Exhausting

[Guest timswait]

After scraping through the SVA test with the standard RHE exhaust and lots of iron wool it seems like time for something a bit quieter. (it seems a bit silly having to put ear plugs in before embarking on a long journey and I want to be able to enter Curbourgh this year). Has anyone had good exhaust systems, and how about the RHE stainless 4 into 1, is that any good?

[Guest Angel Boy]

As a cheap upgrade form the twintube set up it maybe the way to go, but it ain't anymore refinded (on my it isn't anyway) form the noise point of view. I am getting the engine tuned this weekend so that might make a difference. Will let you know.

 

Andy

[Big Jim]

I have the larger of the Custom Chrome silencers fitted, they are much quieter than the RH one, and are repackable (about £10) but they suffer from the constant hammering of road *bleep*e flung up at it from the front wheel, I can no longer get that part remotely looking clean, never mind shinny. After fitting the Vauxhall motor, I have found that it's not as quiet as it was with the Pinto. I was hoping to talk to the "Wunoff" (spelling) gang at Stoneleigh, but they didn't make an appearance.

[Guest timswait]

How's this for an idea:

Could it make my own glass packed silencer out of the RHE one? If I cut the box open, add a wire mesh tube down the centre of the silencer and fill the space between the mesh and the rest of the box with fibre glass loft insulation would this work? It should let the exhaust gases down the centre un-hindered, but the sound waves will be deadened by the glass, as I understand it this is what a glass packed silencer is anyway. I've attached a diagram, don't know if it will work.

[Big Jim]

That is exactly what a silencer is.

[Guest Julian B]

Hi

 

If you have the standard exhaust manifold and you use the kit supplied exhaust system you may well find that changing to the 4-1 system a bit of a job. Alternator, servo, steering column and brake pipes may need to be relocated. The side panel exit may need enlarging too. Its a lot easier to build the car around the 4-1 than it is to retrofit.

 

I did change from the standard to the 4-1 exhaust system and used the custom chrome silencer. It passed the sva ok but i wouldn’t call it quiet and it was measured up around 98db (i think) on the test. The plus side is that the engine power goes up noticeably which makes all the work worth while.

 

Julian B

[Guest Richard Keyse]

A few years ago I had the honour of the loudest kit car possibly in the country-measured at 117dB at Castle Coombe. The scrutineer said I had an amplifier not a silencer. I had difficulties seperating the two halves of the system so I put up with it. I am now also thinking of leaving it on the car and angle grinding an opening underneath and repacking it. It would be nice to hear how others have got on with different types of packing and methods of re-sealing the opening.

[Guest Greg]

FWIW

If you want some more info on repacking, there was a lot of discussion on the se7ens list some while back, ie how tight, stainless woool, sealing etc. I don't remember what the concensus was but it'll be in the archives. As for sealing high temp silicone, for sealing flues will keep it gas tight if you fix the edges of the new cover with self tappers or drill and tap for 5mm stainless button headed cap screws, it shold be removeable next time it needs restuffing.

 

Greg

[Big Jim]

I've just been in touch with Wunoff silencers, they have sent me details if anyone wants them, e-mail me off board so that I can attach them. they are offering it to club members for £150 inc VAT. that is very similar to the Custom Chrome one. They also say that the noise level will be under 110 db for whatever engine.

incleds the input pipe & brackets etc although not shown on the piccy.

[Big Jim]

I've now got the new Wunoff silencer fitted, and it's much quieter than the Custom Chrome one was on the Vauxhall engine, but it's been a *bleep* to mount. It does come with a pair of stainless steel clamp rings, that go right around it, but when I mounted it on those, and on rubber bobbins, you'd have need a drawbridge to get over it, I finally came up with another way to do it, and it's still mounted on the rubber bobbins.