TR6 Gunson Colortune

[bonzocfi]

I just bought the Gunson Colortune and was wondering if anyone else has used this device. Did it work? If it does, do I still need to get the sync tool? Would like to hear your thoughts on this product. Thanks!

 

[SASSAMON]

bonzocfi,

The color tune worked for me.

The synchronizing tool {Unisyn or piece of hose and ear) is also needed as the carbs must adjusted so that they flow equally.

When tuning the engine the carbs need to be balancced first then the mixture adjusted with the color tune.

I have two color tune units and use one for cylinder 1 and one for cylinder 3. This I find to be easier for me, as I don't have to swap the color tune between cylinders while tuning.

 

[Geo Hahn]

I also use 2 Colortunes - but on my 6 cylinder (2 carbs) I put them on #1 and #6 on the assumption that minimizes the effect of the 2nd carb on each reading. No idea if that assumption is valid.

As noted, syncing the carbs is a whole 'nother process and must be done before the mixture is adjusted. The balancing (or syncing) of the carbs is more of a mechanical adjustment than a tuning issue, thus it can be done on a cold engine, no need to wait until it is warmed up. In fact - if you could connect a huge electric motor to the engine and spin it you could sync the carbs -- as all you are doing is balancing the air pulled in by the intake strokes.

I use a Uni-Syn though some use a hose and do it by ear. You can even use a homemade manometer. If I were buying a tool for this today I would consider a gauge type tool (Air Flow Meter) just because it looks easy to read with some precision.

FWIW - mixture is one of the last steps when I tune. Generally it goes: valve adjustment, points gap, timing, new or clean plugs, sync, mixture and idle speed.

 

[Bruce100]

^this. To see why, adjust your timing while watching the colortune. You will see the whole range of colors as you do if all else is right. Color is a function of complete burn. If your ignition is untuned, you will have an incomplete burn and the color will be yellow, even with the carb set perfectly.

 

[bonzocfi]

Thanks so much for your inputs gents.

SASSAMON : Just bought the carb sync - thanks. Just bought one colortune for the time being. Wan't to make sure it works before I spend another $50.

Geo: Thanks so much for the "batting" order. You must have ESPN because that was going to be my next question!

Bruce: I'll do that. Thanks for the tip.