measuring noise levels how to?

[Bobfish]

Guys,

wanna do atrack day in the RX7 but not sure if ill pass noise regs. How and where can i get it measured? Does anyone know how de-catted and unsilenced cars generally get on for noise levels? Ive got a feed 80mm downpipe, ebay midpipe and 3.5 inch cat back. Standard ports.

Cheers

Carl

[Brett]

A lot will depend on where you intend to run the car, some tracks are very strict  You can buy a Db meter from RS or ARD, not normally that expensive either - at the end of the day, if you think its loud then it probably will be touch and go.

[shaunwil]

You can get a meter from maplins electronics for about 40quid. As said it depends on which track you want to run.

If you are going to donnington you need a friend to stand in a layby on a private road and you need to drive past at full chat. They have 3 or 4 monitering stations around the track manned by the council, buggers !!!

If your doing oulton park they tack a single reading around 5k rpm and then allow you out on track.

Its usually down to your backbox more than a silencer middle, some boxs can be run straight through, others can\'t even silenced in the middle.

Shaun

[Fish]

Carl, I\'ve just collected a centre section for testing (noise included). I\'ll post the noise levels once tested.

Current setup is a single turbo, straight downpipe, straight centre section (no baffle) and RE-A Dolphin backbox.

I will replace the centre section after taking noise tests, then after that replace with a racing beat twin pipe backbox.

Fish

[Habanos]

Not sure how this would work on my car?

If you rev the engine when the car is stationary it isn\'t overly loud, just sounds like it has a relatively quiet performance exhaust.

When driving and giving it some stick the noise changes completley, MUCH louder ( but in a good way ). Only way I can describe it is a "ripping sound". In a built up area it\'s border-line ridiculous!

That\'ll be the full Kakimoto exhaust then lol. Which is supposed to be regu92?

JB

[shaunwil]

You don\'t have a screamer pipe then ??

Shaun

[Habanos]

:Laugh  Doh!

[Fish]

OK just fitted the new centre section that I\'m testing and doesnt appear that boomey.

Meeting up with IainT tomorrow evening to get the noise levels, then will be fitting the Racing Beat backbox at the weekend and another set of testing then.

Fish

[Fish]

Met up with Iain, and he commented on the lack of drone at cruise.

Ambiant noise was around 74-76db, at 5000rpm is was sitting around 96-100db.

I\'ll swap over the backbox to the RB unit on Saturday and see what that measures at, but things are looking good.

Fish

[shaunwil]

Did you do a flyby run ??

Shaun

[Fish]

Might have done, but didnt take measurements at the time.

Fish

[Fish]

OK RB unit now installed and its even quieter, so it appears anyway.

No drowning at cruise which is an issue most mid sections suffer from.

Noise testing on Tuesday night at the southern pub meet.

Fish