Secondary Exhaust Pipe Questions
#1
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Suppose I have a 355CI Chevy motor making 450 horsepower at the crank. I'm having a set of 1 3/4" shorty headers (California Legal for my car) with a 3 inch collector custom built for my car. These will be flowing into seperate cats. The pipes after the cats will "Y" together and flow into a 3 1/2" mufflex system.
Question 1: What size secondary pipe would be the best size? Say 2 1/2", 2 3/4", 3" or other?
Question 2: If a pipe smaller than the 3" collector is best, then would it be best to neck the pipe down at the collector or run a 3" pipe some distance before necking down?
Question 3: Would it be best to run 3" pipes to the Cats than neck down after the cats or maybe 3 inch all the way to the "Y" pipe?
Question 4: Is there a 4 into 1 merge collector that is best for shorty headers?
I have read David Vizard's article on exhaust but I'm not sure on the collector length for a street car with cats etc. I know there is a lot of knowledge on this board and hopefully someone has been down this road before.
Question 1: What size secondary pipe would be the best size? Say 2 1/2", 2 3/4", 3" or other?
Question 2: If a pipe smaller than the 3" collector is best, then would it be best to neck the pipe down at the collector or run a 3" pipe some distance before necking down?
Question 3: Would it be best to run 3" pipes to the Cats than neck down after the cats or maybe 3 inch all the way to the "Y" pipe?
Question 4: Is there a 4 into 1 merge collector that is best for shorty headers?
I have read David Vizard's article on exhaust but I'm not sure on the collector length for a street car with cats etc. I know there is a lot of knowledge on this board and hopefully someone has been down this road before.