>From: "Dave Studly" <[EMAIL PROTECTED]> >Subject: RE: [Chevelle-list] 487 heads >Date: Fri, 10 Dec 2004 14:16:20 +0000 > >Are they 487 or 487X castings? I have a set of the 487X castings on my 406, >but were told that they were from a '71 LT-1 when I got them back in '91 or >'92. I seem to remember looking the numbers up years ago and verifying this.
Just the plain 487s. >I don't know what the difference (if any) is between the two castings. IIRC an "X" signified about a 10% increase in intake runner volume. >As for their performance potential, I've gone high 12s with those heads on >my engine. 1.94/1.50 valves, very mild port cleanup and gasket match. >Summit 234/244 cam, Performer RPM intake. There are certainly better heads If I use them they'll be going on a mild 350 for my '86 K10. I don't think I'll be too upset if I don't get into the 12s. ;^) >From: "Brian Knight" <[EMAIL PROTECTED]> >Subject: RE: [Chevelle-list] 487 heads >Date: Fri, 10 Dec 2004 22:34:52 +0000 > >According to Moretec.com, they came on '71 LT1 350 330hp. I'm sure they >probably came on others as well, though. I have a set of these myself, and Looks like the 487 might've been the base 1.94/1.5 head for '71 and was used for low to midlevel performance applications. Certainly fine for what I'd be using them for! Brad
