DF500 Posted April 16, 2012 Share Posted April 16, 2012 Just bought an R500 with a track day silencer but with foam airbox cover and been warned it may fail the 98db drive by sound limit at Donnington - anyone know what the likely noise level is for this combination? Link to comment Share on other sites More sharing options...
Supersprint1988 Posted April 16, 2012 Share Posted April 16, 2012 May I suggest a light foot on the throttle here 😬 😬 Edited by - Supersprint1988 on 16 Apr 2012 21:10:42 Link to comment Share on other sites More sharing options...
Area Representative Nick Chan Posted April 17, 2012 Area Representative Share Posted April 17, 2012 Have you got a K series or Duratec R500? If its the K series with a short exhaust (with a cat or a cat bypass pipe) on and a foam Pipercross filter, its likely to be over 100 dbs. I recently bought my KR500 and it was between 104-108dbs even with a cat and newly packed silencer so I have fitted a Raceco 7.25" silencer and a carbon airbox to bring it down to a decent level. I reckon I will be okay now for a 98 db drive by. Nick Link to comment Share on other sites More sharing options...
bertie Posted April 17, 2012 Share Posted April 17, 2012 I have an R400 K series which runs the same roller throttles which are a big part of the noise issue and even with a Raceco silencer and an airbox I cant meet the 98dB drive by without some ....ahem....appropriate use of throttle at Donington. I'm just looking to get mine made rear exit so the thing isn't shouting out it's end straight at the pit wall! Link to comment Share on other sites More sharing options...
Pezky Posted April 17, 2012 Share Posted April 17, 2012 but of course if it a Duratec R500, the exhaust is on the wrong side Link to comment Share on other sites More sharing options...
DF500 Posted April 18, 2012 Author Share Posted April 18, 2012 It is a new R500 and so a Duratec. I can borrow a carbon fibre airbox cover but I am worried that even that might not be enough and I am bound to forget to ease the throttle at the right point.... Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted April 18, 2012 Member Share Posted April 18, 2012 Has anyone found a reliable app for testing sound levels at home? Jonathan Edited by - Jonathan Kay on 18 Apr 2012 10:19:29 Link to comment Share on other sites More sharing options...
Roger Ford Posted April 18, 2012 Share Posted April 18, 2012 Unless you're aiming to drive by your house at ~ 100mph, I can't really see how that would help. Link to comment Share on other sites More sharing options...
DF500 Posted April 18, 2012 Author Share Posted April 18, 2012 Q102 - just being a bit dim but do you mean that the silencer is on the "right" side, so I only have to worry about the airbox? Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted April 18, 2012 Member Share Posted April 18, 2012 I was thinking of testing before track days. All the ones I've been on use testing while stationary. I've just asked the same question here. Jonathan Link to comment Share on other sites More sharing options...
James.S Posted April 18, 2012 Share Posted April 18, 2012 It is the induction noise that is the problem. The carbon aribox (available from CC track day airbox istr) should sort it out, otherwise take it off and blank over the bonnet cutours with tank tape. The drive by meter at Donnington is at the start of the pitwall, so you can always lift as you go passed it. Works for me. Link to comment Share on other sites More sharing options...
Pezky Posted April 18, 2012 Share Posted April 18, 2012 with the K R500 the exhaust would be on the LHS, therefore giving it he beans might kick off the driveby meter. Hopefully with your exhaust being on the drivers side it should reduce the noise. Not sure how Donnington run but at Bedford they will blackflag Caterhams for being too loud - even if a 911 with race exhaust triggers it Link to comment Share on other sites More sharing options...
Area Representative Nick Chan Posted April 18, 2012 Area Representative Share Posted April 18, 2012 I have only ever been black flagged once and that was at Donington for noise. The blackbird was just 0.3db over the limit and even the Marshall was apologetic for pulling me in! He advised me to stay right on the pit lane straight and lift very slightly and it would be fine. The blackbird isn't a very loud car but with your exhaust pointing away and if staying right, hopefully you will be ok. Nick Link to comment Share on other sites More sharing options...
MikeMolloy Posted April 18, 2012 Share Posted April 18, 2012 Nick - could I ask what your Blackbird gets for static noise tests? (And at what rpm?) What silencer(s) do you have fitted? Cat or not? Thanks! Link to comment Share on other sites More sharing options...
dannylt Posted April 18, 2012 Share Posted April 18, 2012 The static test obviously doesn't make much induction noise, but throttle bodies can be seriously loud - on my Duratec much more so than the exhaust. At Donington you can get away with a lift, not sure about Donnington . Link to comment Share on other sites More sharing options...
MartinP Posted April 18, 2012 Share Posted April 18, 2012 Hi DF500, There are 2 carbon fibre airboxes available from CC for the D500. One which is effectively a cover that sits over the foam filter and has a slit around the top on the part that sticks through the bonnet IYSWIM and hence sucks in nice cold air. It will reduce noise a little but because the intake is in open air and not under the bonnet then depending which track you go to may not be enough. The other is what I seem to recall being called the quiet or trackday airbox. This is a closed carbon fibre airbox with what I can best describe as a spout sticking out one end with a conical air filter attached. This replaces the foam filter entirely and the conical filter is housed underneath the bonnet hence is much quieter. This is the ultimate solution available I believe. That's not the end of the story however as each has an impact on engine output, one positive, the other negative. I have one of each for my D500 and also have a new spare quiet airbox. Drop me a blatmail in case you want to look into this a bit further. Where are you based as you could always drop over and try for yourself? Link to comment Share on other sites More sharing options...
purpleone Posted April 18, 2012 Share Posted April 18, 2012 Hi I have an R500K 2002 and even though i had a large Raceco silencer fitted and a full caterham carbon airbox it was still making over 108db on static noise tests (pops and bangs).I then had the engine mapped at track n Road and it and now it has only 93-94db static and can be driven on full throttle anywhere around bedford autodrome without tripping any of the sound pic ups.its not just the big silencer and the airbox,if the car is popping and banging i think you will struggle anywhere. Link to comment Share on other sites More sharing options...
Area Representative Nick Chan Posted April 18, 2012 Area Representative Share Posted April 18, 2012 Quoting Fred Gassit: Nick - could I ask what your Blackbird gets for static noise tests? (And at what rpm?) What silencer(s) do you have fitted? Cat or not? Thanks! Hi Fred, I can't quite re-collect the noise out put for the static test but I think it was around 97 when I was last at Outlon and well within their limits. Revs-wise it will have been about 5.5-6k. As mentioned before, the 'Bird isn't a noisy car I reckon. It has got a 4-2-1 system with a 6" can and the usual side output. It originally was a rear exhaust system, but the previous owner though it was way, way too quiet (esp with its big carbon airbox 😬) and had the rear section removed and the side pipe attached. I run it with a TTS foam filter and their re-jet kit and it has made a massive difference both in power and induction noise it produces - both just right Nick Link to comment Share on other sites More sharing options...
bertie Posted April 18, 2012 Share Posted April 18, 2012 Quoting alicazsam: Hi I have an R500K 2002 and even though i had a large Raceco silencer fitted and a full caterham carbon airbox it was still making over 108db on static noise tests (pops and bangs).I then had the engine mapped at track n Road and it and now it has only 93-94db static and can be driven on full throttle anywhere around bedford autodrome without tripping any of the sound pic ups.its not just the big silencer and the airbox,if the car is popping and banging i think you will struggle anywhere. That's exactly my setup in my R400 and 1 was hitting 104. Is there anyone good who can remap the MBE ecu who is a bit closer to derby than track n road? Link to comment Share on other sites More sharing options...
MikeMolloy Posted April 19, 2012 Share Posted April 19, 2012 Nick - did you buy the 'bird form a guy named Mike in North Wales? If so I have the rear part of the exhaust system! Going to have to go "2-box" to solve the TD noise issue once and for all (I hope!). Usually a BEC gets tested at 3/4 max rpm - so 8000+ for the blackbird. Link to comment Share on other sites More sharing options...
Area Representative Nick Chan Posted April 19, 2012 Area Representative Share Posted April 19, 2012 Hi Fred, Yes I bought Mike G's car. So that's where that bit went...! 😬 I was surprised when Mike mentioned it was originally a rear exit system. Hopefully it will do the trick with your car. Have you got one of the original blackbirds? I have got a rear system waiting for my R500 as you can see noise limits getting tighter for our cars ☹️ Nick Link to comment Share on other sites More sharing options...
wild bill Posted April 20, 2012 Share Posted April 20, 2012 I use David Bannach's 'Decibels' as an i phone app and it's accurate as a home test, haven't tried drive bys for induction noise but static noise test has been accurate. It will at least give you an idea as to whether you are in with a chance of passing the static or not. Link to comment Share on other sites More sharing options...
MikeMolloy Posted April 20, 2012 Share Posted April 20, 2012 My car has been gathering dust, ignored and unloved, for a couple of years now. It is set up primarily for track use (slicks, etc.) and I couldn't meet the noise limits for the events I wanted to go to (usually 98dBA static)! In the meantime I have re-built the exhause headers with copious amounts of high-temp silicone to try and stop the popping & banging, plus bought a ludicrously expensive R500 silencer to mate up with the transverse rear box. Silvestone quiet evenings here I come! Link to comment Share on other sites More sharing options...
Area Representative Nick Chan Posted April 24, 2012 Area Representative Share Posted April 24, 2012 Hi Fred, just to give you an update from yesterday's trip to Cadwell. The blackbird came in at 98 dbs at 5,700 which was the given to me by the marshall. There were 3 other blackbirds too and no problem with noise limits I think Cheers Nick Link to comment Share on other sites More sharing options...
MikeMolloy Posted April 24, 2012 Share Posted April 24, 2012 5700? What happened to being tested at 3/4 max? 98 at 5700 is going to be a lot more at 8K5 I should think! From the MSV Cadwell notes: "All vehicles participating in track days at Cadwell Park must conform to the noise limit, on a static test, of 105 dB(A). Noise checks to establish adherence to the relevant limit will be conducted in accordance with current measuring methods as defined by the MSA. Essentially this means that the noise test shall be measured from a position 0.5m behind the exhaust at a 45 degree angle, with the engine running at ¾ maximum revs." Link to comment Share on other sites More sharing options...
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