Will I need the long reach adapter , G4055D , or will just the 14mm plug be ok ?
I didn’t need the adaptor, the standard kit works just fine.
I’ve read mixed reviews about this on here. Am also considering installing an o2 sensor and gauge. Any tips on effectiveness on either?
The Colourtune will let you get mix at idle pretty damned close. If the engine is stock, and you’re running the stock carbs/needles/air filter, then the Colortune is all you need. An O2 sensor and gauge is more accurate, and you can read it under load across the whole rev range.
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Andrew hit the nail on the head. I’m also thinking oxygen sensor or air fuel meter for the reasons Andrew states. I looked at Colortune, but agree that it would be useful for idle but not much else. Besides, I’ve gone full modern with my EDIS conversion (see my post in Saloons recently)…using an A/F meter would keep me on that path.
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Which can be done just as well, w/o the Colortune.
Cute toys, but without a rolling road…a toy.
A rolling road is a bit OTT for a hobbyist with only a single, or a few cars. An O2 sensor per carb (if your exhaust branching matches your carb branching) is already pretty expensive. The Colourtune is good enough for most of the users here (only a single, or couple of cars) who mostly haven’t spent years adjusting carbs.
We have a set of 4 Colourtune plugs, 6 would be nicer but we don’t see many 12 cyls.
When a car which doesn’t respond as expected to carb adjustment comes in we put a Colourtune per carb branch in. It’s a quick and easy way to see what is going on inside to be able to determine if there is something more than just a misadjustment going on.
Every now and then a “stinker” will appear, a car which is running so rich that you could collect the condensate at the exhaust and siphon it back into the tank. You know the kind, where your eyes begin to hurt before you’ve even recognized what model car it is. Rather than pollute the exhaust tester sensor we use the Colourtunes to get these cars back into the range of internal combustion first.
So no, not a toy, but rather a useful diagnostic aid.
I’ve found mine quite useful as an assist to setting the mixture. After I installed the adjustable jets in the ZS carbs I set the carbs first with a Uni-syn; if they aren’t balanced in the amount of air they are drawing you are wasting your time doing anything else. Once balanced I adjusted the jets until Iachieved the correct exhaust note as per the Owners Handbook, page 67.
“When the mixture is correct, the exhaust note should be regular and even. If it is irregular with a splashy type of misfire and colorless exhaust, the mixture is too weak. If there is a regular of rhythmical type of misfire in the exhaust beat, together with a blackish exhaust, then the mixture is too rich”.
I then verified it with the Colortune and it agreed I was spot on to darned close.
Finally I tried the lift the piston trick and got the results I was looking for.
Have watched a few clips on You tube , people using the colour tune , it’s amazing how simple a tool it is , you can see the diffrence straight away with the mixture , at tick over and at higher rev’s , It will do for me !
I’m running three WBO2 sensors, one for each carb. They’re hooked up to a datalogger, as you really need to see the trends in the mixture rather than immediate readings. At least on my car with a hotted 4.2 and fast road cams, the readings are in no way smooth. This method has helped sync the carbs a lot closer than any traditional methods has previously.
I never had any joy at all from the Colourtune.
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Definitely a good system, but we’re in different boats.
If someone brings me a car and says “Can you have a look at it?” I can’t really say “Sure, just let me remove your exhaust manifolds, drill some holes, weld some bungs in, run a bit of wiring, then find a space for the logger/gauge.”
What I can say is “Sure, give me a few minutes to check the timing and fit some colourtunes, then I’ll be able to say something sensible.”
Two different scenarios indeed. One the quick fix, the other the long term project. And indeed, the benefit, for me at least, was totally relative to the effort put into it. The Gunson could have been left in the box for all the good it did, while the WB02 setup revealed what a shambolic method of fuel delivery the old carbs actually are. Maybe I should have left it at the Gunson, eh? 
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I’ve recently used O2 sensor technology on two carbureted cars and found it to be highly useful. First off, it’s not hard to IDLE tune any SU car in sound condition with basic skills (timing, synchronization, richness) on ANY SU needle, and my color tune has remained unused since almost the time I bought it. I will add that I also find intake vacuum gauge to be a helpful tool in idle tuning. The rub comes when you translate that to operation under load. Still not too bad if you have a stock engine and use standard needles recommended by experts like Joe Curto. The rub comes when your engine is not stock. My xk120 is highly modified, running on 2" SUs, so all bets were off. Likewise my Morris truck with mods. By welding O2 sensor bungs in the exhaust pipe near the manifold, I was able to use off-the-shelf technology to verify my settings at idle and above. No, it’s not the exact 14.7 ration that your modern car computer uses, but it demonstrates that I am not too lean and not too rich, which is what destroys engines. It’s fascinating to watch the ratio over the performance range. I don’t have the budget for the “rolling road” either, but I can temporarily transfer my air/fuel meter to any of my cars for the cost of a metal bung and a bit of welding wire, and go for a drive.
So, my recommendation is to use basic tuning skills, listen and watch performance, and spend time reading your spark plugs after your drive if your car is pretty stock, to see if your needle profiles are good. If your car is not quite stock or if you are curious, try the air/fuel meter. Not so expensive, and not difficult. Good driving.
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Buy 2 and put them in positions 2 and 5. simple and quick. Andrew said everything else.
I would be interested in knowing where are your 3 sensors are located so as to measure a tri-carb set up ?
I’m running stainless headers, with 2 into 3 collectors, so easy to have a sensor per pair of carbs^h^h^h^h^hcylinders (corrected).
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You mean per pair of cylinders?
Yes. Sorry. Per pair of cylinders, one sensor per carb.
Well I got a Colourtune off e-bay , old but never used for just under ÂŁ10
Used it yesterday , soon as I took number 2 plug out I could see it was too rich , as the plug was a bit black and sooty
Screwed in the colourtune , and sure enough it was yellow !!
A few turns out of the mixture screw and it turned a nice blue colour , screwed it back down , to yellow again then out slow and stopped just as it was turning blue again , did the same on number 5 plug !
Then screwed them down 1/4 of a turn , best to run a little rich then weak .
It’s a great tool , takes the guess work out the job , took the car for a 20 miles spin all is fine
So I am happy 
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