CV or CJ head/port J-Tubes replacement.

Is it easy to tell if the port is oval or square from the outside or do i need to remove the old j-tube first?

We suffered a hole in one of the j-tubes on Beau down past Bordeaux and returned slowly patching it up with baked bean tin pieces and jubilee clips.

I'm looking at replacing it/them with CSP J-Tubes
Second question is whether the trapezoidal ends all finish in stock positions so you could fit to another existing exhaust or does that mean youre committed to a CSP exhaust from that point onwards?

https://www.mecatechnic.com/en-GB/j-tubes-for-type-4-engine-78-by-2_KC26100.htm?queryID=fdf40b8c38bef34e9555b11c212f15fc&objectID=KC26100&index=mecatechnic_en&queryString=j-tubes&queryFacet=VW Combi Bay Window

 

Yes

You could get heat exchangers for the price of those J tubes. The flanges are in the original position so any exhaust will fit but a CSP Python is the best.

 

+1 for the Python and it works with heat exchangers

 

yes but heat exchangers are super restrictive and not really utilising the full benefit of the CSP .

 

Restrictive maybe but super restrictive? Not really, unless you’re trying to squeeze the last possible bit of power out of the engine. Heat exchanger work fine on my 2316cc engine - 34mm exhaust valve, to 38mm heat exchangers to 42mm Python primaries to 63mm after the collector.