Jump to content
SAU Community

Recommended Posts

Hi all,

I'm looking at getting the quietest exhaust possible while still managing around 200rwkw or slightly over.

Every exhaust I have seen on 33's is to loud (over 87db).

As my 33 is my daily I want to keep it as quiet as possible while still gaining some benefit from having an aftermarket Dump/front pipe and a highflow cat.

I was thinking of just leaving the stock cat back portion of the exhaust but with an after market dump and highflow cat.

Would this still be highly restrictive?

My understanding is that the most restriction on these systems is the dump and cat but not so much the rest of the system.

Thanks.

Link to comment
https://www.sau.com.au/forums/topic/443635-stock-cat-back-power-limit-r33-gtst/
Share on other sites

I agree with nizmo_man. You can have a decent flowing exhaust that isn't over the top loud by using proper mufflers.

This idea that unless it's a 3.5" straight through with a decat means it won't flow for shit is complete bullshit. You can have a 3inch exhaust from the dump to tailpipe with decent mid and rear mufflers (no cannons) and still perform well while being quiet.

I guess what you percieve to be quiet is down to personal preference. Also the stock catback is the cheapest option if that suits you; just wanted to throw in the idea that you can have a decent performing system without it being obnoxiously loud.

Having said that it would be pretty hard to pass the EPA noise test with anything bigger than the stock system I imagine, hopefully someone can weigh in here

I guess I just don't want to spend mega bucks on a system if the stock cat back system is still good enough with an aftermarket dump/cat combo. If I was chasing 300rwkw or something then fair enough, but I think I'll be staying with the stock turbo for awhile.

I think you're missing the point. There is no "power limit" for the stock cat-back. You can flow any amount of "power's" worth of exhaust through it you like. It's just that as you get up into bigger flows it starts to put up more of a fight and the backpressure mounts. At some point you would be silly to continue winding up the boost and doing whatever other mods to the engine to make it able to push that extra gas through the exhaust. But long before that point you would be well advised to upgrade the exhaust to something larger because it is basically free power and free boost response (compared to bigger turbos and all the other stuff you can buy to strap on to the engine). A good exhaust is not that expensive and will immediately allow the engine to make more power and boost faster even with nothing else changed. To ask if it is "good enough" for 200rwkW ignores the fact that if you leave it on and try to make 200rwkW you will need more boost and use more fuel, possibly run closer to detonation, need more conservative timing, etc, than if you were to put a bigger exhaust on it.

In reality, the correct order of modification for a turbo engine is almost always exhaust first, everything else second.

^ That's very true.

I wasn't arguing what's better or what was achievable, I know the stock system is restrictive and not ideal, but for all I know the stock cat back portion flows ok for a stock system and could be fine for the stock turbo boosted etc.

I'll keep an eye out for a decent second hand system, something without a canon.

Cat back exhast only will make it hard to get around 200kw mark, I have a full 3" turbo back xforce system on mine and noise when cruising is no problem at all even with the added drone of having a wagon.

Definitely keep an eye out for a 2nd hand system and just make sure the mufflers are in good nick so you can minimize noise but still have no problems with restriction in the exhaust.

As others said rather than screwing around trying to fine tune everything with various mods just go exhaust first to have good starting point to see what mods you need rather than going all out on a restricted exhaust.

Sorry for the essay and any typos which I am prone to with lack of proof reading

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

    • It is a kunfine Android screen . Does anyone know the wirering diagram of the fuga ??
    • just an update to this, poor man pays twice  Tried sanding down the pulleys but it didnt do the trick. Chucked another second hand alternator in the na car which I got for free off my mate and its fixed the squelling. Must have been unlucky with the bearings.    As for my turbo car, I managed to pick up a cwc rb alternator conversion bracket + LS alternator for 250 off marketplace, looked to be in really good nick. Installed it , started the car and its not charging the battery.... ( Im not good with auto elec stuff so im not sure if this was all I needed to do but I verified such by using a multimeter on the battery when the engine was running and I was only getting 12.2v )   I had to modify the earth strap for the new LS alternator , factory earth strap was a 10mm bolt which did not fit the bolt on the LS alternator which was double the size so I cut it off , went to repco bought some ring terminals that fit, crimped it onto the old earth strap and bolted it up to the alternator , started the car and same issue. Ran like shit and was reading 12.2 at the battery.  For a "plug and play" advertised kit thats not very plug and play but alas.  My question is , am I missing something ? Ive been reading that some people recommend upgrading the stock 80 amp alternator fuse to a 140 amp but I dont see how that would stop the alternator charging especially at idle not under load.  Regardless ive pulled it out and am going to get it bench tested by an auto elec tomorrow but it would be handy to know if ive missed something silly or have done something wrong.   
    • My wild guess is that you have popped off an intake pipe....check all of the hoses between the turbo and the throttle for splits or loose clamps.
    • Awesome, thanks for sharing!
    • To provide more specific help, more information is needed. What Android screen? What is its wiring diagram? Does the car's wiring have power at any required BAT and ACC wires, and is the loom's earth good?
×
×
  • Create New...