Track Day silencing %2d HELP!
Discussion
I bought a Club Sport 1100 at the end of November last with a view to using it for track days. Problem is that my nearest tracks are Castle Coombe and Goodwood. Both are very stricked on noise levels so has anyone out there actualy cracked this one. When I spoke with Radical even they were unsure if their 'quiet' silencer would meet the Goodwood limits so I need some help on this one as I dont want to spend a lot of money on something that wont do the job. Next question is about lights. My CS has rear stop & tail and a fog light. Will I be turned away for not having indicators or headlights?
>> Edited by Radical Chris on Sunday 5th February 10:50
>> Edited by Radical Chris on Sunday 5th February 10:50
Chris, have you run the car at these tracks yet? The radical "quiet silencer" is supposed to run at 98db not sure if thats quiet enough for coombe and goodwood though. As for indicators and headlights, they are not a requirement for trackdays although brake lights are. Merlin motorsport at coombe have a range of add on silencers for people who struggle with noise on their cars. hope this helps, good luck.
Tony.
Tony.
My Clubsport wouldn't get anywhere near the 100dB limit at Combe, but that had the standard exhaust on. The Radical trackday one is a lot better, iirc at Brands my car was 107dB drive by and another CS with the trackday can on it was 102db drive buy. Have a look in the old posts on this forum as there is some information regarding silencing.
I have tried at cc with the 98db quiet exhaust and failed miserably (and I'm still grumpy about it!). Basically there's nothing 98db about that exhaust! The only way you can get round it with that exhaust is to be economical with the revs. With the normal CS dash, they test at Combe with 3 yellows showing at rack days. Radical reckon that you can just about do it with one yellow just glowing. So you have to convince whoever is testing that one yellow is 3/4 max revs (or 2/3 if that's what's being tested at - can't remember which at cc).
The problem is that even with a quiet exhaust, the induction and other engine noise is just loud!
I have seen a CS at Goodwood and some here have been. You just need to be convincing about the rev lights. Not sure I can take the rejection though if it goes wrong!
I have resigned myself to only going to noisy days or tracks that it can cope with. Donny on a normal day seems of with the quiet exhaust. You will prob need to take itr easy past the drive-by mic though. Brands should also be ok. Rockingham ditto.
I've got a Caterham for doing other track days whether it's where it needs to be quieter or at airfields where the Rads are not allowed as well as being too loud! I suspect that the rad will move on and the caterham will stay!
Graham
The problem is that even with a quiet exhaust, the induction and other engine noise is just loud!
I have seen a CS at Goodwood and some here have been. You just need to be convincing about the rev lights. Not sure I can take the rejection though if it goes wrong!
I have resigned myself to only going to noisy days or tracks that it can cope with. Donny on a normal day seems of with the quiet exhaust. You will prob need to take itr easy past the drive-by mic though. Brands should also be ok. Rockingham ditto.
I've got a Caterham for doing other track days whether it's where it needs to be quieter or at airfields where the Rads are not allowed as well as being too loud! I suspect that the rad will move on and the caterham will stay!
Graham
My experience at two circuits, Goodwood and Donington is that you have to be very econonomical 
with the truth for the static test. If you can get through that on track short shift and even back off where the noise sensors are. Our 1100 clubsport has a re-packable track day silencer, we also have an extra baffle up the exit pipe which we bought from the guys at Donington circuit. They sell them to bikers. We fitted it at a Donington track day and were ok on track for the rest of the day. We have also used the car at Goodwood but were warned 
and had keep the revs down.
>> Edited by VSP90 on Monday 6th February 11:35
with the truth for the static test. If you can get through that on track short shift and even back off where the noise sensors are. Our 1100 clubsport has a re-packable track day silencer, we also have an extra baffle up the exit pipe which we bought from the guys at Donington circuit. They sell them to bikers. We fitted it at a Donington track day and were ok on track for the rest of the day. We have also used the car at Goodwood but were warned and had keep the revs down. >> Edited by VSP90 on Monday 6th February 11:35
Thanks guy's - seems like the topic bounced off the walls a bit! Firstly I looked back at all the messages but found very little hence my call for help. I have on rare occasions seen Radicals running at Goodwood. Just before Xmas there was an S3 I think with an additional muffler added to the rear of the standard box, I guess they managed to convince the marshals they would keep it short shifted or whatever. I guess the thing to do is add a normal tacho and turn the limiter down to about 9000 rpm or so at these places. Last point is for all you Silencer Manufacturers out there - Bike Engine cars are 'in'! You have the boxes in your standard range so all you have to do is establish what combinations are required to keep the noise down. After that your average DIY person should be able to assemble a system for their particular installation. Last point - not much use buying the Radical 'quiet box' then unless you want to waist money!
Chris, I my view it's not just the exhaust noise that is the problem with our cars. The induction noise and overall howl that you here on drive by is music to my ears but difficult if not impossible to control on a fibre glass bodied car. They may be a little bit more expensive but there are plenty of track days you can do with a Radical. Last year we did Brands (GP and Indy) Silverstone,Oulton Park,Snetterton with no noise issues and as mentioned in my previous post Donington too. The other thing to consider also is that the tracks that restrict you to 98db tend to run in sessions three or even four an hour with a limited number of cars on track which gives much less track time for your money.
>> Edited by VSP90 on Monday 6th February 15:24
>> Edited by VSP90 on Monday 6th February 15:24
Hi,
I ran my SR4 at Goodwood last year on the quiet silencer from radical. Did the usual trick of low revs on the static test to pass. But on track there were no problems with the drive bys around the circuit. The marshalls kindly pointed them out to me so I could lift off a little. But by the afternoon we where at full chat with no problems. I think if your nice and show you care about the noise they'll do their best to keep you running.
Simon.
I ran my SR4 at Goodwood last year on the quiet silencer from radical. Did the usual trick of low revs on the static test to pass. But on track there were no problems with the drive bys around the circuit. The marshalls kindly pointed them out to me so I could lift off a little. But by the afternoon we where at full chat with no problems. I think if your nice and show you care about the noise they'll do their best to keep you running.
Simon.
Thanks guys for the continued support on this. I better start with saying that due to domestic circumstances I am somewhat limited on the circuits I can get to, Goodwood is the closest followed by Coombe, Brands and Silverstone. I really have problems getting to some of these for drivers briefing let alone some of the others - I would love to do Donington but maybe sometime. Sorry guys, it's my problem so that leaves me with the furthest two for 105db.
Yes I agree the problem is not limited to the exhaust but some of you are managing to blagg your way onto the circuit.
Prawn, how I envy you.
Simon, do you know what db they measured on your SR4 and at what revs?
VSP90 - your additional baffle, do you know if there is a similar item in the Demo Tweaks catalogue (assuming you have one)? I have done some 30 min. session T/D's, always found that the tyres tend to go off a bit and start to spoil the fun.
Regarding the standard box, I picked up somewhere that the effectiveness depends on how tight the repacking is. Anyone got any ideas?
RobC, have you got hold of that wiring diagram yet?
Regards,
Chris
Yes I agree the problem is not limited to the exhaust but some of you are managing to blagg your way onto the circuit.
Prawn, how I envy you.
Simon, do you know what db they measured on your SR4 and at what revs?
VSP90 - your additional baffle, do you know if there is a similar item in the Demo Tweaks catalogue (assuming you have one)? I have done some 30 min. session T/D's, always found that the tyres tend to go off a bit and start to spoil the fun.
Regarding the standard box, I picked up somewhere that the effectiveness depends on how tight the repacking is. Anyone got any ideas?
RobC, have you got hold of that wiring diagram yet?
Regards,
Chris
Hi Chris, I suggest you speak to or go and see Mithrel (not sure of the spelling) Racing they are based at Goodwood circuit. They will hire you a supertrap type gismo (or even a Ferrari!!) which may well do the trick. My previous TD car was a Vauxhall engined Westfield. We were chucked off with it (drive by) at Goodwood a couple of years ago they suggested we go and see Mithrel and their bolt on thing got us back on track. They were very helpfull and produced a box full of add on's many of which they had made themselves. I would take your car to them and I am sure they will be able to help.
The baffel we have up our exhaust exit pipe is similar to the decibel insert shown on page 275 of the 2006 DT Catalogue. The one we have is made for bike silencers. Give Donington circiut a ring, when we bought ours they had a box full in differant sizes and shapes so I don't think it is a one off. Good Luck.
The baffel we have up our exhaust exit pipe is similar to the decibel insert shown on page 275 of the 2006 DT Catalogue. The one we have is made for bike silencers. Give Donington circiut a ring, when we bought ours they had a box full in differant sizes and shapes so I don't think it is a one off. Good Luck.
Chris,
I think from Memory it was 98db day and the car just slipped in under 98db on the quiet silencer. I kept the revs initially below the green lights but was asked to be a bit more generous as I think they new what I might be up to. I pushed it to one green light and it still passed. The marshall didn't show me the reading for the Radical, but with my 996 C4S the left bank registered 101db and the right 96db they said I failed the static but still let me out, go figure.
I've found when the marshall is testing, that if you very slowly increase the revs their perception of how far up the range you've gone is marred and makes it feel like your higher up the range than you really are. If you blip it up too quickly and over rev in there presence they get a reference of the rev range and generally ask for more revs than you'd like to give. Hope that makes sense.
I think from Memory it was 98db day and the car just slipped in under 98db on the quiet silencer. I kept the revs initially below the green lights but was asked to be a bit more generous as I think they new what I might be up to. I pushed it to one green light and it still passed. The marshall didn't show me the reading for the Radical, but with my 996 C4S the left bank registered 101db and the right 96db they said I failed the static but still let me out, go figure.
I've found when the marshall is testing, that if you very slowly increase the revs their perception of how far up the range you've gone is marred and makes it feel like your higher up the range than you really are. If you blip it up too quickly and over rev in there presence they get a reference of the rev range and generally ask for more revs than you'd like to give. Hope that makes sense.
Simon, that's a very impressive 98db. Do you know what revs that actually relates to? If it's the same as the clubsport, that's after 3 yellows. In my CS with a brand new radical quiet box (the SR4 one apparently) plus a big dongle on the back, I get about 102 with 3 yellows. It's under 100 with 1 yellow lit, I have no idea how I could get it to 98! I'm just going to stick to noisy days, I got turned away twice last year and apart from the waste of time and money, it gets me really annoyed!
Thanks again. Decided I am going to make up a system out of two new boxes - first one replacing the original and exiting in a right angle bend. The second one (about 50cm) will run longitudinally to the right hand side of the car. Now I figure if this brings the sound within 98db I will be cuffed. Reason for pointing the end pipe into the circuit is to minimise the sound being picked up by the recorders on the outside of the circuit, (Goodwood). Having said that it still may cause a problem with the drive-by unless I can convince them to stand on the outside of the circuit.
Hey, its got to be done between now and April so I will let you know how I get on.
Anymore advise
?
Hey, its got to be done between now and April so I will let you know how I get on.
Anymore advise
?
.gridgway said:
Simon, that's a very impressive 98db. Do you know what revs that actually relates to? If it's the same as the clubsport, that's after 3 yellows. In my CS with a brand new radical quiet box (the SR4 one apparently) plus a big dongle on the back, I get about 102 with 3 yellows. It's under 100 with 1 yellow lit, I have no idea how I could get it to 98! I'm just going to stick to noisy days, I got turned away twice last year and apart from the waste of time and money, it gets me really annoyed!
Not sure what rev range this relates to, but its 10500 on the shift lights so if the increments are accurate it must be around 2.5-3k in revs. Sounds like your stuggling. Have you run the quiet exhaust for some time as the wadding may have degradded and in need of repacking. Not sure how you do this on the quiet exhaust as its welded shut on mine.
On my race can though the changes in db from new to used is great, and it needs repacking regularly to keep the db's down. Also I have heard their can be variations in the quiet exhausts from new, some being much more effective than others. It may be that mine is particulary good. I've also spoke to Van at Slipstream and they used an SR4 quiet exhaust on the clubsport as the SR4 quiet exhuast is much better than the Clubsport quiet exhaust, which does apparently tend to fail low db static tests. Also check theat the marshalls are the standard 1meter from the exhaust as they often forget this and stick the mic right up against the tail pipe which is not the correct procedure apparently.
Hope this helps.
Simon.
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