some stock bell housings won,t fit the larger fly wheels and of course the starter used must match
http://www.4speedconversions.com/chevy-bellhousings.html
read these also
viewtopic.php?f=71&t=584&p=757&hilit=+bellhousing#p757
viewtopic.php?f=71&t=447&p=921&hilit=+clutch#p921
READ THESE THREAD's
and don,t skip the sub linked info
http://garage.grumpysperformance.com/index.php?threads/engine-balancing.3900/
http://garage.grumpysperformance.com/index.php?threads/engine-balancing.3900/#post-57940
http://garage.grumpysperformance.com/index.php?threads/redline.343/
http://garage.grumpysperformance.com/index.php?threads/types-of-crankshaft-steel.204/
http://garage.grumpysperformance.co...s-to-casting-numbers-and-info.632/#post-53467
http://garage.grumpysperformance.com/index.php?threads/ballancing-the-components.141/#post-5391
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