Advice please - DB rating of my SI

Having had my S1 for a few months I am going on my first track day at Goodwood but I am concerned about my car falling outside of the 98db limit.

I have a S1 190 factory upgrade with the oval supersport exhaust. Do you think this will be OK.

Is there anywhere in hampshire I could go to get it checked?

thx

Graham

I have same spec car and I think you should be OK, 98db is a fairly common level for many circuits.

If you are borderline then it should be just a case of being gentle with the loud pedal and short shifting past the noisemeter.

Never done Goodwood but will one day, enjoy it.

is the cat still fitted ? or do you have a cat replacement pipe ? or an silenced CRP ?

Mine is 190 S1, CRP, Janpseed - 104 db. Not good for some tracks but sounds awesome

I think you will be borderline if the cat is fitted, & over if de-catted.

You’ll have do as Steve says, & keep your fingers crossed

Hope you have a great day

The Cat has been removed, so it would seem fingers crossed.

thanks for the feedback

Mine is 190 S1, CRP, Janpseed - 104 db. Not good for some tracks but sounds awesome

Is that a driveby reading and if so at how many metres?

I have the CRP and can pass a static test.

I guess we should have been more specific but the 98db is probably a static test, 45 degree angle and 1+ metres from the rear of the car. You will be asked to rev the car to a certain % of max revs.

is the cat still fitted ? or do you have a cat replacement pipe ? or an silenced CRP ?

Mine is 190 S1, CRP, Janpseed - 104 db. Not good for some tracks but sounds awesome

I would get it checked before you go to avoid disapointment … mines a 190 S1 with cat and Janspeed and it was 104 db static at Bedford last Friday - just got by on drive by by short shifting …

any ideas where I can get it checked?

I would get it checked before you go to avoid disapointment

not sure that helps…if you get a pass and then fail on circuit they will not be interested and if you fail and don’t go you loose your money. Just suck it and see, the guys at the circuit really dont want to fail you unless they really have to.


… mines a 190 S1 > with cat > and Janspeed and it was 104 db static at Bedford last Friday - just got by on drive by by short shifting …

do you have any packing left it that box?

Steve,

mine was static, 5500 rpm - but can’t remember if it was 0.5 m away or 1m away - think it was 0.5 m, but can’t be sure.

Think its supposed to be 3/4 revs. I believe some exiges only rev to 6000 rpm making the test done at 4500 rpm - sure I would be somewhat quieter at 4500 rpm rather than 5500 rpm.

Con McL.

is the cat still fitted ? or do you have a cat replacement pipe ? or an silenced CRP ?

Mine is 190 S1, CRP, Janpseed - 104 db. Not good for some tracks but sounds awesome

I would get it checked before you go to avoid disapointment … mines a 190 S1 > with cat > and Janspeed and it was 104 db static at Bedford last Friday - just got by on drive by by short shifting …

I’m with escaper, as I think Goodwood can be quite harsh.

Get yourself a soundmeter ( see here), or find somebody local with one. Where do you live?

Ian

Any of the sound meters in the links are only goind to be +/-3dB at best. How many would be annoyed to be “banned” for being 1dB over the limit ?

Lab standard sound level meters (SLM) at +/-1dB are mucho money. It costs thousands to get an accurate SLM. This is what makes a bit of a joke when people are kicked off for being, say, 0.3dBover some arbitary limit. You can get more variation than that just by repeating the test.

To put it in perspective, +/-1dB is JUST ABOUT detectable in an anechoic chamber (ie lab conditions). To get outdoor, drive-by measurements within 3dB is having a laugh.

Even though they’re only a few �10s, they’re still only a ball park figure. A complete waste of money, IMHO. I tried some measurements with a lab standard SLM at a recent MLOC rolling road session and found pretty wide variations in the results.

I reckon your best bet is to go with the car as you want to drive it and have something up your sleeve (ie put the cat back on) in case you get pulled off.

Well the kit used at trackdays is not much better quality than mine and the figures given are similar, so I don’t consider it a waste of money at all.

I check mine before a day and take it with me in case I get any problems.

Ian

Thanks everyone. Some interesting views.
I’ve taken the day off work but the good news is that someone else is paying…so I will go along and see what happens.

IDG … i live in Hedge End nr Southampton

A bit of a shlep up to Basingstoke then.

Ian

Thought I would let you know that somehow the car registered only 94db. This was 4db less than a mate of mine with a bog standard S2 Toyota lump.

They wanted me to run it at 5750rpm.

I played the “novice” card and very steadly ramped up the revs as slow as possible until he got bored and took the rate at about 5000.

I had a great first track day. Goodwood isn’t very forgiving if you get it wrong is it. Main aim was to bring it home in one piece and have some fun.

thanks for the advice - now to check out the rattles that have started and book my next one.

Graham