Deacon 1357 Report post Posted March 26, 2014 Posted this on the other forum and forgot I hadn't put it here too (really need a post to both button...) Thought it may be of use in light of the other cobra thread. I got hold of a db meter to have a go at measuring how loud the cobra non res is after we used a fairly basic meter to measure a few at the last midlands meet. I positioned the meter on a tripod equidistant between the two tailpipes and level with them. These were the approximate readings I got:- Cold start up peak - 111db This fairly quickly settled to 99db Then settled again to 89db Eventually sat at 77db I'll get some static readings at 6k rpm when I can (couldn't do this to my neighbours on the drive way!) I'll also try and get some drive by figures (anyone know what sort of revs the car would generally be at when passing trackside meters?) Also arranging to meet up with Pitman and get some readings of his new set up and hopefully a few others. Will update this thread with new data as and when I get it. Share this post Link to post Share on other sites
Deacon 1357 Report post Posted March 26, 2014 Will has kindly offered to help with drive-by recordings and twigman said the V5 reading is at 3750rpm so will try and get readings at that and 6krpm too. Share this post Link to post Share on other sites
Mark@Abbey M/S 235 Report post Posted March 26, 2014 Noise tests for track days are recorded with the following procedure 1 metre away from the tailpipe at 45degress from the tailpipe. Car at 3/4 maximum revs. This is why your see track/race cars with extra red lines on rev counters and we also had a noise test Map asked for, swinging the cams around helps lower the noise level. Also any buildings or cars around the rear of the car will cause the db reading to differ. Also humidity and pressure (weather) makes a difference. I feel all the noise tests should be carried out with the same specs. Also your noise meter can you record the noise level in slow and fast levels this makes a difference as well. Share this post Link to post Share on other sites
Mark@Abbey M/S 235 Report post Posted March 26, 2014 Drive by noise levels differ at different tracks. Share this post Link to post Share on other sites
Deacon 1357 Report post Posted March 26, 2014 Slow and fast levels Mark? Share this post Link to post Share on other sites
rob275 1817 Report post Posted March 26, 2014 I'm assuming by that he means a reading over say 3-5 seconds taking a Median reading? Also thanks for the readings Share this post Link to post Share on other sites
Mark@Abbey M/S 235 Report post Posted March 26, 2014 Deacon, what's the make and model of the noise meter? Share this post Link to post Share on other sites
Deacon 1357 Report post Posted March 26, 2014 Not sure Mark - will try and dig the packaging out. It's nothing fancy though just a small handheld meter. I checked the calibration at work and it ties up with the calibrated equipment in our physics department. I wasn't claiming it to give perfect readings though. I was more thinking that some readings taken of different systems could give potential buyers a little more info. Share this post Link to post Share on other sites
toyokid 27 Report post Posted May 13, 2014 Hi Curious as to how much of the exhaust has been changed? Do you still have the 2nd cat? 111db would upset my neighbours! Stephen Share this post Link to post Share on other sites
Deacon 1357 Report post Posted May 13, 2014 Yeah it's just literally the cat back so second cat still in place. It is a tad loud at start up! Share this post Link to post Share on other sites
toyokid 27 Report post Posted May 13, 2014 Why not Ecutek your car and have less retard on the ignition for startup? Stephen Share this post Link to post Share on other sites
Keethos 842 Report post Posted May 13, 2014 Stephen, mine was de-catted non res and it was even louder, I was setting off car alarms in the vicinity, I dread to think how loud cold starts were but once warmed, at around 5500rpm, I was getting around 108db, now that I've got a resonated pipe (while still de-catted), when warm I'm getting around 89db. Share this post Link to post Share on other sites
Amazing Crow 10 Report post Posted May 14, 2014 My mate measured mine the other week, 103db at 5750rpm, non-res, 2nd cat delete. Exhaust has 6k+ miles on it. 45 degrees at 1m, mildly warm day in a wide valley, FYI. My Fensport remap lowered the start-up noise considerably. But I'm still not happy with the overall noise level and even though I don't want to pay any company even more money to fix a problem that is their own fault in the first place, I'll probably end up buying a resonator section at some point. I wish I had the spare cash to just get a more reputable system and show them the middle finger. Share this post Link to post Share on other sites
toyokid 27 Report post Posted May 14, 2014 just picked up a HKS system, this will be fitted next month when I have an Ecutek to reduce start up retard, rest of the system is 2.5" over pipe and 2.5" resonated 2nd cat replacement. I will provide feedback. Stephen Share this post Link to post Share on other sites
Deacon 1357 Report post Posted May 14, 2014 I had the original version of the ecutek map that was supposed to make it quiter at start up bit it did nothing. I'm waiting on getting a cable so that I can give the new version a try. Share this post Link to post Share on other sites
toyokid 27 Report post Posted May 14, 2014 I had the original version of the ecutek map that was supposed to make it quiter at start up bit it did nothing. I'm waiting on getting a cable so that I can give the new version a try. Not really sure what you mean by this? My understanding is that our cars retard the ignition on cold start? This gives rise to increased noise, even on a standard exhausted car? Recent Ecutek software iterations reduce this retard? If this is the case, then less retard from cold will reduce noise, whichever exhaust? Stephen Share this post Link to post Share on other sites
toyokid 27 Report post Posted May 14, 2014 At the other side of the ECUtek equation is power and torque, with a free flowing exhaust and 2nd de-cat, what figures might one expect to see? Thanks in advance. Stephen Share this post Link to post Share on other sites
Keethos 842 Report post Posted May 14, 2014 While already having a drop in air filter (where we witnessed roughly 6bhp increase), I had the dyno'd at Tuning Development and I got 192bhp I think, after the exhaust (non rest with cat delete) and an ecu remap by Adrian @ Fensport, I visited Tuning Development again and did another run where I got 204bhp (I think) so roughly another 12bhp, no idea what I was running when completely stock so no idea technically my increase with the 3 major mods on. Share this post Link to post Share on other sites
Kodename47 446 Report post Posted May 14, 2014 Recent Ecutek software iterations reduce this retard? If this is the case, then less retard from cold will reduce noise, whichever exhaust? Well, if the tuner adjusts the correct maps There's about 6 or 7 that need to be adjusted to get it to work properly. The reputable tuners on here should know what to change. Share this post Link to post Share on other sites
Deacon 1357 Report post Posted May 14, 2014 Not really sure what you mean by this? My understanding is that our cars retard the ignition on cold start? This gives rise to increased noise, even on a standard exhausted car? Recent Ecutek software iterations reduce this retard? If this is the case, then less retard from cold will reduce noise, whichever exhaust? Stephen When I had the car mapped by Abbey the cold start noise reduction was done but it didn't make any difference. However, there is a newer version of the map l which is supposed to help but I haven't been able to get the update yet as I need to arrange the cable. Share this post Link to post Share on other sites
toyokid 27 Report post Posted May 15, 2014 When I had the car mapped by Abbey the cold start noise reduction was done but it didn't make any difference. However, there is a newer version of the map l which is supposed to help but I haven't been able to get the update yet as I need to arrange the cable. I have booked an ECUtek session at Fensport the 1st week of next month, for retard attention and hopefully some more ponies, will fit my HKS exhaust a few days before so that I have less chance of upsetting my neighbours! Stephen Share this post Link to post Share on other sites
toyokid 27 Report post Posted July 18, 2014 Having done a cold start retard via Fensport My car is easy to live with and the HKS gives exactly what I was looking for, sporty sound when giving her some beans, then quiet at other times Sent from my iPad using Tapatalk Share this post Link to post Share on other sites
Keethos 842 Report post Posted July 18, 2014 I need to get myself to Adrian again to get the new maps put on my car, even had it booked in to get it done along with putting on the Springs that Dave gave me.....that was before I bloody dinked it though, then I cancelled my appointment as I need to get the car fixed before I continue with any major mods. But at the moment, I'm setting off as soon as I start the engine to try and keep the volume down as there are old people and new borns in the area Share this post Link to post Share on other sites
Special K 442 Report post Posted July 18, 2014 This weekend will be my first 'noise test' at Blyton with the new AVO 3" system... I have to say I am quite taken with the sound, even though it has the 'big box' rear rather than the separate silencers I had on the H&S. There is definitely a scoobie 'burble' there at low revs.. then, when I really give it some beans it's awesome... local guinea pigs spontaneously abort and old ladies imitate Lynford Christie.... Spec K 1 CHOSENMAN007 reacted to this Share this post Link to post Share on other sites
pepe 0 Report post Posted August 28, 2014 Hello there! someone has data only resonated cobra catback system? Share this post Link to post Share on other sites
