OEM Exhaust Manifold Size Difference
01-28-2010, 11:25 AM
#1
OEM Exhaust Manifold Size Difference I have some 00' exhaust manifolds that I will be porting for when I swap out my longtubes. I took some measurements and the outlets are "roughly" 2.5" on the drivers side, and only 2 1/4" on the passengers side.
This got me to thinking and I've never heard it talked about...why would one be smaller than the other? Nobody makes an aftermarket exhaust with differing collector diameters, so what would the thinking behind doing this at the factory be? Anybody know the answer, or have any thoughts?
This got me to thinking and I've never heard it talked about...why would one be smaller than the other? Nobody makes an aftermarket exhaust with differing collector diameters, so what would the thinking behind doing this at the factory be? Anybody know the answer, or have any thoughts? 
01-31-2010, 03:07 AM
#3
my guess would be that the passenger side manifolds need more clearance to fit in such a tiny space as compared the the drivers side.
i justify my argument by this: the factory y pipe is the only y pipe that has a flattened pipe on the d/s....why, clearance issues. its jst cheaper to make something smaller than do something more expensive. after market companies dont need to flatten their y-pipes for better clearance..they just manufactured their product better than factory standards
i justify my argument by this: the factory y pipe is the only y pipe that has a flattened pipe on the d/s....why, clearance issues. its jst cheaper to make something smaller than do something more expensive. after market companies dont need to flatten their y-pipes for better clearance..they just manufactured their product better than factory standards
02-01-2010, 01:27 PM
#4
my guess would be that the passenger side manifolds need more clearance to fit in such a tiny space as compared the the drivers side.
i justify my argument by this: the factory y pipe is the only y pipe that has a flattened pipe on the d/s....why, clearance issues. its jst cheaper to make something smaller than do something more expensive. after market companies dont need to flatten their y-pipes for better clearance..they just manufactured their product better than factory standards
i justify my argument by this: the factory y pipe is the only y pipe that has a flattened pipe on the d/s....why, clearance issues. its jst cheaper to make something smaller than do something more expensive. after market companies dont need to flatten their y-pipes for better clearance..they just manufactured their product better than factory standards
02-01-2010, 02:21 PM
#5
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well they may make the passenger side smaller to accomodate for the flow difference so that in all actuallity the exhaust flow is the same amount on each side where it meets in the y pipe there for causeing less turbulance and better performance thats my only idea behind that cause a smaler inside diameter would slow down flow on the pipe with less bends(passenger side ) that way after the drivers side makes its bends and everything they flow the same but thats just my idea
02-02-2010, 06:55 AM
#6
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It's possible that it showed weakness or cracked during a test in that area and needed more material for strength, but honestly I don't know.
That is weird. Good catch.
That is weird. Good catch.
