107db @4.5k RPM

[octanetorque]

Got the car sound tested at Castle Combe yesterday (it was my day off and I fancied a drive)

Clearly the car is quite loud and would account for my navigator's moaning on the way to Le Mans...

Any suggestions for silencer brands, types, placements etc?

I need to get it to 90db so I can take it on track - which is a shame as I LOVE the immense sound it makes when tunnel blasting.

Are we allowed bypass valves? Y pipe from engine, with sliding valve to channel exhaust through either more silencer or lesser silenced pipe?

Thoughts, photos and examples welcome!

[griff 200]

you will need one of these made I believe by the folk who made the speed 12 replica. It's well made and not pricey if I remember rightly. I have handmade two tail pipes one straight through one with built in inner mesh but still not proven if this will work. Richard

[Sonus]

Video needed

[LLantrisant]

such a bypass dose not help decreasing the noise level.

ok...lets start:

induction noise: use a proper air (filter)box

exhaust: how many silencers you have?


how old are they? (the older the more they loose the noise damping)
side exit or rear exit?


for track use you can try this one:

http://www.demon-tweeks.co.uk/motorsport/universal...

and this one:

http://www.demon-tweeks.co.uk/motorsport/universal...

[griffdude]

How old is the packing in your silencer box(es)?

I cut mine open & repacked them with this E-glass stuff & dropped the dbs by 8.

http://www.btbexhausts.co.uk/section_details.asp?S...

Alternatively, BTB can manufacture an exhaust that will meet the regs.

I have a set of ACT track day can's for 'emergencies', but they're a last resort as they sap power.

[Adrian@]

This


Adrian@

[gacksen]

have currently the same prob with my datsun at 118db at 3500rpm.
will put a second silcener in the system.

anybody jas experience with the supertraps ? just need to get it down to 90 once regardless of power output. if it will loose 50 horses no prob.

any suggestions ?

[octanetorque]

Adrian@ said:

This


Adrian@

I'd really like to avoid that if possible!!

[griff 200]

[quote=LLantrisant]such a bypass dose not help decreasing the noise level.

Little bit patronising!!!! It's a bypass valve to bypass a box in the system so he can have a nice track day silenced system them at the flick of a switch blast through tunnels!!! Is that not what was asked. Richard

[octanetorque]

griff 200 said:

you will need one of these made I believe by the folk who made the speed 12 replica. It's well made and not pricey if I remember rightly. I have handmade two tail pipes one straight through one with built in inner mesh but still not proven if this will work. Richard

This looks like what I'd like...

LLantrisant said:

such a bypass dose not help decreasing the noise level.

ok...lets start:

induction noise: use a proper air (filter)box

exhaust: how many silencers you have?

how old are they? (the older the more they loose the noise damping)
side exit or rear exit?

Induction - its a steel mesh one - I need to change that anyway.
Exhaust - One long one (and a silencer) that looks like it might be off an MGB

griffdude said:

How old is the packing in your silencer box(es)?

unknown!

Thanks for all the responses! I'll certainly look at these options and Sonus I'll get you that video soon... I miss six cylinders but the 4 does more then enough!

[octanetorque]

griff 200]Lantrisant said:

such a bypass dose not help decreasing the noise level.

Little bit patronising!!!! It's a bypass valve to bypass a box in the system so he can have a nice track day silenced system them at the flick of a switch blast through tunnels!!! Is that not what was asked. Richard

YES - ^^^^ THIS ^^^^

[octanetorque]

Swung by LongLife Oxford yesterday to give them a look at my undercarriage...

£250< will get me the bits I need - probably new baffle material; and they're happy to do screamer pipes with butterfly vales...

I'll update when I bite the bullet (gotta save up beer tokens)

[griff 200]

Good all sorted then.

[Fiscracer]

I would suggest you talk to Kevin at Zero Exhausts in Kent. His exhaust cut noise but don't cut power unlike most of the others.

[pete.reeve]

Fiscracer said:

I would suggest you talk to Kevin at Zero Exhausts in Kent. His exhaust cut noise but don't cut power unlike most of the others.

+ 1

http://zeroexhausts.co.uk/contact.htm