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exhaust pipe dia

Messages
159
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7
Location
Easton
#1
Any thoughts on exhaust pipe diameter most companies out there are selling 2.5 inch where there is few with a 3". Anyone feel there is a performance difference or just strictly a sound thing.
 


re-rx7

1000 Post Club
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Location
Ardmore
#2
Im running 2.25'' and make the same numbers as everyone else with 2.5. Dont forget exhaust velocity also plays a part in the overall performance.
 


OP
F
Messages
159
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7
Location
Easton
Thread Starter #3
oh i know i was just trying to get the thoughts of others that might have done some testing input from both parties just to see how this car reacts to the different sizes
 


lessard.dcj

1000 Post Club
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140
Location
Petawawa
#5
not too sure if velocity is a factor as much for a boosted car, but im running 3" TB wide open!
 


airjor13

2000 Post Club
Messages
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426
Location
Centreville
#6
Anything that's out on the market right now is more then sufficient for exhaust flow. Even with the EFR / GT / GTX coming down the line, 3 inch DP into 2.5 or 3 inch TB is more then sufficient.
 


re-rx7

1000 Post Club
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Location
Ardmore
#7
2.5 is adequate up to 300 or so. I will upgrade to it when I get my larger turbo.
 


Messages
153
Likes
20
Location
Chicago
#8
As everyone before me has said, there's no reason to have 3'' piping on the FiST until you upgrade the turbo.
 


OP
F
Messages
159
Likes
7
Location
Easton
Thread Starter #9
Pretty much what I was figuring. Just wanted to see if others had the same opinion thanks for the input. I got a 5" turbo back on my truck lol[;)]
 


Messages
272
Likes
109
Location
Austin
#12
I'll see if we can dig up the old dyno plots, but the difference was in consistency, not absolute numbers. For example, if a stock car was about 160WHP/210WTQ, with a 3" CBE, it might do one run around 162WHP, then 150WHP, then 155WHP, etc, something different every time. With the 2.5" exhaust, we would see the same numbers on every pull (at least until the FMIC would heatsoak, ha!).

Ian
 


re-rx7

1000 Post Club
Messages
1,639
Likes
215
Location
Ardmore
#13
I'll see if we can dig up the old dyno plots, but the difference was in consistency, not absolute numbers. For example, if a stock car was about 160WHP/210WTQ, with a 3" CBE, it might do one run around 162WHP, then 150WHP, then 155WHP, etc, something different every time. With the 2.5" exhaust, we would see the same numbers on every pull (at least until the FMIC would heatsoak, ha!).

Ian
Gd info. Yea stock ic is for the birds.
 


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