just inn.......
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Elder User
Joined: Jul 2006
Posts: 601
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From: Leesburg GA
just inn.......
my exhaust came in today and i have a ?
i thougt it was supposed to be 4" all the way through, why is my cat delete just 3.5 but muffler delete 4?? there are piesces that are 3.5 on one side but 4 on other.... im confused
i thougt it was supposed to be 4" all the way through, why is my cat delete just 3.5 but muffler delete 4?? there are piesces that are 3.5 on one side but 4 on other.... im confused
Former Vendor
Joined: Mar 2004
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From: Hendersonville, NC
The stock downpipe is only 3 inches, and transfers to a 3.5 inch pipe only after the catalytic converter.
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Elder User
Joined: May 2005
Posts: 968
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From: Tennesee
Jocaren,
All the MBRP systems use a 3.5 inch down pipe, a 4.0 can be MADE to fit but it'll be a bear to do and in some cases you have to bend the firewall etc. Of course the down pipe has to fit the stock cat which is 3.5 too. The cat test pipes are 3.5 as they are designed to fit the down pipe and the rest of the system after the cat and if you made them 4.0 you'd be going form 3.5 to 4.0 back to 3.5 at the after cat slip joint which would be a bad thing flow wise. Plus the VRT trubo doesn't see any extra HP or EGT drop with a 4.0 down pipe anyway so why make yourself fight it at install time etc.
Mark @ DPPI
All the MBRP systems use a 3.5 inch down pipe, a 4.0 can be MADE to fit but it'll be a bear to do and in some cases you have to bend the firewall etc. Of course the down pipe has to fit the stock cat which is 3.5 too. The cat test pipes are 3.5 as they are designed to fit the down pipe and the rest of the system after the cat and if you made them 4.0 you'd be going form 3.5 to 4.0 back to 3.5 at the after cat slip joint which would be a bad thing flow wise. Plus the VRT trubo doesn't see any extra HP or EGT drop with a 4.0 down pipe anyway so why make yourself fight it at install time etc.
Mark @ DPPI
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