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The power gains/losses from the cat back are just a restriction thing, No real tuning can be done with them.

Has more to do with the muffler design and position in the pipe than the size, as long as its not choking the exhaust than run the smallest system you can, because its lighter and the few kg,s you save will mean more than 0.5kws

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you also have to remember that that article is about race headers where you generally won't have much of an exhaust after the headers, so some of those principles have to altered slightly. that is why it also makes no mention of power gains/losses from the exhaust system at all, but you will still get power gains and losses from catback systems

Actually, it does the exact same thing.

The headers are the BIGGEST gain you can make on an NA car.

After the first muffler/catalytic converter, the only difference you can get, is if you put a blockage in the exhaust. Go too big, exhaust gasses will cool though, slow, and cause a restriction.

As soon as you put a muffler/catalytic converter in, you lose the "pulsing" effect of the exhaust, once you lose the pulsing effect, you lose the ability to scavenge.

It is one thing to remember though, that the distance of the first muffler/cat converter from the end of the secondary join CAN affect performance. As you still have pulsing in this front section of pipe, you CAN tune the pulsing to scavenge the secondarys.

if you want to pop and flame decat or gutter your current cat run your car rich

whilst driving (car at operating temp) let off throttle then a second or two later tap the throttle and you will get bangs pops and flames

http://www.youtube.com/watch?v=01Of1-xyqZg

My exhaust on my N/A 33 it's got two hotdogs, stock rear muffler with a 3" tip

Will do a take off and drive by when i can i've never heard it outside the car so nfi how it sounds outside.

And excuse my bad shifting at times (i've hurt my knee while doing some downhill mountain biking)

what you may not realise is your car already has a rev limiter and it will make the bang bang bang sound on the limiter just like any normal skyline (or other car) does. just hold your foot on the accelerator and wait and it will hit the rev limiter and pop and bang away. not quite the same as a bee-r type igntion cut limiter but 80% of the 'fun' for none of the money.

it's a dumb idea but who cares? it's your car mate do whatever you want. having said that for the money of a bee-r limiter I can think of about 50 other things you could do to an NA R33 that are much more fun.

if you want to pop and flame decat or gutter your current cat run your car rich

whilst driving (car at operating temp) let off throttle then a second or two later tap the throttle and you will get bangs pops and flames

can someone build on this for me? the flames and the popping, i've noticed i can make the popping sound, but not that loud before. mostly when im driving constantly on a high speed, e.g 100+ and then let go of the accelerator and tap it. when i drove on 160ish and let go it made about 5 popping sounds together.

is there a way for me to get more pops or flame/sparks out of the car?

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