Quote:
Originally Posted by sperry
LOLWUT?
Do a search on the venturi effect. Hell, just read this: http://en.wikipedia.org/wiki/Venturi_effect
If you want to "maintain gas velocity" like you said, you would use a smaller pipe... the transition from a smaller pipe (UP/turbo) to a larger one (DP) means lower gas velocity. My whole point was that you don't care about gas velocity in a downpipe, what you care about is getting as much gas out of the turbo as possible, i.e. volume not velocity. The ideal exhaust pipe shape is actually a trumpet bell right off the back of the turbo, anything else is a compromise, and while coating a pipe helps to keep exhaust energy (both heat and velocity) in the pipe (which is why you coat an UP, so you transfer as much exhaust energy into the turbo as possible) there is no real benefit to doing so in the DP that I can think of, except perhaps for under-hood temps... though a plain old proper heat shield should do a better job for a lot less cost than a fancy ceramic coating. |
I've never heard of a DP heat shield that fits aftermarket pipes. Please fill me in.
The ceramic coating may or may not reduce backpressure by maintaining gas velocity but it's worth it regardless as it definitely reduces underhood temps and TMIC heat soak.