Borla exhaust lesson update

[red rider]

Took the car this am to the muffler shop, they put it on the lift, checked out the fact that if has essentially 4 mufflers and told me it's likely Suzuki realized there would be droning issues with this car. They advised anything that I did to it would increase the noise and drone. He told me if you value the quiet which I do, just let it be. I thanked him for his honesty and candor, lesson learned.

[Wonson92]

Have you conisdered just doing a bi-modal/butterfly valve muffler kit? X-force in Australia do a line of products called varex. Ive had some experience with x-force on my best friends car, im assuming theres similar over seas though.



On an STI:


Not the best example given the choice of car but theyre supposed to be quieter than a stock exhaust on 'silent'

[murcod]

Interesting response from them- especially suggesting Suzuki recognised there was a potential drone issue! Most new vehicles have hugely restrictive exhaust systems and as many mufflers as possible crammed underneath. Given the market they were pursuing with the Kizashi, it stands to reason Suzuki would try and keep the interior noise levels to a minimum.

PS: I can't help but wonder why you were looking at changing the system if you value keeping the exhaust noise down?

[red rider]

I suppose I wanted the best of both worlds, a more aggresive exhaust under certain situations and a quiet one in others, ie, long istance cruising. The Dynomax VT has a valve inside that will open when you get on it, and closes down when it's in steady state cruising. Frankly, the Kizashi sounds like a sewing machine and the exhaust tone has no soul, in my opinion. Oh well, will leave well enough alone.

[murcod]

It is possible to get something like you desire. I had this system fitted to my last vehicle: http://www.rs192.co.uk/ ; obviously it's a totally different vehicle, but I didn't want anything loud at cruise speeds nor a "look at me" noise every time you slightly accelerated. I was very surprised with how quiet it was compared to the stock system at normal cruising speeds, but the sound was deeper. It gave decent power gains and sounded very nice at full throttle.

Looking at the system- they hadn't gone for a large increase in pipe diameter. The larger the diameter, the more noise you'll get. They also used straight through mufflers, but they were physically larger than the normal mufflers that such a system would use.

IMHO you might get what you're after by modifying your stock exhaust. The safest option would possibly be to first replace both rear mufflers with the largest straight through design you can fit in there. Keep the standard pipe size- it's exhaust gas velocity that helps make power, not the diameter of the pipe. Too large a diameter and you'll lose velocity and have a loud system. If you're not happy with that result (ie. still too quiet) then look at replacing the centre resonator.

PS: A friend had virtually the same vehicle as mine and went for a full custom system. He had endless trouble with interior droning and tried everything to limit cabin noise. (I think his biggest mistake was not sticking with 2.25" piping and going up to 2.5".)

[BxKizashiS]

the kizashi is way to quick, i def need to upgrade my exhaust