Oversteer Posted March 17, 2016 Share Posted March 17, 2016 (edited) I love the sound my car makes and static it's well within most track day limits, however on my first lap at Bedford I received a 'NOISE' board, meaning I was very close to the drive by limit of 87.5 dB. I had to then essentially 'drive around' the microphones; I still had an amazing day but would prefer to be able to focus on my driving rather than being worried about being black flagged for noise (more than ten cars were black flagged on Monday, apparently the wind exacerbated their already strict limits, some cars were on their first lap, gutted for them). Mine has: Cobra Resonated Catback; Motordyne Y pipe; Berks HFC (and HKS drop in air filters - 350 HR). My options seem to be: 1. Put the stock cats back on and have remapped (was remapped after fitting the Berks, releasing 9bhp, so guess will need redoing? As Uprev has been paid for, should just be the cost of remap labour) 2. Add exhaust valve to reduce noise, only one I've found is this, would need to find a place to fit it and no guarantee of effectiveness etc: http://www.ebay.co.u...=STRK:MEBIDX:IT 3. Bung / muffler etc options, another Z at Bedford had a pair of these, I believe they just slot in the exhaust tips (? clamped on somehow to keep them there?) - can obviously be removed, requires less outlay in terms of purchase and labour and I'll retain those extra 9bhp and raspy bark for when I'm not worried about noise microphones! http://www.ebay.co.u...=STRK:MEBIDX:IT 4. Go to an exhaust specialist and have a silenced pipe made and fitted, not sure where I'd go for this and what section of exhaust would be replaced and other negative effects such as power loss / need for remap etc. Not sure any of these would be sufficient to ensure meeting the drive by limits; has anyone been in a similar situation and could offer any advice / not been in this situation but have more experience than me etc! If anyone can point me in the right direction for any of the above options (or other options that I've not mentioned / thought about, such as the Y pipe etc), that would be most welcome! Edited March 17, 2016 by Oversteer Quote Link to comment Share on other sites More sharing options...
Jetpilot Posted March 17, 2016 Share Posted March 17, 2016 (edited) I wouldnt have suggested that was a loud set up, I know the Cobra back box isnt that big though, same goes for the resonated centre pipe. Personally if it was me i would do another day before making a decision, it may well be just the wind carrying the sound in the wrong direction as mentioned. If it happens again and your close the limit (remembering db works on a weird scale, 3db more could mean its twice as loud) bungs are the easy and quick option for a remedy, if it continues to happen and you keep getting black flagged i would just change the system it will be more cost effective rather than trying to modify and add in silencers. Edited March 17, 2016 by Jetpilot 1 Quote Link to comment Share on other sites More sharing options...
Ekona Posted March 17, 2016 Share Posted March 17, 2016 Just buy a stock exhaust (if you don't still have yours) then swap it over before any trackday. 10 min job, even on a driveway, as long as you keep the bolts well lubed. Cheapest and easiest way by far. 2 Quote Link to comment Share on other sites More sharing options...
Jetpilot Posted March 17, 2016 Share Posted March 17, 2016 (edited) What was your static reading and drive by out of interest? I managed to get on at Thruxton, the strictest in the country, 92 db static with drive bys with hfc's and dual exhaust. I cant believe any Zed should fail unless especially with hfcs unless running a single or k1/buddy club etc. Edited March 17, 2016 by Jetpilot Quote Link to comment Share on other sites More sharing options...
Oversteer Posted March 17, 2016 Author Share Posted March 17, 2016 (edited) Static it was 95 then settled quickly to 93. May be it was the just the wind. Will see how I get on at Brands - hopefully it won't be a windy day! Anyone know where to get the correct bungs? Edited March 17, 2016 by Oversteer Quote Link to comment Share on other sites More sharing options...
Jetpilot Posted March 17, 2016 Share Posted March 17, 2016 Thats good for a static db mate, i would just say the wind was blowing in the wrong direction especially if loads of others were getting pulled for it. Bungs can easily be found on ebay. Quote Link to comment Share on other sites More sharing options...
Oversteer Posted March 18, 2016 Author Share Posted March 18, 2016 Thats good for a static db mate, i would just say the wind was blowing in the wrong direction especially if loads of others were getting pulled for it. Hope so mate! Just realised you're from Poole too! Quote Link to comment Share on other sites More sharing options...
Jetpilot Posted April 30, 2016 Share Posted April 30, 2016 Just for reference I did Bedford today and got a couple of noise boards, I was one db under the limit from getting black flagged. So would suggest its pretty stringent, never had any issues before. Quote Link to comment Share on other sites More sharing options...
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