Thanks gents, all help appreciated. eBay is a god send when you are in Australia and all the good gear is Stateside, but in this instance I prefer to deal with someone who knows their stuff. A lot of intakes I see on eBay are advertised as fitting any chevy 6 - 216, 235, 261, etc. I was contemplating running a dual intake with the stock exhaust for a while, and my understanding is the 235 exhaust will not mate with a 216 intake. Also there is a difference between 216 and 235 carb sizes and manifold bore dia. Am I correct in assuming I can run a 216 manifold on my 235 if I run headers? If I do run the 216 manifold, will the reduction in bore size negate any benefit from the daul carbs?
