Crossflow noise for trackday

[Racer26]

Hi. Got a 1630 Roger King crossflow 1992 Sprint on twin Webers and a stainless 4 into 1 exhaust. I am preparing the car tor my first track day (Donington northwards), which is not booked yet. I am concerned the car may fail the noise test.
Any thoughts.

[Dave J]

so many variables - silencer, induction etc.
Only true way is to get it tested prior to booking. Do you live near a race circuit or buy a noise meter.

[Aeroscreens]

As a comparison my 1800 Roger King x/flow with 4:1 primaries and 6” Techcraft silencer (regularly repacked) was always around 98db, but with the original Caterham silencer some 10 years old and practically empty was way up at 114db.

As Dave says best to pop to your local circuit when there’s an event on and they’ll just do a noise test for you

[Ziplobb]

I remember going to an airfield trackway the first one ever in my x flo - I had no appreciation of sound levels and my car was over 102 db and so i could not take part - i think most 7 xflos will need attention and it wise to get it measured at a track before you book anything - I picked up a sound meter from a friend which has given nigh on the same reading as the chap at Goodwood when we have gone there so I can check my latest car anytime. Mt R500K is 107db on the standard exhaust and induction but i can get this down to under 98db with a raceco and a rearexit secondary silencer (at the expense of some power)

[Racer26]

Thank you everyone for your advise. It seems likely the car will not pass the noise test without mods which I will carry out before we take it to the track.
As an aside - I've owned the car since new for 26 years, and am ashamed to report a total mileage of just 6000. Its about time I used it properly! Stupid thing is - I absolutely adore the car, and intend to keep it forever!

[lyonspride]

Racer26 said:

Thank you everyone for your advise. It seems likely the car will not pass the noise test without mods which I will carry out before we take it to the track.
As an aside - I've owned the car since new for 26 years, and am ashamed to report a total mileage of just 6000. Its about time I used it properly! Stupid thing is - I absolutely adore the car, and intend to keep it forever!

Some of the Westfield guys running x-flows, have been swapping the standard silencer for used Motorbike silencers, the early YZFR1 for example. The alternative is a rather costly fully custom built silencer, which will weigh considerably more.

Personally, I think that people need to stop buying houses next to race tracks if they have a low tolerance for noise.