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Stock Exhaust Performance - Gains?

bombastic
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bombastic Collaborator

bombastic

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After writing off my first R33 (lesson learned, I won't do it again, promise!), I'm looking at another... I tried other cars but just keep coming back to the R33 :)

Anyhow. Have driven a few and some had the stock exhaust, I really liked the sound of it, so quiet.

I'm just wondering if I bought one and decided to keep the stock exhaust, what mods are worth doing? I've still got a powerfc from my old car, but I'm just wondering whether there will be much gains to be had in having it tuned? With say, an R34 SMIC and 10-12psi.

Or maybe there is a more free-flowing alternative available which doesn't add noise?

Sorry if this has been covered before, I searched for "stock exhaust" and didn't turn much up.

Cheers!

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BAMR33 Mentor

BAMR33

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Posted (edited)

Yeah, I actually think the stock system sounds really good too. But if power is what you want it has to go, as far as noise goes you don't have that much of choice because aftermarket manufactures obviously design them to be louder for that sportier sound and better flow. What you could do is buy a decent 3" system off greenline.jp and add another resonator to reduce noise.

Edited by BAMR33
eMsta Grand Master

eMsta

Posted
Posted
After writing off my first R33 (lesson learned, I won't do it again, promise!), I'm looking at another... I tried other cars but just keep coming back to the R33 :)

Anyhow. Have driven a few and some had the stock exhaust, I really liked the sound of it, so quiet.

I'm just wondering if I bought one and decided to keep the stock exhaust, what mods are worth doing? I've still got a powerfc from my old car, but I'm just wondering whether there will be much gains to be had in having it tuned? With say, an R34 SMIC and 10-12psi.

Or maybe there is a more free-flowing alternative available which doesn't add noise?

Sorry if this has been covered before, I searched for "stock exhaust" and didn't turn much up.

Cheers!

change the front/dump, and put a bigger cat - i think that would be a good start. I got the front/dump, large cat and the trust pe2 cat back...good performance gain, very quiet too. dynoed at 164rwkws at re customs.

get a front mount - just jap (for around 400), second hand apexi power fc ecu, tweek turbo to around 11psi - get a full tune. not sure what the power rating will be like though.....

someone can correct me if im wrong with those mods......(probably dont need the power fc - but most people have it)

Spook's_Skyline Mentor

Spook's_Skyline

Posted
Posted

i discovered a quiet exhaust is a pretty large restriction

i went from a stocko, to a blitz jobby with an extra muffler

was quiet as (missus request) but robbed me of a fair bit of power (around 30rwkw)

cheez Mentor

cheez

Posted
Posted

im running a 3" straight dump pipe, hi flow cat, and jasma approved cat back exhaust, its like 92dB on back off and 90dB on ramp up, has also a mid muffler and i had my sky tined last week at 168rwkw. only other mods are fmic, k&n panel filter and grounded out boost solenoid at 8psi. runs well enough.

guy i got the exhaust off said he had it tuned on his car and with it was still making 198 at the rears. IMHO, epa should go get fuc*ked. leave us to modify how we like as long as our pollution emissions are fine and the mods are rw. who cares if its a lil loud. ecu, pod, fmic, boost, wats it got to do with em. bloody poofters.

Kinks Grand Master

Kinks

Posted
Posted
im running a 3" straight dump pipe, hi flow cat, and jasma approved cat back exhaust, its like 92dB

good for you, but your opinion is irrelevant here. 92dB is a long way from being quiet, in fact 84dB is the cutoff for continuous exposure without hearing damage. if you want to beat your chest about having a loud exhaust find somewhere more suitable.

  • 2 weeks later...
bombastic Collaborator

bombastic

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  • Author
Posted (edited)
Fujitsubo make excellent exhausts for what you are after. They are quiet at idle and at cruise and have a decent sound when on full song.

My old R33 ran a Super Ti from memory, was great.

Thanks I will look into that.

I'm going to see if I can get the exhaust off my wreck and repair it. The front pipe and cat looked fine, but the catback was dented and the muffler a bit squashed... don't know how much it's going to cost me. Might have to replace the muffler altogether?

Is there much point just putting split dump/front pipe + hiflow cat on? Might free it up a bit without being noisier.

good for you, but your opinion is irrelevant here. 92dB is a long way from being quiet, in fact 84dB is the cutoff for continuous exposure without hearing damage. if you want to beat your chest about having a loud exhaust find somewhere more suitable.

Any idea how many dB a stock exhaust system would be?

Edited by bombastic
  • 2 weeks later...
pixel8r Mentor

pixel8r

Posted
Posted
good for you, but your opinion is irrelevant here. 92dB is a long way from being quiet, in fact 84dB is the cutoff for continuous exposure without hearing damage. if you want to beat your chest about having a loud exhaust find somewhere more suitable.

I think you're confusing something here - 92dB would be OUTSIDE the car, probably measured near the exhaust?

For a free-flowing exhaust thats still fairly quiet (sometimes inaudible when cruising at 50-60), make sure you get 2 mufflers, no resonators or anything. I've got a 3" oval magnaflow muffler at the rear and another 3" oval muffler in the middle. Being a wagon I need it quiet to reduce drone!

Its definitely quiet enough but not as quiet as stock.

To make it quieter and still get good flow, use twin pipes...although this will cost more.

It seems you either get good power, or a whisper quiet exhaust, but not both. Also I wouldn't bother doing other mods when you have the stock exhaust, except maybe just an SAFC or something - to maybe save a bit on fuel? Other than that, be aware that adding more boost pressure (ie. more psi) will likely just put more stress on your turbo without actually flowing more air through your engine (it could actually flow less!). psi is a measure of pressure, not necessarily airflow. :D

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