Guaranteed, they are 901 and 902. It is a VERY easy mistake to make. That 9 can look like an 8 and I have seen 6s that look like 8. It is a terrible shame that these manifolds will not fit a Chevelle. Otherwise I would have them on mine. I swear to God, I absolutely do not understand why Chev quit making 2 1/2in manifolds for the SB (and while we're at it, I don't understand why they quit making the removeable center section rear end, like Ford 9"). They never did make the style that goes under the plugs in 2 1/2in. Everyone is right, these are (were) only hipo 327, vettes and pass 62-65 only, 300-375hp (except the 300hp with auto tranny got 2in).If he is asking a good price, buy them anyway. They bolt up to ANY SB. There were originally 4 different versions of the 2 1/2in Ram Horn manifold, Chev still sells 3 of them. I think they are cast in Mexico. This would be an EXCELLENT manifold for a strong 350-400 in a Chevelle for someone who wanted to keep a stock type exhaust system, if it would fit. Don't let him rape you on the price, because, as I say, you can still buy new ones from Chev.
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[This message has been edited by DZAUTO (edited 06-10-99).]