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Lankstarr
12-05-2008, 07:02 AM
Hi guys,

I have my aftermarket exhaust on now and am very happy with how it sounds.

I would however like to experiment with what it sounds like with the decat pipes on. I think it will be too loud with both of them on so was considering trying it out with just one decat pipe to see if it gets me to the noise level I desire!

Are there any mechanical issues with just using 1 decat pipe? - I don;t want to screw anything up!

The car runs fine with both decat pipes on or off but I don;t know if it will confuse anything if just one is on!

Probably a stupid question!

Luke

NSX 2000
12-05-2008, 07:38 AM
Hi guys,
The car runs fine with both decat pipes on or off but I don;t know if it will confuse anything if just one is on!

Probably a stupid question!

Luke

I would of thought it would, as one bank of the V6 will be able to breath better than the other, but I'm sure Mark or Kevin will know more.
Paul.

Senninha
12-05-2008, 07:43 AM
Luke,

IMO, if your 'very happy' with the sound then stick with it and enjoy it! I was out on Saturday for a hoon and followed Leigh who runs without cats. Whilst is sounds like a race car soundtrack, it becomes tiring. Under all types of driving I could hear his exhaust over my own. Great if you want lots of attention but not so good if you want to calmly drive through town/normal traffic. If your NSX is going to resume daily use I would definately leave them in situ. Remember too that most track db's are high 90's so decatting would eliminate you from all track days.

regards, Paul

markdas
12-05-2008, 11:04 AM
I think its important to keep the flow from each bank of cylinders the same......it could create some uneven temperatures and and back pressures......I also agree that if you like the sound go with it!

What exhaust have you got fitted???

AR
12-05-2008, 01:40 PM
Just keep the test pipes on man!

NoelWatson
12-05-2008, 01:52 PM
Luke,

IMO, if your 'very happy' with the sound then stick with it and enjoy it! I was out on Saturday for a hoon and followed Leigh who runs without cats. Whilst is sounds like a race car soundtrack, it becomes tiring. Under all types of driving I could hear his exhaust over my own. Great if you want lots of attention but not so good if you want to calmly drive through town/normal traffic. If your NSX is going to resume daily use I would definately leave them in situ. Remember too that most track db's are high 90's so decatting would eliminate you from all track days.

regards, Paul

I wonder if high flow cats would be a good compromise

Lankstarr
12-05-2008, 04:02 PM
Thanks guys.

I'm considering high flow cats.

I have a larini exhaust fitted. It has been quietened down from when I had it put on originally as my car sounded like an F1 car (seriously!). With the cats on it is very manageable and doesn't sound much louder than OEM at idle (necessary as I live in a close).

I want to try different combinations for sound and managability and think it would be rude not to try the test pipes as I have them.

Based on the difference that test pipes made last time I think it would be a step too far so I might wait until I have sports cats before I start pi55ing around with it again.

I am enjoying the set up at the moment - it sounds great but I can;t keep my foot up dso the fuel consumption is terrible:laugh:

I don't think I'll be trying just one pipe as it sounds too risky!

thanks for the advice.

Luke

Lankstarr
12-05-2008, 04:03 PM
Just keep the test pipes on man!

I have neighbours to think about mate!

markc
12-05-2008, 08:45 PM
I can't see a problem with just running one test pipe provided you can fool the ECU to not throw CEL (Check Engine Lamp) or MIL (Multifunction Indicator Lamp) errors. Of course you'd have this same problem running both test pipes.

The standard exhaust mixes the exhaust pulses from both banks as do half of the aftermarket ones so that shouldn't be an issue. Even if you have separate boxes for each bank, one bank running more efficiently that the other won't cause a problem. Does your Larini exhaust mix exhaust pulses in a single silencer or have separate boxes like my Dali RR does?

Seems to be a reasonable idea to further "tune" the volume and quality of the exhaust note a little more, especially if you already have the test pipes :)

Cheers

Mark

AR
12-05-2008, 09:42 PM
Why don't you just have some samll mufflers made up to take the space of the cats?

Lankstarr
14-05-2008, 07:01 AM
I can't see a problem with just running one test pipe provided you can fool the ECU to not throw CEL (Check Engine Lamp) or MIL (Multifunction Indicator Lamp) errors. Of course you'd have this same problem running both test pipes.

The standard exhaust mixes the exhaust pulses from both banks as do half of the aftermarket ones so that shouldn't be an issue. Even if you have separate boxes for each bank, one bank running more efficiently that the other won't cause a problem. Does your Larini exhaust mix exhaust pulses in a single silencer or have separate boxes like my Dali RR does?

Seems to be a reasonable idea to further "tune" the volume and quality of the exhaust note a little more, especially if you already have the test pipes :)

Cheers

Mark

It mixes in a single box and I've had no issues with any lights coming on when running decat pipes.

I'd like to get sports cats made up, but whilst I have the decat pipes I would liek to play around with them a bit to see what different tunes I can make.

I'm really happy with the noise I have now - It's not far from standard when I start it up but once the car gets warmed up and I give it a boot it's really deep (as you'll see at Matt fest!)

Maybe I'll bring my socket set and jack and I can swap one cat over there to see what difference it makes:laugh:

Thanks

Luke

markc
14-05-2008, 04:13 PM
I can't make it to Japfest (work trip) :( but look forward to hearing your exhaust setup at some point soon.

I like my Dali RR but would ideally like a little higher pitch to the note. It's hard to describe but like many of the aftrmarket systems it's a bit too bassy and slightly flat. The Tiatec's and Paul's H&S are similar in this respect (I heard them all in anger at the TDI dyno day) but Leighs de-catted car shows that the Tiatec does get more screamy (as well as super loud) with test pipes :)

I can't justify the expense of another system when the one I have is as good as it is. The Dali RR is already plenty loud enough so I wonder if a single test pipe would give me that higher pitch. If you end up using just one maybe I could borrow the other one to test?

Cheers

Mark