Which Exhaust do I pick

[Tiny]

Hi all, not far away now from registering my 66 GT Mustang Coupe and getting it on the road.  As I live in Victoria I'm not sure what exhaust (noise) will be acceptable.  I am going to fit a proper GT exhaust but I'm not sure whether to use the resonators or leave them off.  Will it get through a roadworthy without resonators?

cheers

[BAC]

As I live in Victoria I'm not sure what exhaust (noise) will be acceptable.

You should be able to get away with any exhaust you like.  Your car only has to comply with the ADRs in force at the time of its manufacture and there were no standards for exhaust levels in 1966...

[66RedRagtop]

RWC requires an effective silencing device so maybe check with whoever doing the test as to what will pass. Older cars used to have some leniency and may still have.

[BAC]

I can only find mention of having to be under a specific noise level to pass RWC for vehicles manufactured after 1988, but would be happy to see info anyone has that says otherwise.  In any case, how many RWC testers would have the appropriate sound measuring equipment?

Some testers may try to fail cars on stuff they are not technically permitted to do, e.g. still using the 'you need a new windscreen' bit when there are no significant defects in the driver's straight ahead view.  One tester suggested he could fail my car because the transmission cooler lines passed too close to the sump - WTF?

[shaunp]

I think the limit is like 80 or 90 db. In QLD if the police do a road side test  they test it at 2/3 rpm of max HP as stated by the manufacturer back in the day and also on over run to get the blow valve turbo guys

[Bucks]

96db is the correct sound limit for a pre 1982 V8, however the rpm should be set at 3300rpm
4 cylinders - 4000rpm
6 cylinders - 3200rpm

[SXTY8]

You could always try the trick we used when we had an unroadworthy sticker put on our cars because of a loud exhaust in the old days.
You get some aluminium mesh off a screen door, roll it up and insert it into your tailpipe.
It quietens the exhaust significantly and after a couple of days works it's way out and your sports exhaust is back again.

[BAC]

96db is the correct sound limit for a pre 1982 V8, however the rpm should be set at 3300rpm

Good info - is this available on the web anywhere to view?

[Bucks]

In my previous miss spent youth i think i had to do at least 4 of these tests issued from the EPA.
Yellow canary
It used to be on vicroads website, but iam not sure where to find it now.

[Tiny]

Thanks for all of the comments.  Based on the info supplied what are your thoughts, resonators or not.

[Gallop]

Have a read of this article which uses the Mustang as an example - http://www.americanmuscle.com/mustang-mufflers-and-resonators-whats-the-difference.html

I have a 65 GT Fastback (289 4 speed) with factory correct exhaust which includes resonators and trumpets. The exhaust note is not what I would call loud although the engine is quite stock.   My 66 (289 auto) without resonators is much louder but the engine has a few mods.

If you wish to install a 'proper GT exhaust' you will need the resonators - see http://www.scottfullerreproductions.com/1966_mustang_gt_w289.html

[Tiny]

Excellent information.  Thanks for taking the time.  Much appreciated.

Cheers

[Bucks]

 This is my mustang with no resonators, it sounds loud but passed a roadworthy 6 months ago, about 98db


https://youtu.be/X_x7es7FeSA

[Tiny]

Sounds nice.  What the drone?  Any drone at certain speeds?

[Bucks]

Not much drone, but mine is a 4 speed with a 3.5 diff ratio, so it fairly up in the revs at 110klm.

[Tiny]

Thanks Bucks, very nice looking car by the way.

which State you in?

[Bucks]

Thanks Tiny, I live on the Border, live in Wodonga Victoria and Work in Albury NSW (Best of both worlds)

[ND69]

Hey Bucks,
I was in your neighbourhood, the other day Mopars on the Murray, great weekend,

We stayed at the Padsteamer, It was entertaining watching the cars cruise up an down the main drag at night

[Bucks]

I went with my Local car club to check it out, as i do every year, a very well planned event, plenty for everyone to do and free kids rides and face painting makes it so much easier to do this sort of thing with the whole family.
It was amazing the only car that crashed during the weekend was a brand new VF commodore trying to show off to the mopar fans.