Db level comparison for those considering track action
Discussion
Thought it may be of interest to some who may be considering track days (highly recommend)
Just swapped my exhaust back to a standard system after a summer of crackling overrun and howling courtesy of an Austec modded system (cheers Sean)
It can be fitted with very tidy and easy to fit Tower View racing tail pipe inserts which have the following effect, as tested today with calibrated meter.
Revs - Open pipes / With inserts - DB reduction
3000 - 99 / 95 -4
3500 - 102 / 97 -5
4000 - 105 / 98 -7
4500 - 107 / 101 -6
at 500mm and 45 degrees
Puts it just within the limits at 4000 revs for 105 Db and 98Db limit track days
The figures look contorted but I can assure you these are true figures
Let's just hope they use the same calibrated meters at my next day at Goodwood on the 9th Dec. It's a 98 Db day. (and that they don't ask me to rev it past 4K
)
Time to bed in the R888's
Moose
Just swapped my exhaust back to a standard system after a summer of crackling overrun and howling courtesy of an Austec modded system (cheers Sean)
It can be fitted with very tidy and easy to fit Tower View racing tail pipe inserts which have the following effect, as tested today with calibrated meter.
Revs - Open pipes / With inserts - DB reduction
3000 - 99 / 95 -4
3500 - 102 / 97 -5
4000 - 105 / 98 -7
4500 - 107 / 101 -6
at 500mm and 45 degrees
Puts it just within the limits at 4000 revs for 105 Db and 98Db limit track days
The figures look contorted but I can assure you these are true figures
Let's just hope they use the same calibrated meters at my next day at Goodwood on the 9th Dec. It's a 98 Db day. (and that they don't ask me to rev it past 4K
) Time to bed in the R888's
Moose
Edited by The Moosehunter on Thursday 9th November 19:29
Edited by The Moosehunter on Thursday 9th November 19:30
Edited by The Moosehunter on Thursday 9th November 19:30
Interesting figures. Do you notice any difference in performance? My 98 500 usually measures bang on 100 at around 3600. ( that is at 0.5 m ) I think box was sleeved by the previous owner but I still have pre cats fitted.
-7db is an enormous reduction, that is half, half again and a bit more.
-7db is an enormous reduction, that is half, half again and a bit more.
steve-v8s said:
Do you notice any difference in performance?
Only tried them out today for the first time static
May have to wait until the next 105 Db day to test them properly, with / without inserts
Was the 3600 a tested level for a reason
My understanding is that it's 2/3 rd's of max revs. Anyone confirm ?
The Moosehunter said:
steve-v8s said:
Do you notice any difference in performance?
Only tried them out today for the first time static
May have to wait until the next 105 Db day to test them properly, with / without inserts
Was the 3600 a tested level for a reason
My understanding is that it's 2/3 rd's of max revs. Anyone confirm ?
thats right andy
3/4 at 500mm/45 degrees
andy
tvrmonster
It seems to me the biggest factor is the weather conditions on the day. I was measured at 105dB at Goodwood on a cold damp day. Similar reading at an airfield day, similar weather conditions. Hot, summer day at same venue and reading is 96dB. "Normal" reading is about 99dB. Standard Griff 500.
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