im wondering, if i get an RMF header, what do i need to complete the exhaust, do i need a high flow cat? and what size 2.25" or 2.5" and then what size for the exhaust piping?

 

you will need a 2.5" flex pipe. U dont necessarily need a high flow cat, but i replaced mine with a 2.5" cat while i was doing the header

 

as a general rule, you want your exhaust to be as big as if not bigger than your collector....

 

why is that?

 

cuz if you have exhaust piping that is smaller than the collector its like blowing through a regular drinking straw. If you have the same size exhaust or bigger, its like blowing through a "big gulp" straw (hahaha)

 

think about it dude....you have air coming thru the collector....no do you want it to flow out unresricted, or bottleneck it....

if you put a smaller exhaust on you will bottleneck it...

if you couldnt have figured that out for yourself i worry for you...

 

this is why megaphone collectors are so much greater. at the 4-1 merge, the collector is relatively small and gradually gets bigger, same sort of concept goes with the rest of the exhaust

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mgags7 &raquo;</TD></TR><TR><TD CLASS="quote">

if you couldnt have figured that out for yourself i worry for you...</TD></TR></TABLE>

lol, i was wondering if you meant the collector from the header or the collector on the exhaust

 

haah yeah i know that but ok say i get an RMF header, do you know what the size of the piping is at the end of it? like 2.5"?

 

yes 2.5

 

ok so its 2.5", then i need a test pipe that is 2.5" and say a greddy evo 2 will bolt up to that? im just really confused on this.

 

as long as your pipes are equal to or bigger than 2.5" you are fine....i dont see whats so confusing about it....

 

i read somewhere if it's too big and you're not producing enough power to utilize the diameter of the 2.5," it is at a disadvantage? is this true?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by khalal538 &raquo;</TD></TR><TR><TD CLASS="quote">i read somewhere if it's too big and you're not producing enough power to utilize the diameter of the 2.5," it is at a disadvantage? is this true?</TD></TR></TABLE>

yeh thats true... but actually you loose lower end torque but gain the top... so its not good if ur runnin in low rpms all the time....(daily driver) I noticed the loss in mine...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 98vtec &raquo;</TD></TR><TR><TD CLASS="quote">cuz if you have exhaust piping that is smaller than the collector its like blowing through a regular drinking straw. If you have the same size exhaust or bigger, its like blowing through a "big gulp" straw (hahaha)</TD></TR></TABLE>

the regular straw and the big gulp straws are the same diameter up here at 7-11, big gulp straws are just longer.

i think u should compare it to a slurpee straw those are fatter