Thanks for the help. I had heard from others that the RPM intake was not ideally suited for the 350. I previous owner believed that it was an HO car as it had a period correct 4bbl carburetor and intake. I believe these were probably installed by the dealer in 69 at buyers request. My understanding is that only HO cars were built with 4bbl carbs so when people look under hood and see a 4bbl and factory intake they assume HO and do not confirm block code or head numbers. I have yet to decide if I will go back to original cast iron intake which I have or purchase a Performer intake.