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Perfect for setting mixtures on twin SUs, especially if you use two colourtunes.

Rog.
 

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I'm Not Jed Clampett
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Never used one, mostly because I can't see how they would reliably set anything other than the tickover mixture. Revving a car in the driveway doesn't tell you anything about what the the mixture will be when the motor is under load.

Even if it was used under load on a dyno or on the road I can't see how the colourtune plug is going to give an accurate mixture indication when it's unlikely to match the heat range of the rest of the sparkplugs in the car.
 

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Discussion Starter · #4 ·
Perfect for setting mixtures on twin SUs, especially if you use two colourtunes.

Rog.
I havent used one since I was about 23 but set some MGB"S twins last week! Superb lil tool :tup:
 

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Discussion Starter · #5 ·
Never used one, mostly because I can't see how they would reliably set anything other than the tickover mixture. Revving a car in the driveway doesn't tell you anything about what the the mixture will be when the motor is under load.

Even if it was used under load on a dyno or on the road I can't see how the colourtune plug is going to give an accurate mixture indication when it's unlikely to match the heat range of the rest of the sparkplugs in the car.
With SU"S each carb has only has one variable jet,so in general terms if the sleeves and needles are in good nick the whole rev range is generally accurate after the carbs are set when at idle! Its a far more accurate tool than a gas analyser where you only get an overall reading from the two carbs combined when one carb running lean may compensate for the other running rich.
 

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Lost in the ozone. . ....
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Had one when I got my second car, seen them for sale at Frost.co.uk

BTW second car was the Riley 1.5, twin SU´s.
 

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I'm Not Jed Clampett
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so in general terms if the sleeves and needles are in good nick the whole rev range is generally accurate after the carbs are set when at idle!
Absolutely true if your motor is bog standard with a standard air filter & exhaust. I've tuned lots of cars with twin or triple SU's never needed anything other than the lifting pins for setting the mixture on standard motors that have SU's.

For anything modified, I'd be putting the cost of a colourtune towards some rolling road time, which has always been the cheapest BHP I've ever bought, not to mention the fact that the car's road manners will usually be vastly improved too.
 

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i've got 4 sets i use on my Y.. rover v8, quad dellortos, i can set up the idle mixture and carb balance on one bank in one go!

as the dellortos have fixed jets, they do the job great for me and i can see instantly which cylinder is out of adjustment
 

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Discussion Starter · #9 ·
Going to do the idle mixtures on my mates 302 with twin holleys at weekend,more accurate than a gas analyser....
 

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I havent used one since I was about 23 but set some MGB"S twins last week! Superb lil tool :tup:
The method i've always used in the past for setting up an 1800 B series is wind the jets flush with the bridge, back off the jet adjuster 2 1/2 turns, balance the carbs with an air flow meter then adjust equally until the CO meter reads 4.0% not forgetting to give the float bowls a couple of gentle taps with the back of a rubber handled screwdriver and a little rev to re-centre the jet after each adjustment.
 

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Discussion Starter · #13 ·
me and a mate just tuned his ford 302 with dual holleys today,the colour tune did its job,is now running as smooth as silk,what an invention! FV :)
 

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Hi All,

I have had a colourtune for about 25 years now and have found it to be a brilliant bit of kit for not a lot of money, ideal for setting up just about anything to get a good base line to work from.

With SU's, Stomberg's and fixed jet 40's etc i don't see the need for any other setting up colourtune works just fine inconjuction with a carb balancer.

Cheers.

Russ.
 

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Discussion Starter · #15 ·
Hey Russ,I tuned by ear an old MGB gt about six weeks back when the guy said his consuption had deteriorated to 14 mpg :shocked: using the old ear to to the tube and lifting pins way and then a couple of weeks ago with the colour tune. Not only has the owner been getting 4 mpg more after the colour tune treatment but the weather has got colder so he has been using more choke! So on balance there should be a 6 mpg improvement :happy: superb tool :tup:
 

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Hey cant aford 25 quid for a colortune now ive got my dyno and gas anyliser in the shed lol joking apart tested one of these against a gas anylyser in the 80s as a bet with my mobile crypton tuner mate and was spot on
 

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Discussion Starter · #17 ·
Hey cant aford 25 quid for a colortune now ive got my dyno and gas anyliser in the shed lol joking apart tested one of these against a gas anylyser in the 80s as a bet with my mobile crypton tuner mate and was spot on
hey fredrico,your rod will be the most fuel efficient 302 on the planet! forgot to tell you about the mgb,or did I? thats what gave me the idea in the first place :cool:
 
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