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Discussion Starter · #1 ·
Thats my question...i want to do a cat back exaust system but ive read that you shouldnt go any more then 2" pipe on an nx2000 because you might actually lose power. Im thinking i should bump it up to 2.25", but i dont want to sacrifice any torque either...what do u guys use and what do u feel is the most effective. thanks in advance.

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1992 Nissan NX2000
White...fully loaded
 

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The 2.25 is the most common size people get. I'm going to do the same too really soon on my NX,
I always here stuff about back pressers and what not for exhaust systems but no one ever talks about scavenging could some one shed light on that ?

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92 NX2000, kyb agx, intrax springs, jwt pop,
3a Racing muffler with bonzi tip,
17 " mille miglia mm 112, Yokohama avid h4
ACT clutch on order
 

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Discussion Starter · #3 ·
Im looking to do the intake, and exaust and pulley's, and maybe later on down the line headers....what are the disadvantages of using 2.25 if any?? should i automatically use 2.25 if i go with crush bends??

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1992 Nissan NX2000
White...fully loaded
 

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For a naturally aspirated SR20, 2.25 seems to be the best. Going to a larger exhaust system will not cause you to lose power, but you will lose torque. Crush bends are more restrictive than mandrel bends so I would think 2.5" crush bends would be better.

Scavenging is what a header does. With a stock manifold, exhaust gasses from each cylinder get dumped into the same space, causing turbulence and decreasing the efficiency of the exhaust system. On a header, each cylinder dumps into it's own primary which is a tuned length so that the vacuum created by an exhaust pulse on one cylinder actually helps the flow of exhaust gas out of another cylinder.

I know that explanation is kinda awkward. Let me know if you want me to try again.



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Paul
'92 NX2000 w/ mods
 
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i have a few mods on my car and one is the 2.25" catback exhaust. when installing the japan motor with the header, i didnt tighten the flexpipe to the cat good, so it had a decent size leak. when all was done i took the car out for a spin and it was sooo fast. i fixed the exhaust leak and lost a noticeable amount of power! so i just hollowed the cat (my friend does the inspection stickers
) and the power is even better than before, moral to the story is that i would get 2.5" piping if its crush bends or 2.25" if its mandrel bent. it will work really good and you can leave your cat.
 

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<font face="Verdana, Arial" size="2">Crush bends are more restrictive than mandrel bends so I would think 2.5" crush bends would be better.</font>
I wouldn't use 2.5" with crush bends. The restriction caused by the crush bends will create more restriction that the larger diameter pipe can compensate for.

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Thomas Fox
93 NX2000
http://www.geocities.com/socalserca/Homepage.html
http://www.geocities.com/subcltr_nx2000/Homepage.html
http://sites.netscape.net/napsz/importgarage
 
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