spider

iTrader: (1)

Afternoon all,

Friend of mine has convinced me to track the Scoob for the first time. It's Keevil airfield circuit, so nice & wide apparently with lots of run off areas.

Having looked at other threads, I understand the need for a helmet, and for spare brake pads, increasing the tyre pressures, etc. however, one thing I don't know is whether the exhaust will pass muster.

The trackday limit is 100db, so I hope my car will be within it - it's a completely decatted 3-2.5" system. PE T75 twin dump pipe, resonator mid section and original ScoobySport backbox.

Is there anywhere I can get it checked; don't want to drive there & find it fails!

Cheers,
Steve

andy97

iTrader: (1)

I have virtually the same setup except mine has a prodrive backbox. I dont think mine is that loud on tickover or gentle acceleration, but very loud on full throttle. How do they measure the sound, ie at tickover or higher revs?

R.B

I take it that its measured by a drive-bye if so I think you will be touch and go mate ?

Jim_B

iTrader: (1)

Most measurements are taken as static, 4500 RPM with a noise meter at 45 deg from the exhaust and a meter away [ or is it 0.5m ?? ] - cant remember. Not that many places do a drive by as far as I know.. Apart from Bedford autodrome.

Friend of mine with a full decat and H&S scoobysport b/b just scraped through with 98db

spider

iTrader: (1)

I think it's a drive-by measure so I'll have to be light on the throttle!

Friend says he may be able to borrow a noise meter - I hope so as I'd hate to miss the day.

R.B

Donnington is a 98db drive bye i ran my car with a rcm downpipe+centre pipe with a sti8 ppp backbox and was 106db the car is 400 bhp though.

R.B

SPEN555

R.B. Did you do a trackday at Donnington then? With that result did they boot you off track?

TaviaRS

Spider, It'll be a static test, 3/4 max rpm. Take it up to that very slowly, don't blip it.

If you can, see if you can borrow a bung (I know some Blitz systems come with them) for it. As an alternative, if you can't get one, make one - a sleeve over the outside of the exhaust (like a tin can, you get the idea) with holes drilled in it will reduce the noise level.

Yours will probably be about 98dB at a guess, based on my old black Skoda. As for testing, drive by the nearest police station and give it some beans - they'll do you a free test!

Jay m A

iTrader: (2)

100dB static is fecking loud! In fact its twice as loud as 97dB. Tell them max rpm is 6k for a start

spider

iTrader: (1)

Hello Jon - long time no see, how's tricks? Looking at the backbox, a baked bean tin might just fit over it! Compared to most other Scoobs, mine doesn't seem too loud (to me anyway), not sure I'll encourage the old Bill to take an active interest though ta!

Jay - I was hoping they have a high threshold as it's Keevil airfield - probably not got such sophisticated testing kit as a dedicated track. Good tip re the revs "No mate, it's a standard UK car - much lower rev range than the imports"! LOL

Cheers,
Steve

R.B

Yes but i changed the exhaust and went back on.

Im still trying to get an exhaust that is quiet enough but still has a good note.

Next week i will be testing an exhaust for RCM so we will see how that goes.

Just for reference there seems to be a big difference in noise level when you go from 300bhp to 400+bhp because of more airflow and fuel of course.

R.B

RRH

I've run many classics on track with h&s scoobysport decats and they all seem to be around 92-93db. My race car only shows 96.4.

Dip the clutch when doing the noise test as the transmission will create an extra 2 to 3 db.

RRH

Forgot to add- I have never run a car on track with a blitz or HKS etc system, which will probs be quite a bit louder, so couldn't make a judgement on that.

Very surprised at yours though RB???

SPEN555

When I was at Croft a few weeks back a TVR Cerbera had what looked like two tin cans stapped to the back of the two tailpipes with tiny holes in them. It was very quiet but also looked extremely resrtictive.