Jump to content
SAU Community

Recommended Posts

GDay,

Im in the process of putting an RB26 in my R32 gtst. Its a full rebuild engine with all the forged stuff and a single 700hp garrett high mount turbo. The guy who has done the engine work, and who will be modifying the exhaust, has recommended a new 3.5inch exhaust. I currently have a stainless 3inch turbo back system which cost around $2000. I dont want to upgrade if its unneccessary.

My question is:

Will a 3inch exhaust be sufficient for around 350rwkw maximum?

If not, is four inch better?

I have been told (and read) that anything greater that 3inch is overkill. Is this correct for my application?

Any advice from people with first hand knowledge in this area would be appreciated.

Shaun.

Try the one you have ATM it shouldnt be throttling/choking the engine. my freinds car just dyno'd 394rwkw with a 3" exhaust its a rb30det with a big single KKK turbo.

Then he took off the cat and put a straight thru pipe and dynoed 412rwkw!

you cat might hold you back but the exhaust will prob be fine for your application

My GTR R33 has been dynoed at 412awkw and I have a 3" exhaust system.

The thing is when I removed the external wastegate pipe to be plumped out to atmosphere I picked up another 5kw.

This is using a straight through pipe as my cat which was also at 3" but I am now ungrading to 3.5" system as there is more power there.

There are no gains above this and the outlet on the turbo would be no greater then 3.5" so there is no point in going any larger.

Your exhaust system is as big as the smallest point in the system.

I don't want to to this as well as I am so very happy with the way my car sounds and don't want to lose it but the extra power is just sitting there doing nothing....

The following modifications are as follows:

RB26 ENGINE

HKS 88MM FORGED PISTONS

HKS CON RODS

HKS STEP 2 280 CAMSHAFTS

HKS CAM GEARS

HKS 1.6MM HEADGASKET

JUN OIL PUMP

PERFORMANCE METALCRAFT 8L RACING SUMP

PORTED HEAD

NISMO BEARINGS

NISMO CAMBELT

AUTRONIC SMC AND LOOM

1000CC INJECTORS

BLITZ FUEL RAIL

MALPASSI FUEL REG

SPLITFIRE COIL PACKS

GARRET BALL BEARING TURBO(NEW T04Z) - RACEPACE CUSTOM

RACEPACE CUSTOM EXHAUST MANIFOLD

TRUST EXTERNAL WASTEGATE

NISMO G-MAX TWIN PLATE CLUTCH

HKS GT SPEC DRAG INTERCOOLER

CUSTOM FUEL SWIRL POT - TWIN OUTLETS FED BY GTR FUEL PUMP

2 X BOSCH 044 EXTERNAL FUEL PUMPS

HKS OIL COOLER KIT

TRUST EXHAUST 3"

ARC ALLOY RADIATOR

ARC OIL CATCH TANK

HKS EVC4

HKS COLD AIR INTAKE

TUNED BY BEN @ RACEPACE MELBOURNE

CURRENTLY MAKING 417KW@THE WHEELS AT 1.3 BAR

WAS MAKING OVER 500KW WITH PREVIOUSLY FITTED HKS T51R

Cams make the engine lumpy like a V8 but it's idle is awesome.

I don't find any faults with street driving at all, has good power off boost and loooovvvves to rev and pull's hard all the way to redline @9500rpm.

Like to see if I pik up more power with a 3.5" exhaust, I think there is some left in it..... well just have to see

Generally a 3.5" is required up over 300rwkw to be 'optimal'.

I want to keep the noise down so I will be going a 3.5" dump in to a 3.5" cat, then a 3.5" pipe in to a intermediate muffler that splits the 3.5" in to 2 x 2.5" pipes, 2.5" pipes to the rear of the car where there is another large muffler, 2x 2.5" tips out of the muffler.

It will flow really well, not drone and sound quite nice. :D

Its very similiar to the XR6 APS exhaust system.

Generally a 3.5" is required up over 300rwkw to be 'optimal'.

I want to keep the noise down so I will be going a 3.5" dump in to a 3.5" cat, then a 3.5" pipe in to a intermediate muffler that splits the 3.5" in to 2 x 2.5" pipes, 2.5" pipes to the rear of the car where there is another large muffler, 2x 2.5" tips out of the muffler.

It will flow really well, not drone and sound quite nice. :D

Its very similiar to the XR6 APS exhaust system.

Hey cubes, this is a clever way of reducing the noise and still keeping the noise levels down....I like it :D

Q. How would a HKS Super Dragger Exhaust sound (3.5" straight through) on a built RB26?

This is what I was thinking of doing when I replace my 3" system to a 3.5" system.

Weird thing is I have a 3.5" system to the cat then 3" system to the rear :microwave

i'm not sure how the Super Dragger would sound.. Obviously loud.

My goal was to make the exhaust look fairly standard out the rear and sound as quiet as possible with no drone inside the cabin. The large intermediate muffler was the only way to go with 2 x 2.5" pipes.

Apparently a single 3.5" does flow better than 2 x 2.5" pipes but it is much louder.

  • 3 weeks later...

Ive just sold my 3 inch exhaust in favour of going to 3.5. Can anyone recommend a japanese brand exhaust that has the following features?:

• Stainless steel

• Sits nice and close to the body. Ive heard that some jap exhausts hang down too low.

• Isnt offensively loud so that it attracts cops.

Also, if anyone has info relating to where i can get such an exhaust, can you let me know?

Any feedback would be appreciated.

Thanks,

Shaun.

0414972596

I would highly reccomend a Trust TR (they are 3.75 inch i think) they fit the bill for your requirements except for the stainless steel part which is really nothing major. The silencer system they have is very effective and they make room for large power increases.

Advan Perfromance in Silverwater stock them - 9647 1326

IMO a japanese car needs a new japanese exaust.

Believe it or not but japanesemotorsport have much better prices on the trust exausts. I think mine was around 1200 delivered(2years ago), took me minutes to install, not much louder than stock at idle, great note, no drone, etc, etc.

Do not commit the sin of the australian made catback system., it will look and sound like shite, not to mention being the japanese ones are typically designed on CAD software.

Support local front/dump pipes instead!!!111@2

For look, sound, performance you cant go past a japanese system, stuff the price :wassup:

Support local front/dump pipes instead!!

Ha Ha, Funny sh1t! Thats exactly what im doing. Ill give JMS a ring, but if im gonna pay the dollars i think i want stainless. I might look into Apexi.

Guest two.06l
Support local front/dump pipes instead!!

Ha Ha, Funny sh1t! Thats exactly what im doing. Ill give JMS a ring, but if im gonna pay the dollars i think i want stainless. I might look into Apexi.

Give Peter a ring at Advan, they get some great TRUST front pipe copies made up...you would be hard pressed to tell the difference!

P.S. why do you want stainless?

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • To follow up a question from earlier too since I had the front bar off again (fking!) This is what is between the bumper and the drivers side wheel And this is the navigator side, only one thing but its a biggy! So basically....no putting coolers in the wheel arches without a lot of moving other stuff. Assuming I move to properly race prepping this car I'll take that job on and see how the computers respond to removing a whole bunch of ADAS modules
    • So I prepped the car for another track day on Wednesday (will be interesting to see coolant temps post flushing out and the larger reservoir, with a forecast of 3-14 being 20o cooler than last time I took it out). Couple of things to mention; since I am just driving the car and not taking a support vehicle, I took the rear seats out and just loaded the back up Team Trackday style. Look at all that space! To cover off removing the rear seat....it is weird (note the hybrid is probably different because it wouldn't have folding rear seats) Basically, you remove the lower seat base, very similar to a r series but it is a clip that pulls forward to release the base rather than it being bolted down. Easy Then, you need to remove the side section of the rear seat on each side. There is a 14mm head nut at the bottom of the side piece, the it slides upwards off a hook at the top to release; you also need to unhook the seatbelt from the loop at the top. Then the centre piece is weird. You need to release/fold the seats forward with the tab in the boot on each side From there, there are 2,x12mm headed bolts holding the rear of each seat to the folding bracket, under the trim between the rear seat and the boot (4x christmas tree clips there, they suck). The seat is out but you can see where the bolts attach to the bracket
    • As discussed in the previous post, the bushes in the 110 needed replacing. I took this opportunity to replace the castor bushes, the front lower control arm, lower the car and get the alignment dialled in with new tyres. I took it down to Alignment Motorsports on the GC to get this work done and also get more out of the Shockworks as I felt like I wasn't getting the full use out of them.  To cut a very long story short, it ended up being the case the passenger side castor arm wouldn't accept the brand new bush as the sleeve had worn badly enough to the point you could push the new bush in by hand and completely through. Trying a pair of TRD bushes didn't fix the issue either (I had originally gone with Hardrace bushes). We needed to urgently source another castor arm, and thankfully this was sourced and the guys at the shop worked on my car until 7pm on a Saturday to get everything done. The car rides a lot nicer now with the suspension dialled in properly. Lowered the car a little as well to suit the lower profile front tyres, and just bring the car down generally. Eternally thankful for the guys down at the shop to get the car sorted, we both pulled big favours from our contacts to get it done on the Saturday.  Also plugged in the new Stedi foglights into the S15, and even from a quick test in the garage I'm keen to see how they look out on the road. I had some concerns about the length of the LED body and whether it'd fit in the foglight housing but it's fine.  I've got a small window coming up next month where I'll likely get a little paint work done on the 110 to remove the rear wing, add a boot wing and roof wing, get the side skirt fixed up and colour match the little panel on the tail lights so that I can install some badges that I've kept in storage. I'm also tempted to put in a new pair of headlights on the 110.  Until then, here's some more pictures from Easter this year. 
    • I would put a fuel pressure gauge between the filter and the fuel rail, see if it's maintaining good fuel pressure at idle going up to the point when it stalls. Do you see any strange behavior in commanded fuel leading up to the point when it stalls? You might have to start going through the service manual and doing a long list of sensor tests if it's not the fuel system for whatever reason.
×
×
  • Create New...