Hello,

I need to buy a flywheel for a first gen 350. I visited the Summit website, and I noticed that there are steel and aluminum flywheels, with various weights (15-40 lbs. on average), different diameters and two different tooth count (153 or 168). I have no idea which one to buy. Perhaps someone can give me recommendations if I provide engine specs and application.

Motor:
350 cid .040 over
forged crank and rods
10:1 comp.
750 dp Holley
Wieand team-g intake
iron heads, 2.02/1.60
1.6 rocker arms
comp cam 288 dur. .488" lift
Muncie M21 close ratio 4 speed

Car:
1962 Stratochief (similar to a Bonneville) weighs around 3600 lbs.
gearing is not determined, somewhere around 3.73:1
street tires, normal diameter

This vehicle is primarily for street use.

Does anyone have any suggestions?

Thanks.

It is better to use a heavier flywheel on the street. Light weight flywheels ae generally used for racing when you want the motor to rev quicker.

Hello,

I need to buy a flywheel for a first gen 350. I visited the Summit website, and I noticed that there are steel and aluminum flywheels, with various weights (15-40 lbs. on average), different diameters and two different tooth count (153 or 168). I have no idea which one to buy. Perhaps someone can give me recommendations if I provide engine specs and application.

Motor:
350 cid .040 over
forged crank and rods
10:1 comp.
750 dp Holley
Wieand team-g intake
iron heads, 2.02/1.60
1.6 rocker arms
comp cam 288 dur. .488" lift
Muncie M21 close ratio 4 speed

Car:
1962 Stratochief (similar to a Bonneville) weighs around 3600 lbs.
gearing is not determined, somewhere around 3.73:1
street tires, normal diameter

This vehicle is primarily for street use.

Does anyone have any suggestions?

Thanks.

How do you intend to drive the car? The aluminum flywheel has a lower moment of inertia, meaning the engine will rev faster, but it won't last as long on the street as a good steel wheel. It will also warp easier due to the different metals in it (the wheel itself is aluminum, but the clutch disk surface is still steel).

Look under the car at the starter bolting to the engine. If the bolts are staggered/offset you'll need the big flywheel. If the bolts are inline, direct across from each other you'll need the smaller flywheel. All steel flywheels are best for street use in general.

The smaller flywheel goes with the 10.375 diameter clutch and the bigger goes with the 11.00 clutch. But verify this with Summit, which might also impact your starter selection.

Stay away from the aluminum flywheels for street use. Aside from weight saving, there is no advantage and the steel one will outlast it by far.

Bob

The other thing to consider is whether the rear main seal is two-piece or one. The flywheels are different for each crank design. The 1-piece RMS design needs the "bat weight" in the flywheel since it is missing from the crank flange. What year is the block?