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decided to get a custom 4" exhaust made of for the car to aid further mods and was wondering if anyone recomended any shops in melbourne that will do a good job.

i know nismoid u had one made right? if ur not in a shit mood and u feel generous enough to point a flame thrower lover in the right direction that be great :D

any help appreciated from fellow sau'ers

Edited by R34NRG
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no workshop will do 4" for you

only the jap stuff comes in 4"

the best thing i can recommend is get a split dump pipe or a bellmouth dump

get a good jap brand or locally made one - say like the BATMBL split dump 3" is spot on

and then take it to an exahust workshop and say fit this and give me a good high flowing 3" cat back exhaust

and make sure you get a new high flowing cat too

if you goto your average exhaust place that hasnt done shitloads of skyliens they might not be able

to match up the dump / exhaust flange on yhe stock turbo, so choosing one of the pre-fabricated dumps saves times/hassles

i took mine with a batmbl split dump to glenroy performance exhausts in truck city / near epping

they charged me $750 to fit my supplied pipe and supply & install a 3" cat back system

came out nice, good job, spot on, did it ahead of schedule too.

I'd recommend talking to a workshop about your "future works" before you go and spend money on things you may not require :D You really need to get some plan of what your looking to achieve before you just randomly buy parts. Sounds to me like you have money burning a hole in your pocket.

That plus the fact I don't know any skyline running a 4" system, 1 they wont fit of the turbo, 2 I don't see it being necessary. I also run a BATMBL 3" front/dump and it's tops. With a special cat and a decent 3" system you'll be more than fine, ask any tuner.

Just get a secondhand jap exhaust, any ex-gtr will be around 4' anyway. By the way, look what we've got for you this time boy...........

15b_FlameThrower_lge.jpg

hahahaha good one knackers

Try fitting one of these lil puppies...there all the rage in japan...well when i was there years ago they were...heres a pic i took at USS :thumbsup:

gallery_2711_155_30168.jpg

Places will do 4" Paul/Adz, no problems there, just a pain to get the 3-bolt flanges/weld/fit etc.

I had 3.5" made no problems :thumbsup:

Pretty pointless though as it makes the dump useless (has to be flared from 3") and throw-away item if you get a T88 later.

So better off to just go 4" from the cat-back.

Hence most jap items that are 4", are all cat-back items as the dumps are always custom due to fab'd manifolds/turbos and so on.

I aint saying where mine was done though. I wouldnt bring that upon the poor person to have to deal with you.

You'd be very surprised what a 3 inch pipe will flow.

Short of a T88 or something similar you wont really need anything bigger than 3"

Think of it this way, the exit of the turbo is the most restrictive part of the exhaust before you get to mufflers. Hence, match the size of the outlet of the turbo (maybe plus a little bit to turbulate the gasses) and then run the least restrictive turbo you can.

A lot of VERY high power GTRs are running 3 inch pipes.

atm im running batmbls dump/front pipe with the 3" catco cat that he sells with a 3" blitz nur spec R catback.

just feels restrictive for some reason i dunno, maybe its just me.....but i drove my mates 34 which has a full 4" exhaust, and the thing felt like it could give more and more.....

cant explain it but yeh

i just assumed a 4" will perform alot better then a straight 3". theres gotta be some back pressure of some sort, so logic only tells me go bigger?

Edited by R34NRG
take off the dump pipes and stick your eye up the exhaust side of the turbo, ull be able to spot any restrictions easily then !

goto stick your head real close though

ever since i replaced the exhaust sytem to stock to clear a defect its been real restrictive, im thinking maybe it might just be that.

im thinking about also going catless, yeh yeh yeh i know stfu wingers

Edited by R34NRG
You'd be very surprised what a 3 inch pipe will flow.

Short of a T88 or something similar you wont really need anything bigger than 3"

A lot of VERY high power GTRs are running 3 inch pipes.

3.5" you'll find most of them are Pete, not 3".

I would strongly disagree a 3" exhaust can flow upto a T88, infact a lot less.

I had issues with my 3" flowing ~300rwkw around that back when i had my RB25 setup on there, and i know of other cars as well in similar situations

Example, a GT-SS equipped RB26 that comes to mind that (without race fuel) would not have made 330rwkw due to having a 3" exhaust, the size is class restriction for certain types of racing... With the exhaust it would make more power.

I intend to back this up (being our two motors etc are virtually identical) by making the same power on PULP/3.5" rather than R.Fuel/3" :thumbsup:

From my own toy'ing around with 300+ i go by this.

3" = 300rwkw

3.5" = 370-400rwkw

4" = 400rwkw+

Less restriction the better, but no point going bigger than you need to, it just costs more money for no real gain

3" = 300rwkw

3.5" = 370-400rwkw

4" = 400rwkw+

hrmmmm i guess that chart makes sense but why spend the extra cash getting a 3", getting rid of it later for a 4" when u can spend pretty much the same amount in the 1st place for a 4" thats more high flowing then the 3" at the start

mmmmmmmmm..........lol sounds right

fair argument in saying that there is no "real" gain, but im sure it will come in handy

Edited by R34NRG

I happen to know a car that went BACKWARDS when going from a 3" to a 3.5 inch.

anyway, I repeat, the smallest part of your exhaust is the most restrictive. Be that your dump, a flange, bad muffler etc.

My Fujitsubo Power Getter was 3" from the cat to the second section where it flared up to 3.5 inch. My reasoning is that the most restrictive part of the exhaust is the first section where it is 3", and where the gasses are "biggest and hottest". I changed the rear section to a 3" muffler and I dropped about 8dB, made my car legal and it still made the same power as before.

Doesn't mean I don't put on my big pipe for when I want it loud though :)

just feels restrictive for some reason i dunno, maybe its just me.....but i drove my mates 34 which has a full 4" exhaust, and the thing felt like it could give more and more.....

some thing tells me that maybe your mate has thought his mods out a bit better than you have.

ever since i replaced the exhaust sytem to stock to clear a defect its been real restrictive, im thinking maybe it might just be that.

ya think?

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