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GUESS THE DECIBELS? EDIT: NOT GOOD!
matt.c - 25/6/09 at 10:27 PM

Time for a little game as its nearing the end of the week. Im testing how loud my indy is at a static test.

Test will be taken @ 3/4 RPM which is 9k

My indy is powered by a ZX9R engine and has a standard R1 can and a pipercross sausage filter.

So then, how loud do you think it will be?



[Edited on 27/6/09 by matt.c]

BenB - 25/6/09 at 10:28 PM

101.1db?

twybrow - 25/6/09 at 10:33 PM

103db

Steve Hignett - 25/6/09 at 10:39 PM

I think it will be quieter when wasting time doing a stupid static test at 3/4 revs than if it was doing Max Revs being ragged down the road mate..............


nitram38 - 25/6/09 at 10:43 PM

103.7db

eccsmk - 25/6/09 at 10:43 PM

100db

can you do one at full chat some where??

there must be a nice private road near you somewhere

matt.c - 25/6/09 at 10:57 PM

Marham airfield = 105Db
Snetterton race track = 102Db

I think i might struggle with the snetterton Db's

eccsmk - 25/6/09 at 10:59 PM

quote:
Originally posted by matt.c
Marham airfield = 105Db
Snetterton race track = 102Db

I think i might struggle with the snetterton Db's


b*gger i best get my exhaust changed then
or i wont be allowed at marham

mark chandler - 26/6/09 at 12:12 AM

I suspect your noise is induction, a standard R1 can is quiet relatively.

Better to box them filters in, at the same time duct the air to the front of the car pointing away from the exhaust.

Sticking a 90 degree bend on the exhaust exit will also kill a little noise, it does not travel around bends well.

Steve G - 26/6/09 at 12:19 AM

99.1dB

flak monkey - 26/6/09 at 06:58 AM

I reckon it will under 100dB.

How do they do the noise tests at tracks? Is it a driveby monitoring?

Guinness - 26/6/09 at 08:17 AM

I've just lent my dB meter (an un-calibrated Maplin's one) and some parts to SteveB for his SVA re-test.

His R1 powered car with sausage filter and an R1 can was 103dB.

With my Pipercross Airbox, and an exhaust baffle, he passed the noise test with flying colours at 95dB.

I'd guess you would be around the 104dB marker at 3/4 max revs.

Mike

DM - 26/6/09 at 10:10 AM

quote:
Originally posted by flak monkey
I reckon it will under 100dB.

How do they do the noise tests at tracks? Is it a driveby monitoring?


both -

stationary test is usually something like 0.5 metres 45 degrees away from the exhaust at 3/4 max revs, which will have a higher threshold than the driveby test

eg, bedford autodrome

101 db static and 87db drive by

mistergrumpy - 26/6/09 at 02:01 PM

3/4 is 9000rpm? I think I only declared 9000rpm tops so only had to be tested at 7500rpm

eccsmk - 26/6/09 at 02:10 PM

by the way matt whats the prize for the nearest answer

matt.c - 27/6/09 at 10:07 AM

What do i rev it too as it says on the clocks its a 12 red line?

matt.c - 27/6/09 at 10:08 AM

quote:
Originally posted by eccsmk
by the way matt whats the prize for the nearest answer


LOL a photo of my car on a trackday.

eccsmk - 27/6/09 at 06:50 PM

quote:
Originally posted by matt.c
quote:
Originally posted by eccsmk
by the way matt whats the prize for the nearest answer


LOL a drive of my car on a trackday.


sounds good to me

flak monkey - 27/6/09 at 07:19 PM

And the results are in....

80dB ticking over

106dB at 9k rpm (3/4 max)

95dB at 6k rpm

Induction noise was negligable.

Results are with a std R1 can

David

matt.c - 27/6/09 at 07:31 PM

ARGH!!!! WTF do i do now!

eccsmk - 27/6/09 at 10:22 PM

more importantly when does Guinness get his piccy

u2u on its way matt.

RickRick - 29/6/09 at 12:02 PM

frig your rev counter!