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If I put a straight through exhaust on my pretty much stock R33 Skyline for track days will this hurt anything ?? there will no cat and muffler.

Can someone tell me the advantages and disadvantages of this

Cheers

SirSkyline

I ran a straight through zaust on my old r33, only had 4 bends in the whole thing (1 turbo down, 2 bend to flat, 3 just past the cat(which was gutted), 4 just a small bend to get around the rear diff) and what I thought was a muffler was actually a bit of stainless steel welded around the pipe to make it look like a muffler.

Was VERY loud, apparently, well it was not drony or loud in the cabin.... :(

Anyway ran 7psi fine and ran 12psi with fmic fine, for 18mths.

Nope but I did have a SAFC installed and tuned.

Personally I would actually drop the cat and cat back off if I was going to the track, or go to any good exhaust shop and get them to make a small pipe with a bend it it to shoot the fumes out the side of the car and bolt it up to where the cat usually goes, then you'll get some noise!!!

Of course if you then decided to drive this on the road and get caught you would be in VERY big trouble, sounds absolutly hella good though! Revhead on here has a small pipe which he fits to his R33 with a PowerFC for track days, with his hybrid t3/t4 turbo, all you hear is that sweet high pitch whislte of boost once it comes on!

Oh and when I was running totally stock I dyno'd 132rwkw, then just after putting a cat back zaust on, no other changes, 2 weeks later at the same dyno I got 147rwkw.

Just goes to show just how much power can be gained by using the right exhaust system.

In the end with my pipe, pod, fmic, bleed valve set to 10psi and SAFC I got 177rwkw, not bad considering I started off with 132rwkw.

woldnt you be shooting flames though  :P

I guess you could get away with it if indeed you we able to do it discretely. However, it would be one loud car as you have discovered.

I would not be complaining one bit if it does shot flames. B) I might put a cat on it after the track day and see how we go for a while

I remember a while back when I installed my dump pipe that I accidently left a slight gap between the manifold that connected the turbo and dump. Result? the most awesome sounding noise from an RB engine, an added bonus was that is so friggn fast as well. Sorry, bit off topic. hehe

Does it have no cat at all...... hmmmm I have heard that no cat = HUGE fines :( when a cop looks under your car and see's no cat then there is a much high probability that you will get reamed. Best thing to do is to get a cat and gut it and whack that in, then at least it looks like there is a cat there to the cops.

Which can be easily changed for a proper cat + stock zaust to clear defects.

Side pipes are illeagal as they have no cat, and are freakin loud.

I'll take a pic of Revheads side pipe he uses for track purposes, it is louder than a 747!! Sounds awesome, but not worth the tens of thousands you might get in fines if pulled over.

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