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what size pipe for exhaust

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Old 12-29-04, 07:17 PM
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newyorksc
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Default what size pipe for exhaust

anybody with exhausts on their sc?

what is the best recommended size?

i plan on buying the JIC bullet twin 505S ST

they offer :

Pipe size 60mm, 65mm, or 80mm.
Tip size is 90mm, 100mm or 116mm.

what is the recommended pipe size? for more acceleration is it recommended to go with a lower pipe size and for higher top speed go for higher pipe size?

is this correct? well, what would be recommended for a daily driver in the city (new york)?

thanks, i appreciate it. also, let me know if any better exhaust is available. i would like to get an APEXi n1 but I can't find it for the SC, so i'm going with the JIC. anybody recommend this one or one better? right now i have my mind set on the JIC one.

thanks, bye
Old 12-29-04, 09:51 PM
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lex400sc
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I've messed with my exhaust a bit and I found the acceleration is most improved with a magnaflow dual center cat...



...and 2.5" dual piping into a 2.5-inch muffler. Sounds real throaty too after it all breaks in
Old 12-29-04, 09:58 PM
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MikeFD3S
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For a non turbo NA i6 with dual exhaust, the largest you should go is 60mm piping.

Since most power gains are dictated by the pipe routing, and piping diameter, its up to your exhaust fabricator. Also, a single exit exhaust will flow better than the more aesthetically pleasing dual.

Most straight through mufflers have similar flow characteristics, so I would consider sound output when choosing your muffler.

Apex N1 and JIC Bullet are notoriously loud and raspy mufflers. A bit too 'young' IMO
Old 12-30-04, 12:59 AM
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newyorksc
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thanks for your input

where would you suggest i go to purchase the magnaflow exhaust?

in terms of fastest shipping and packaging?

Last edited by newyorksc; 12-30-04 at 01:04 AM.
Old 12-30-04, 02:12 AM
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BLK13X
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I dunno your situation, I'm just going be your SN.

* Is your SC turbo? Either 1JZ or 2JZ, I would recommend an exhaust system from the turbos. On a 1JZ, many people have had good success from an exhaust starting from the turbos... so on a 1JZ turbo (for example)...
* 2x2.5" twin dump pipes to a 3" collector and flexijoint
* Hi-flow cat
* 3" midpipe to Y-split
* 2x2.5" rear pipes, twin resonators and mufflers.

Just a suggestion.


Jose
Old 12-30-04, 06:49 AM
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qtb33
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If your NA your limited by your header.(unless you have some crazy header) So pick whatever size you want that is bigger than stock.

If your turbo, skys the limit. The turbine functions on a pressure ratio, (and a few other things not really concerning turbo back exhuast) meaning the higher the ratio, the faster spool up you'll have, hence faster acceleration.

pressure before turbine
-------------------------------- = your pressure ratio (PR)
pressure post turbine

The lowest post turbo constant pressure possible is atmospheric ~14.7psi ( or 0 psig). When you achieve that, then you have a big enought turbo back exhuast. If you want to go with the scavaging effect then go 1/4" smaller when you hit 0 psig, but you typically do not want more then 1-3 psig in a performace exhaust.

I know most of this is theory but it will give you an idea of what to look for.

Good luck
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