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Radical Noise Limits
spdpug98 - 16/7/09 at 02:20 PM

In between some site meetings today, I popped into Castle Combe to watch a bit of testing for this weekends Dunlop Great and British Championship and some of the Radicals where out on track

This something I have been thinking about for a while now, why are the Radicals so quiet. We all seem to struggle to get our cars quiet enough for SVA / IVA / Trackdays etc, so why can Radical do it. At the moment, I think that if I drove my car into to Combe they would tell me not to bother even before they got the dB meter out

Guinness - 16/7/09 at 03:42 PM

At a guess, they have a carbon airbox which is enclosed underneath a fibreglass body.

Then a big silencer, again enclosed underneath a fibreglass body.

Mike

spdpug98 - 16/7/09 at 03:49 PM

quote:
Originally posted by Guinness
At a guess, they have a carbon airbox which is enclosed underneath a fibreglass body.

Then a big silencer, again enclosed underneath a fibreglass body.

Mike


I guess it will be the airbox then, as my engine is also enclosed under a fibreglass body.

As I guess even if you encased my exhaust in a fibreglass body it wouldn't make that much difference to the noise that exits the outlet

Looks like I will have to make an airbox to reduce the induction noise, the accoustic foam I have in the in the engine bay reduced it enough for SVA, and probably enough for a circuit static test but I am sure it would fail on drive-by noise

iiyama - 16/7/09 at 03:55 PM

bunkin off again??

spdpug98 - 16/7/09 at 04:00 PM

quote:
Originally posted by iiyama
bunkin off again??


Who me........Never!!!

I was on my way back from an overnight in Swansea to a meeting in Swindon so in theory it was on the way!

ETA: Ian I just thought...someone mentioned Carbon!!! That could be your next project...feel free to try it out on my car

[Edited on 16/7/09 by spdpug98]

iiyama - 16/7/09 at 04:04 PM

carbon airbox for an R1 anyone??

spdpug98 - 16/7/09 at 05:14 PM

quote:
Originally posted by iiyama
carbon airbox for an R1 anyone??


Sounds like a plan when (if) I get some funds together!! I have a standard one already which may or may not fit

iiyama - 16/7/09 at 05:29 PM

Well if it does maybe a mould can be taken from that...?? Makes things a bit cheaper!

procomp - 17/7/09 at 07:10 AM

Hi

There silencers also have Cats inside them to comply with MSA regulations. Cats can reduce noise by a good margin. Also power if not designed correctly.

Cheers Matt

gixermark - 17/7/09 at 10:44 AM

don't think there are any with cats Matt ? Radicals are classed as 'racing cars' therefore do not need cats..

at donington a couple of wk ends back the usual 98db drive by limit was in force, and loads of radicals failed not surprisingly.. some passed with their 'quiet cans' others like me had a DB eater that always seems to work - did with my blade striker too..

iiyama - 17/7/09 at 10:50 AM

All race cars require cats now, thought it was an MSA ruling?

gixermark - 17/7/09 at 01:58 PM

its the terminology of 'race' cars vs more production or 'kit' cars i believe.... I ain't a blue book expert but its in their somewhere..............