I am switching to a manual transmission. I know that I can choose between aluminum (15 lbs) and steel (30 & 40 lbs) flywheels. What is the best choice for a 454 1970 Chevelle mostly street, a few trips to the strip? The engine has alum heads, Crane 296 cam and runs to about 6500 rpm.
Thanks.

I always thought an aluminum flywheel was for racing only.

What transmission gearing and rear gearing are you running ?

Ooops. I forgot. I have 3:55 gears, tires are about 25" tall and the trans will have a 2.87 first gear.

Street-40lb.

Bill,

I agree with Tom, I would suggest the casting number 3993827, it's ID number is 3993457. It is drilled for an 11" clutch. You can get them at GM Perf parts or Advanced Auto (their part number is 04039), cost $140. Also, this flywheel has a counter weight when cast, which is needed to keep your "externally balanced" engine in balance. If you decide to use the Alum flywheel, you should check and see if it will keep a Mark IV in balance.

Fred.

If I decide to use a performance 12 inch clutch assembly will the extra weight over an 11 inch matter in this?

A friend of mine used aluminum flywheels on circle track cars so when you came out of the corner they would rev up quicker. But he even uses steel now.

3.55, 2.87 & 25.5 tires? I wouldn't use a 40 with a 270 cam. Try and find something in the mid 30's.
You should have plenty of torque and gear multiplication.

I've tried them all and i'd suggest a 30 pound aftermarket steel wheel. The cast iron factory flywheels are a recipe for disaster and i know of NO steel flywheels offered by Chevrolet. This is the most important safety item you will ever buy for a stick car. Also get a scattershield from Lakewood or McLeod. A fourty pound flywheel is too heavy for a 454 and will produce nothing but tire smoke. The Aluminum flywheels are hard to drive on the street as they are hard to find the right rpm to leave at, (too light). A good double disc clutch and pressure plate setup might be a good idea with a lot of torque.

I've driven a mild 454 in a tire-challenged '68 Camaro using the 12 lb. nodular iron lightweight GM flywheel. Damn, that's a lot of fun. Revs like a sewing machine plugged into 220V. On the other hand, leaving from a stop was a matter of bogs or tiresmoke. Usually both. No such thing as smooth takeoff.

Look for a big "N" on the back of it b/c that will indicate nodular-iron and it is a lot tougher then regular gray-iron flywheels. It's the h-d cast-iron for stock use.

pdq67

The brand of parts I am looking at are Mcleod and they have a 30# and 40# steel unit. It sounds like I can't go wrong with either.

40's come on dually's. So it will rev like a truck. I know because I've had a dually and a 40 on my 454.
I got the 25lb steel McCleod based on that was the smallest they thought would work on the street for my combo. 3.04 1st gear and 3.07 gears. Same as about a 3.90 and a Muncie. One of these days I'll see how it runs. I had a 35 on my 12-1 396 w/3.08's.
Started in second a few times just fine. Still rev'd way slow compared to a sbc. But acceptable.