Stock exhaust and J tube compatibility

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Moseley

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Hi folks,

I’m looking to remove the Vintage Speed exhaust from our bus and replace it with a standard system; obviously this will mean changing the J tubes as well. Long story short, but our dog suffers with journeys in the camper, and I think it is down to the noise. So I’m looking for the best solution to quieten it down as much as possible (retaining the tow bar) even if it means a reduction in power.

The obvious solution is a stock exhaust, unless anyone has any other suggestions! However, I’m confused by the various J tubes on offer. I’d much prefer paying extra and going for a stainless steel J tube, and looking at the likes of CSP, they offer a wide range of diameters. Does anyone know if they’re all compatible with a stock back box as I can’t find anything on any website? I’m wondering if any non-flanged J tube would be suitable, but would like to know for sure before ordering.
 
A stock exhaust is going to be the quietest option.

They can use J-tubes of the "standard"/narrower diameter and don't need flanges. The end that connects to the exhaust box is basically a straight pipe!

Is your engine [fairly] stock?
 
A stock exhaust is going to be the quietest option.

They can use J-tubes of the "standard"/narrower diameter and don't need flanges. The end that connects to the exhaust box is basically a straight pipe!

Is your engine [fairly] stock?
I had noticed the slip-in connection of the standard system, but wasn’t sure how the two parts actually mate together.

Engine is an 1835, 100 cam, twin 32s, so nothing mad, but around 90hp from memory. I’m fully accepting that I will be sapping power by swapping to standard!

These were the options from CSP, I thought at least one of those would mate to a standard silencer, but there’s no clues on their website. Failing someone having an answer I’ll speak to CSP directly. There seems to be quite a few options out there for J tubes from different brands, but unless I’m missing something, I can’t see any pointers towards compatibility with the silencers.

https://www.csp-shop.com/en/exhaust-heating/j-tubes-csp-257-100-035-25922b.html
 
The fitting clamp is the same as the one that's used for the tailpipe e.g.

111298051_1_97703627-199A-420F-9494FD523170494C.jpg

A stock zorst will restrict your larger engine, but the puppers comfort wins all! 🐶

A scan on VWHeritage suggests the OD of stock J-tubes is 35mm (example here)
 
If you are going back to stock you could fit heat exchangers (even s/h imports) and have a warm bus😉
 
If you're going stock silencer you'll need to match the port size with the J tube. Just buy a pair of "stock" J tubes.
Thanks, I think some of the pictures are misleading as they show larger diameter J tubes, but with a tapered end suggesting that they’d mate to a stock silencer. There doesn’t seem to be much info in the text of the ads to suggest what is compatible with what. I suppose what I’m trying to get to is understanding what stainless steel J tubes are available for a stock system, as there’s loads out of stock, presumably because of supply chain issues.
 
Thanks, I think some of the pictures are misleading as they show larger diameter J tubes, but with a tapered end suggesting that they’d mate to a stock silencer. There doesn’t seem to be much info in the text of the ads to suggest what is compatible with what. I suppose what I’m trying to get to is understanding what stainless steel J tubes are available for a stock system, as there’s loads out of stock, presumably because of supply chain issues.
Just kampers sell stainless steel j tubes which work with a standard exhaust. I fitted a set last week to a customers bus.
 

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