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xflow exhaust noise issue
CraigJ - 6/9/16 at 02:09 PM

Has anyone put a xflow through IVA? what size silencer did you use please?

I did a noise test on my striker and its around 120db and that's with a db killer in the end lol.

So i really need to fit a larger silencer but no idea how big to go. There is a 7 inch round one on carbuildersolutions for £210. Anyone think this will do the job?

phil m - 6/9/16 at 02:29 PM

Wow that's noisy. Mine went through the old Sva easily, way below the old limit.
The can was a basic Robin Hood one as in the picture.
What can do you have and are you picking up engine noise, not just exhaust

[img]http://[/img]

mcerd1 - 6/9/16 at 02:53 PM

first thing to ask is how and were did you measure it and with what kind of silencer ?

the next question is how sure are you that most of the noise is coming from the exhaust ?

CraigJ - 6/9/16 at 03:09 PM

measurement was taken 500mm from the exhaust at a 45 degree angle and 200mm from the floor. Revs at around 3800rpm.

It was around 93/94 db on tickover.

Its a 1700 xflow on twin 40's but no filters on at the time.

spiderman - 6/9/16 at 09:09 PM

quote:
Originally posted by CraigJ
twin 40's but no filters on at the time.


There you go, induction noise can add massively to overall noise. Pop some filters on and notice the difference, probably not enough to get below your target as twin 40's have 4 inlets sucking up the air as opposed to the single inlet of the original carb. If you can box them in for the noise test that may help.

mcerd1 - 7/9/16 at 06:25 AM

quote:
Originally posted by CraigJ
measurement was taken 500mm from the exhaust at a 45 degree angle and 200mm from the floor. Revs at around 3800rpm.

It was around 93/94 db on tickover.

Its a 1700 xflow on twin 40's but no filters on at the time.

As above no filters will make a massive difference

But it's hard to guess at how much difference any silencer will make without knowing what your current exhaust setup is...

Also did you measure that near to any walls or other reflective surfaces?

907 - 7/9/16 at 10:10 AM

quote:
Originally posted by CraigJ
measurement was taken 500mm from the exhaust at a 45 degree angle and 200mm from the floor. Revs at around 3800rpm.

It was around 93/94 db on tickover.

Its a 1700 xflow on twin 40's but no filters on at the time.






As a guide this is my car.

The Suttol 7
The Suttol 7



The exhaust is 4 into 1 then exits the side panel as 2" pipe and the can is 600mm long body x 150 diameter.
It's a 2" Ti perf tube inside and packed with Acosta-fil. ( *** Length is more important than diameter. *** )
The 907 Lotus engine runs Dellorto 45's with trumpets into an air box and a 3" flexi down to a K & N cone in the nose.
The engine revs to 7000 and produces 180 BHP @ 5600. The sound reading is 96 dBa.


Hope this helps.

Paul G