Master Craftsman in all exhaust systems
The catalyser seems to be the most misunderstood component in the exhaust judging by the antics of some owners.
It's a common strategy to remove the substrate - this VX220 N/A owner is in the middle of doing this on the downpipe bolted to the manifold, hoping that he will release some bhp. Reducing the back-pressure innit! This one is a metal substrate and it's tough to hack it out. Unfortunately, where you really need the gas-speed to be at its highest, he's created a large void which slows it right down - not the best feature to encourage scavenging at the exhaust port.
All the Toyota-engined cars use the same body (mantle) and ceramic substrate for all the different motors - 4 & 6 cylinder.
Here is what the internals look like on the V6 motors which have them fitted -
You can see it's a very restrictive honeycomb - 600cpsi (cells per square inch).
The log manifolds (headers) on the V6 use these UTC's (Ultra Thin Catalysts) to help the car pass some very strict worldwide emissions tests.
The whole design is a serious block on power output and with increasing power outputs on each new V6 model, they are under a lot of supercharged stress. For instance - don't even think about retaining these manifolds on a TVS1900 install!
24/12/2018: Phew - what an end to the year! Very, very hectic. Never enough hours in the day. I usually ship 70% of my production overseas but this last quarter was 70% to UK owners! Been 'no-platformed' by the Seloc alpha bell-ends so it's not forum advertising. Maybe Absolute Lotus magazine has been the difference (it's a good read!) or maybe I just design/build better exhausts than the rest ;-)
Another supercharged V6 destroys its UTC's (Ultra Thin Catalysers) in the factory manifolds (headers). I admit my tongue was firmly in cheek when I brought out the Engine Protection Kit a few years ago - but as V6 power outputs increase with every new model - these kits are becoming ESSENTIAL. Haven't heard of any problems on the N/A motors though. Lower level of stress on these installs - unless you're on Track!
A LOT of 2bular V6 exhausts heading across the pond to the USA this month! Comforting to know that some owners in that part of the World know the difference between V6 N/A and Supercharged exhaust demands. I have supplied enlightened owners over there previously but those numbers are going to increase dramatically.
Check out the V6 comparison page for guidance/information on the exhausts. Still a lot to update there but you can never have too much information.