3.0RB system

[team_subaru]

I have just put a X-force SS Catback exhaust on the our 3.0RB..

Not is pretty good without being loud and obnoxious and pretty quite on idle..Will have DYNO figures next weekend so will be able to see if there has been any performance gains...

System cost me $900.00 fitted

[bigamph]

Does anyone know if K2 Gear Spec Neo's off a 2.5 will fit on a 3L????

[castek]

pipe should be the same mate, only difference is wagon and sedan mufflers are different lengths.

[bigamph]

pipe should be the same mate, only difference is wagon and sedan mufflers are different lengths.

Cheers mate!

hmmm, food for thought....

[zoidberg99]

I have just put a X-force SS Catback exhaust on the our 3.0RB..

Not is pretty good without being loud and obnoxious and pretty quite on idle..Will have DYNO figures next weekend so will be able to see if there has been any performance gains...

System cost me $900.00 fitted

hey mate, can you post up some video so i can get an idea for how it sounds...

[c0en]

I have just put a X-force SS Catback exhaust on the our 3.0RB..

Not is pretty good without being loud and obnoxious and pretty quite on idle..Will have DYNO figures next weekend so will be able to see if there has been any performance gains...

System cost me $900.00 fitted

hey mate, can you post up some video so i can get an idea for how it sounds...

Yes please upload a clip. In need of some 3.0RB exhaust inspiration.

[bradsm87]

I'm just about to make an exhaust on mine. A few findings:

The factory exhaust goes from twin 2.25 (necked down to less than 2" in a few spots) into a single 2.125" then into twin 1.75. Exhaust gas does cool as it makes its way to the rear and doesn't require as big of an exhaust the further back it gets but I think from factory, they have taken this TOO FAR!

the 2.25" out of the headers is too big IMO and ruins the scavenging of the exhaust gas. Also the 3 factory cats completely stuff up the scavenging of the exhaust gas. These 2 things mean the engine has to PUSH the exhaust gas out harder when it could have a bit of help by being drawn out by the momentum of the downstream exhaust gas. After coming out of the big twin 2.25 pipes, it gets choked into a single 2.25 system.

My plan is to cut off the factory exhaust after the headers and run twin 2" pipes (smaller than factory) into a single 2.5" (larger than factory) all the way to the back with a single 2.5" straight through muffler at the back. Not splitting the exhaust in half will always mean less restriction. Also it's way too hard to find good quality true 2" straight through mufflers that would be good for a twin system. Everything decent that's available in Aus starts at 2.5". I'll put a single metal high flow cat after the twin pipes merge. This means the pulses in each of the twin pipes directly out of the headers don't get wrecked by having cats in there. No, it won't comply with Euro IV emissions any more but it'll still have a cat that does a good job and produce a hell of a lot less emissions than 95% of cars out there.

I've been trying to get the lowest average L/100km possible over the last couple of tanks and the best I've got is 10.6. I'm confident that with the new exhaust, I'll be able to get 10.2 easily and noticeably more power throughout the revs.

[bradsm87]

I finished the exhaust. I'm mostly very happy with it. The twin 2" from the headers to a Very smooth merge collector is SO much better than the 3 cats and constantly changing pipe diameter. The single high flow cat now sees the merged pulses from all 6 cylinders instead of having 1 in each pipe to ruin the strong 3 cylinder pulses. All this means for emissions is that the cat takes longer to heat up when cold.

It sound nice and quiet (nearly silent) on idle, cruise and decel and it moderately loud on throttle. There is a light annoying rasp sound that is very common to 6 cylinders between 3000 and 4000 rpm on full throttle. The warmer the engine is, the quieter it gets. I've done heaps of research on it and it seems to be caused by the gas slowing down too fast coming from the TINY 1 3/8 factory primaries into the 2" secondaries as well as the gas cooling down which also has a slowing effect. I'm gonna try and heat wrap the secondaries and see if that helps.

I dunno about power yet until I disable a couple of CEL codes and can actually use sports mode. Fuel consumption is WAY better. Before, the best average I could get if I REALLY babied it was 10.4l/100km. Now, I have no problems getting a constant 8.6-9.2 and that's normal driving, not trying as hard to get a good average!

[I Wish]

There are only two cats in the oem system.

[Doyab]

There is 3.

[Robbks]

There is 3.

correcto
one in each exhaust header and a third IS the 2->1 joiner

I dunno about power yet until I disable a couple of CEL codes

that's the reason i'm ripping out 3 the stock cats and using one high-flow (200cell) in each header and leaving all 4 o2 sensors in their stock location on each end of the cats.

[bradsm87]

There is 3.

correcto
one in each exhaust header and a third IS the 2->1 joiner

I dunno about power yet until I disable a couple of CEL codes

that's the reason i'm ripping out 3 the stock cats and using one high-flow (200cell) in each header and leaving all 4 o2 sensors in their stock location on each end of the cats.

U'll still get a cat related CEL with a 200 cell i reckon. The new stuff is SO sensitive. Changing diameter and introducing a restriction that close to the headers is pretty bad for performance IMO.

[I Wish]

Wow I just checked the manual, you are correct. For some reason I always thought that the one at the "Y" was just a muffler.

My Apologies.

[Robbks]

U'll still get a cat related CEL with a 200 cell i reckon. The new stuff is SO sensitive. Changing diameter and introducing a restriction that close to the headers is pretty bad for performance IMO.

stock cats are something stupid like 400cpi
the ones i'm using are only 200cpi, so they will flow a lot more for the same diameter.
But i'll step them up to 2" in/ out then into 2" collector
so there's going to be much less restriction than stock.

my tuner has indicated that there will be no issues
IIRC the front 02 sensor is the wideband and rear is just the generic narrow-band.

[I Wish]

IRC the front 02 sensor is the wideband and rear is just the generic narrow-band.

Can you confirm this?