Lotus Elan

Is a Colortune worthwhile

PostPost by: bill308 » Thu May 05, 2016 8:12 pm

Some issues to resolve:

1. What is the correlation between the blue/yellow transition point and A/F ratio or lambda?

2. What effect does % ethanol have on color?

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PostPost by: Elanconvert » Fri May 06, 2016 6:53 am

just to add ......

had a problem with another car on single weber......would idle ok but wouldn't rev......mechanic friend convinced me it was points/ignition timing........but fiddling for a while brought no improvement...
colortune clearly showed fuel starvation!!!

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1970 S4 dhc big valve
1973 Ginetta G15
1967 Ginetta G4 [sadly now sold]
1959 lotus elite type 14
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PostPost by: TroonSprint » Fri May 06, 2016 2:01 pm

When I finished my car last year I set the idling mixture on the Webers with a Colortune as per Brian Buckland's manual. It was easy to do and I have to say the car runs really well and can sit idling at around 1000 rpm all day long.
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PostPost by: billwill » Fri May 06, 2016 8:55 pm

I find that you cannot really set the balance between the carburettors until you have got the idle mixture approximately correct, so the colourtune is ideal for doing that.
Then twiddle the screw between the carbs to get the balance right. With one of these:

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