Exhaust

[psycho98gst]

I bought a exhaust of the internet and I need some technical help please. The down pipe I bought is 2.5 inch at the O2 sensor yet it expands to 3 inches but the test pipe is only 2.5 will this seal properly?? Also the cat back is greddy evo and seems to be 2.25 inch except for the mid pipe on one end that seems to be 2 inches. is this a 2.5 exhaust?? with the mid pipe reducing to 2 inches am I going to get the flow I'm looking for?? PLEASE HELP!

 

[dsm4life]

Originally posted by psycho98gst
I bought a exhaust of the internet and I need some technical help please. The down pipe I bought is 2.5 inch at the O2 sensor yet it expands to 3 inches but the test pipe is only 2.5 will this seal properly?? Also the cat back is greddy evo and seems to be 2.25 inch except for the mid pipe on one end that seems to be 2 inches. is this a 2.5 exhaust?? with the mid pipe reducing to 2 inches am I going to get the flow I'm looking for?? PLEASE HELP!

as was told to me last time , your only gonna get as good flow as your smallest piece. I heard that 2.5 from the o2 is fine.

 

[psycho98gst]

okay thats great that the flow will be good at the O2, but the exhaust system seem to go from 2.5 to 3 to 2.5 to 2 at the conections will this work or will the 2 inch constrict the exhaust?? also will these seal properly?? Any help is much appreciated!! THANKS!!

 

[dsm4life]

if your asking will it constrict the flow , yes. If you are going from 2.5 to 3 ,3 is wide open flowing nicely then you are going from 3 to 2.5 = problem now you have air restriction then from 2.5 to 2 = restriction
think of it as a jammed highway

you have 2.5 lanes that turn into 3 lanes (all cars are flowing faster now)
then 3 lanes goes back down to 2.5(cars not going as fast some conjestion)
then from 2.5 to 2 (even more conjestion)

I hope that helps .

 

[psycho98gst]

i put the whole exhaust under the car and it looks like the down pipe completly takes the place of the stock downpipe and the cat do I need to goto a welder and have him weld in the test pipe and take off some of the mid pipe or What??

 

[rowlex]

NO, it sounds like you have a cat-eliminator downpipe, sell the test pipe have the cat-back welded on, loose the flange's that restrict your flow.

 

[psycho98gst]

okay thanks I think your right I have a cat eliminator down pipe thanks

 

[rowlex]

no problem, goodluck!