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Hey Guys,

Just got a couple of questions about my current exhaust system on my R33 gts-t.

I have a 3inch turbo back but its not exactly "ALL" 3 inch back.

From the turbo, there is a piece about 20cm long that isnt 3inch that is part of the dump pipe. and it appears to be the stock pipe.

If you look at the picture, i have indicated where my 3inch exhaust starts from (Note: picture is not my exhaust its just an example)

post-23613-1210750535_thumb.jpg

After looking at my picture, i have a few questions about my current setup:

Is this stock piece restricting my 3 inch system. If so, by how much? And should i replace it with a 3" split dump/front pipe?

Is a split dump/front pipe roadworthy and "street legal"

Im sure many of you will be able to provide me with advice and the assistance i need :O

Thanks

Edited by Ricos
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https://www.sau.com.au/forums/topic/219200-my-exhaust-system-need-helpopinions/
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Hey Bud

1. Any part of the exhaust which is smaller than another part, i.e. 3" pipe into 2" pipe, is restricting flow.

2. Yes the split dump and front pipes are legal and well worth getting

It would be a great investment to finish off the exhaust system with a 3" front/dump pipe.

Hope this helps

Hi Rick.

I made 200rw/kw with the stock dump but i would replace it anyway if you can. I just put in a JJR split dump pipe from just jap (cost about $80 i think).

Yes they are street legal, as long as the exhaust is under 90db which will have more to do with your muffler setup rather than the front/dump pipe.

I was stumped when i saw it.

The whole exhaust is 3" except that part. It was like that when i bought it. Why would someone do the exhaust and not change that part and leave that peice stock. Wierd

If i get a new split dump/front pipe, do i need a highflow cat?

I dont no if my current cat is stock or not :S is there any way to tell ?

Thanks for the help so far guys!!

Edited by Ricos

Could i get away with just replacing the dump pipe?

something like this (JJR Split Dump Pipe)

http://justjap.com/store/product.php?produ...=276&page=1

OR

would it be better to replace with this (JJR Split Dump/Front Pipe)

http://justjap.com/store/product.php?produ...=276&page=1

i have read that the JJR dump/front would be better because the wastegate joins lower down the dump, thus minimising turbulence and also, the all in one has less restriction cause there is no flange joining the dump to the front pipe? Are these comments true.

Just trying to work out the better option :O

Thanks

Edited by Ricos

that whole section from turbo to cat in the pic is the stock exhaust.

there is nothing there that is 3 inch .

the stock exhaust is around 2 1/2 inch which is what you have there.

is the rest of your exhaust the same as that?

if so its just a stock system.

thro the lot in the bin and get a propper 3 inch or bigger exhaust from turbo back.

i have probably confused every one

The only stock part on my exhaust is my dump pipe....Everything else is 3inch (frontpip, cat, catback etc...)

As mentioned above that picture was only to demonstrate which remaining part was stock....Its not my actual exhaust

The only thing im missing from my 3" exhaust system is the dump pipe. My dump is still stock for some unknown reason (was like that when i bought the car)

So my question is now whether to replace the dump with a 3" split dump or to replace it with a combined split dump/front pipe (and get rid of my exsisting 3" front pipe)

http://justjap.com/store/product.php?produ...=276&page=1

VS

http://justjap.com/store/product.php?produ...=276&page=1 ----- with the 3 inch front pipe i already have

Apparently the split dump/front pipe is better because the waste gate drops into the front pipe rather than back into the dump. Which cause flow restriction and turbulence.

Just need someone to enlighten me if this is actually an issue or not ? and if so...how much would it restrict flow...

sorry if i have confused every one

Edited by Ricos

I know its a bit more expensive, but I would suggest the batmbl/BOS Split Dump/Front Pipe

http://www.skylinesaustralia.com/forums/Ba...it-t136607.html

http://bosimporting.com.au/index.php?page=...t&Itemid=27

I just got mine today.

I chose this over the JJR one, as the waste gate pipe doesn't come in on the bend (like the JJR one) it comes in afterwards.

But many people think the JJR one is just as good , and obviously the cheapest option is just the get the Split Dump Pipe (- Front).

Edited by Az_StrYdeR

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