Lightweight flywheel

[Z Ya Later]

Well, I'm thinking about swapping out the flywheel down the road and am wondering...would a lightweight flywheel throw off the balance of the crank? If I remember correctly, the LT1 is externally balanced, right? Thanks in advance.

[Z Ya Later]

Any takers on this one?

[Jeff_in_Atl]

Well, I'm thinking about swapping out the flywheel down the road and am wondering...would a lightweight flywheel throw off the balance of the crank? If I remember correctly, the LT1 is externally balanced, right? Thanks in advance.

There is a spec to the balance of a LT1 flywheel. (It is externally balanced) I think it is 95 grams at something like 72 degrees off of TDC. Don't quote me on that. Anyway if the flywheel is made to the specs required for a LT1 then it should be OK.

[Z Ya Later]

There is a spec to the balance of a LT1 flywheel. (It is externally balanced) I think it is 95 grams at something like 72 degrees off of TDC. Don't quote me on that. Anyway if the flywheel is made to the specs required for a LT1 then it should be OK.

So, if I end up going to a Spec 2 or 2+ clutch with lightweight flywheel for the LT1, I won't have to worry about the crank being off balance, right? Since its for the LT1, in theory, it should have the spec-ed weight at necessary position you mentioned (95g at 72 deg. from TDC), and the weight reduction is all in the rest of the flywheel itself, right? Thanks for your help Jeff.

[Jeff_in_Atl]

So, if I end up going to a Spec 2 or 2+ clutch with lightweight flywheel for the LT1, I won't have to worry about the crank being off balance, right? Since its for the LT1, in theory, it should have the spec-ed weight at necessary position you mentioned (95g at 72 deg. from TDC), and the weight reduction is all in the rest of the flywheel itself, right? Thanks for your help Jeff.

Your choice of clutches doesn't matter when choosing the flywheel in regards to weight. The clutch disc and pressure plate are balanced to zero. My neighbor balanced mine with the clutch and pressure plate and match marked them to be sure but in theory it shouldn't matter.

Like I said, if the flywheel is made for the LT1, it shouldn't matter.

[Z Ya Later]

Your choice of clutches doesn't matter when choosing the flywheel in regards to weight. The clutch disc and pressure plate are balanced to zero. My neighbor balanced mine with the clutch and pressure plate and match marked them to be sure but in theory it shouldn't matter.

Like I said, if the flywheel is made for the LT1, it shouldn't matter.

Oh I know the clutch won't matter, I was just using that as a hypothetical situation. At any rate, thanks for the help Jeff . Now I won't be so hesitant to buy one.

[Trash man]

any1 kno the spec on the 400 sbc? and i think i kno the answer but i better ask anyways, would the LT1 flywheel work on a 400 sbc? thanks

[DeWynter]

any1 kno the spec on the 400 sbc? and i think i kno the answer but i better ask anyways, would the LT1 flywheel work on a 400 sbc? thanks

THe 400 sbc needs a specific weighted flywheel. It also requires a specific weighted harmonic ballancer, as it is externaly balanced. You can use a regular pre 86 flywheel on it with an aftermarket weight.
Balance plate