Out of curiousity why does everyone use 2.5" on the crossover pipe
#161
And you are correct about the adding heat part. For simplicity, just assume the basic Otto cycle where you just add heat at tdc.
#162
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From: Port Tobacco, MD
It would be interesting to see what your calcualtion says. Reguardless what the calculator says, 2.5" will support 2400hp and has on multiple cars. My calculator has worked for the last few years and seems to be right on when the numbers are within the sweet spot.
#166
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From: Port Tobacco, MD
2 - 2.5" pipes has supported enough power to go 164mph @ 3350 to the 1/8 mile. I have the same crossover on the car now but on methanol with a bigger turbo. Looking for 181-183 to the 1/8 mile.
#167
#169
Most people don't realize that the pressurized exhaust gas pre-turbine is of far less volume than exhaust on your typical NA engine, so it doesn't need nearly as much flow area.
This makes me wonder what are the implications pertaining to the exhaust port and valve. Can they also be downsized? This may make sense if it means you can fit a larger intake valve in there.
Another myth is that the downpipe shouldn't be oversized because you lose velocity. I know quite a bit about turbines and can assure you that the downpipe can not be oversized.
#171
Are you measuring inside or outside diameter on the pipe? Also what wall thickness? Ive got some 2" stainless steel pipe. It is all food grade pipe. Its 2" outside diameter 1 7/8" inside. 1/16 wall. Will this work on a 5.3 with a t6 s475? Reason for using is I can get all pipe and bends for free.
#173
I've been calculating everything with 16ga wall other than possibly where I was trying to see if I could match some of Phil's numbers and I noticed he was using O.D. just to ballpark some things. Oh hell, I don't know, I might have been using I.D. for that too, I have the I.D. areas of all the different sized pipes on a paper here next to my keyboard. Haha....
I think Phil mentioned that he ballparks his calculations with O.D. just to be simple, and then works with I.D. when he's really fine tuning things.
I think Phil mentioned that he ballparks his calculations with O.D. just to be simple, and then works with I.D. when he's really fine tuning things.
#175
#180