Andyinchville1
Veteran Member
HI all,
Looking to get some PM work done to my car and I figure while stuff is being worked on / apart might as well upgrade a little too.
I know many people say the stock intake and exhaust are sufficient for a relatively stock situation like mine but I did have a relatively stock 1993 Dodge with the Cummins and a 4" straight pipe from turbo and it sounded sweet , had lower EGTs (not that I had EGT issues tho) and helped with fuel economy (granted some of that may have been the result of me babying it more after the exhaust upgrade since it was pretty loud and I didn't want to get grief from the man so I figured I'd do the same to the Jetta.
Anyways, I would like some input to help me make a choice ...
I am currently debating between ID parts 2.5 inch down pipe and Kerma's 3" downpipe.
1) I have a question regarding flow .... According to ID Parts, their 2.5 inch downpipe features a custom cast piece to gradually "flair up" to the 2.5" diameter downpipe pipe (I'm guessing this is similar to what my Dodge system had as far as a transitional "cone" to smooth / help prevent turbulence as the exhaust gas flows out of the turbo
I am not sure if Kerma's down pipe has the same feature ... i.e. a smooth transition from the turbo exhaust outlet to the 3" pipe..
Given the above, which downpipe flows better the 2.5" with smooth transition or the 3" non transition downpipe ?
2) Does the optional resonator make a real difference in drone reduction ?
Thanks in advance for all input / help
Andrew
FWIW - At the same time I'm upgrading the exhaust I am also going to install (or have installed) a BRM intake manifold with adapter (it's only been sitting in my shed for what seems like a year by now!) to help the intake side as well ...
Looking to get some PM work done to my car and I figure while stuff is being worked on / apart might as well upgrade a little too.
I know many people say the stock intake and exhaust are sufficient for a relatively stock situation like mine but I did have a relatively stock 1993 Dodge with the Cummins and a 4" straight pipe from turbo and it sounded sweet , had lower EGTs (not that I had EGT issues tho) and helped with fuel economy (granted some of that may have been the result of me babying it more after the exhaust upgrade since it was pretty loud and I didn't want to get grief from the man so I figured I'd do the same to the Jetta.
Anyways, I would like some input to help me make a choice ...
I am currently debating between ID parts 2.5 inch down pipe and Kerma's 3" downpipe.
1) I have a question regarding flow .... According to ID Parts, their 2.5 inch downpipe features a custom cast piece to gradually "flair up" to the 2.5" diameter downpipe pipe (I'm guessing this is similar to what my Dodge system had as far as a transitional "cone" to smooth / help prevent turbulence as the exhaust gas flows out of the turbo
I am not sure if Kerma's down pipe has the same feature ... i.e. a smooth transition from the turbo exhaust outlet to the 3" pipe..
Given the above, which downpipe flows better the 2.5" with smooth transition or the 3" non transition downpipe ?
2) Does the optional resonator make a real difference in drone reduction ?
Thanks in advance for all input / help
Andrew
FWIW - At the same time I'm upgrading the exhaust I am also going to install (or have installed) a BRM intake manifold with adapter (it's only been sitting in my shed for what seems like a year by now!) to help the intake side as well ...
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