Master Craftsman in all exhaust systems

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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! 

Looking at the 4-cylinder motors, the later 2ZR motors seem to destroy their factory catalysers very quickly. Particularly with track use. If you look inside the factory manifold you will see the first Lambda sensor (the one that controls fuelling) has had to be shielded from the stresses of supercharged gas-flow.



If you can, it's always best to move the first Lambda sensor further down the pipe and use a wiring extension. Supplied with all 2bular 2ZR manifolds.



Same on the V6 installs. Getting rid of those log manifolds and their vulnerable UTC's (Ultra Thin Catalysers) is a great move for more power and torque and moving the first Lambda sensors to the downpipes means the sensors are not toasted so regularly. Whenever the factory manifolds/catalysers are removed, it's usually found that the first sensors and their wiring are crisped to perfection. I strongly recommend fitting new 1st lambda sensors when the 2bular EPK is fitted. You can see the 2nd sensors are fitted on the exit cone of the big HJS HD catalyser.



The owner of his new 111R was told he had a 2bular 4-2-1 manifold + catalyser already installed. Unfortunately, the catalyser wouldn't pass an MoT and he sent the offending item to me for appraisal. Sadly, he didn't have a 2bular 4-2-1 and he didn't have a 2bular catalyser. I was actually working on one of my catalysers when it arrived and took this pic - 



Those tiddlers (I refuse to call it a 'catalyser') were very popular with certain aftermarket suppliers a few years ago. Cheap and nasty pieces of kit - but some people are 'cheap' and thought they had bought a bargain!

A very irate supercharged 2ZZ owner contacted me recently. His 7 month old Hangar 111 catalyser couldn't pass its MoT. It's always difficult to tell by looking at a catalyser if it will 'work'. Only when it can't catalyse and fails an emissions test do you find that out - and then it's too late! Here is the Hangar 111 cat - 



Compare with the 2bular 2ZZ-GE catalyser - 



The first thing that leaps out at you is the large bore of the link pipe from the OEM manifold to the catalyser itself on the Hangar 111 design. It's 3" diameter! So when you're looking for a high gas-speed at the exhaust port, this large bore slows the gas-speed right down. Not good for scavenging and consequent damage to performance. Mind you - it's very easy to swage a 3" pipe out to the required diameter for the doughtnut gasket! That strange bent flange plate? No idea.

The 2bular design has a fully-welded flange which allows the same dimension as the OEM. So the springs have the same operating length. I use a reducer to bring the gasket cup down to 2.5" diameter - same as the rest of the system - maintaining a high gas-speed from cylinder head to tailpipe.




Looking at the other end of the Hangar 111 cat, it uses a 2.375" diameter pipe for the exit. If you want your catalyser to operate efficiently, you don't want such a big difference between entry and exit pipework. Hangar 111 have had to swage the pipe up to 2.5" to fit to the silencer entry.




As stated earlier, it's not possible to evaluate the quality of the actual catalysing substrate itself - and this Hangar 111 example failed its first MoT. I have been using the German HJS catalysers for almost 5 years now. A quality component with a good weight of the rare materials needed to actually do the catalysing. Expensive - but it will do its job for a lot longer than 7  months.

You see the 'HD' tag on the big 130mm HJS catalyser below? That stands for 'High Durability'. The 200cell metallic substrate 'brick' is hi-temperature brazed to the shell (mantle). During track or race use, a lot of raw fuel can hit that glowing substrate (over 600deg C) and the brazing can melt. The brick is now loose inside the mantle and the gas-pressure on a supercharged install can push it down the exit cone and it forms a very effective plug. Melted pistons follow very soon after.

If you look closely you can see three compression indents in the middle of the mantle. Used to be a single indent but now three. This feature can hold the brick even after the brazing has melted - and the catalysing continues. Very clever - very HJS.


























30/06/2019: Must admit to a heaving belly-laugh at the clowns on TLF. Ref the thread on "exhaust pipes differ in color". If you have a front-engined install the exhaust run through to the tailpipes is near enough straight back. Twin Titanium tips will have the same coloration. The hue depending on the HEAT they are dealing with. Lighter blue - hotter the pipe. However, on the Lotus V6 mid-engined install, the pipe run approaches the tailpipes from the right (looking from the rear of the car). So the LH tailpipe sees more of the gas-flow - hence the "differing color". You'll see it on the Titanuim tips fitted to the old Lotus Sport exhaust on early N/A cars. Can't remember anyone complaining about them then. What made me laugh were the comments/advice from the TLF 'experts'. Batteries/tin-foil/sugar!????  Blowtorch!  Send them back!  Ignorance rules on there folks - but it is entertaining.


29/06/2019:   I have clients with the full 2bular system fitted to their cars working with this firm to develop their stand-alone ECU's. I've never been convinced of re-flashes/re-tunes. Sometimes they work, sometimes they don't! Better to get rid of the factory ECU and have complete control with this stand-alone P'n P ECU.

Joe Taylor - 220Cup -  chose the full 2bular kit for his racecar. Working with RRR Engineering to develop their stand-alone ECU he has achieved excellent results and with a noise-compliant exhaust fitted.

Only chocolate wheel studs prevented a better performance -  but the potential is there.

Another client with a 260Cup (not many of those around!) running the full big-bore manifold + SDCP  - tuning by RRR Eng - has achieved close to 300bhp.

Supercharged V6 fitted with the 2bular EPK -  and lightweight system will be on the RRR dyno very soon.


17/03/2019: Brexit. Causing some panic with my EU customers awaiting their orders. The Germans seem to be very calm though - they think Mutti will sort it all out - hope so!

Never been busier and it's right across the board, from S1 K-series to Exige 430's. Only 2bular covers the whole market and only 2bular has FIVE different 70mm systems for the supercharged V6 installs. From LOUD to the QP (Quiet Performance) systems.

2bular and the Seloc and TLF forums; forums are just another form of social media these days. Long gone the reliable source of information with the community feel. Nowadays, I've seen a moderator on Seloc telling lies about me and posting defamatory comments about my business - that's the Seloc that I know!

TLF has a moderator (see a pattern developing?) stating that 2bular is sh*t. The owner Mr Andrew Betts (Bibs) isn't interested in abiding by his own Terms & Conditions. He's happy for anyone to post derogatory and defamatory comments about 2bular. I guess he needs the traffic. His statement that I'm "not banned at all" is mendacious. I certainly cannot post on TLF - that's a ban in my book. Anyway - I have many supporters in the Lotus World. I advise them to avoid posting in my defence - not worth the hassle. Best to find your car's Facebook page and keep in touch with like-minded owners that way.




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.















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