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Gunson colortune follow-up

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I received the Gunson Colortune yesterday and tried it out today. I found the front carb too rich and easily adjusted to Benson blue to match the rear one. Exhaust sound evened out and drove very well. No need to remove the air cleaners or use the Unison or tube to ear. It was easy to use (in the dark garage). I like it!
 
tahoe healey said:
I received the Gunson Colortune yesterday and tried it out today. I found the front carb too rich and easily adjusted to Benson blue to match the rear one. Exhaust sound evened out and drove very well. No need to remove the air cleaners or use the Unison or tube to ear. It was easy to use (in the dark garage). I like it!

I believe the kits are sold in MM?
What kit did you get for the BJ8?
 
AUSMHLY said:
tahoe healey said:
I received the Gunson Colortune yesterday and tried it out today. I found the front carb too rich and easily adjusted to Benson blue to match the rear one. Exhaust sound evened out and drove very well. No need to remove the air cleaners or use the Unison or tube to ear. It was easy to use (in the dark garage). I like it!

I believe the kits are sold in MM?
What kit did you get for the BJ8?

Yikes, I'm quoting myself!
Sorry, not clear with...MM I guess.
I believe the kits are sold in MM, as in millimeter size.
What millimeter size (kit) is the BJ8? (Moss does not tell you)

Clear as mud now?
 
Hey Tahoe,

Does the color change much from idle to say 2500 rpm? Meaning if it was lean, did it show lean over the rpm range?

thx,
Ken
 
Roger, I thought you meant Moss Motors. Most cars are 14mm. Go on Ebay and watch the video the guys in the UK have on their sight. You don't need the tube attachment on the first 5 cylinders. I helps on number 6.
Ken,I checked the changes with increasing throttle. Went rich for a second then back to nice blue. I am at over 6500 feet so we run leaner up here and I enrich when at sea level on longer trips. I did not check at a constant higher RPM. Probably something I should do. I was mostly concerned about balancing one carb against the other.
 
tahoe healey said:
Roger, I thought you meant Moss Motors. Most cars are 14mm. Go on Ebay and watch the video the guys in the UK have on their sight. You don't need the tube attachment on the first 5 cylinders. I helps on number 6.
Ken,I checked the changes with increasing throttle. Went rich for a second then back to nice blue. I am at over 6500 feet so we run leaner up here and I enrich when at sea level on longer trips. I did not check at a constant higher RPM. Probably something I should do. I was mostly concerned about balancing one carb against the other.

Rich, you are correct, Gunson has a full range of millimeter sizes, hence why I asked what the correct size is for the BJ8. I will assume, for you did not say outright, that the size for the BJ8 is 14mm. Please correct that if wrong.
 
TH,

You have inspired me to buy one and stop guessing if I have it right. While hard to justify in a good running car, I have an ebay auction selling a Carroll Shelby autographed toy car ending today, whose funds will be used to buy my very own colortune. And buying it for $49 delivered looks like the best deal out there.

ebay link
 
Why are the kits specified in MM (millimeter) sizes?
I understand the kit for the BJ8 is 14mm.

The sparkplug I'm using is a Champion RN12Y, which uses a 13/16 socket.
I believe one removes the sparkplug and replaces it with the Gunson sparkplug.

The Gunson sparkplug need to have the same thread as what the Heaely takes.

What reference is to the 14mm?
 
I believe 14mm is the diameter of the thread of the plug hole, not the size of the socket used to install the plug. The other plug size is 10mm, only used in lawnmower and (some) motorcycle engines.

AFAIK, the plug is the only metric size on any Big Healey, and I don't know if it's consistent with other metric threads WRT pitch, angle, etc.

There must be a story behind this, as AFAIK this size plug was standard long before metric was employed by any non-European countries.
 
:iagree: The 14 mm is the plug thread. In addition to the 10 mm, in the "old days" some plugs had pipe threads.

The only other metric threads I've found are the the Smith's speedometer input, which is 12 mm x 1.0
 
Thank you Bob and John for taking the time to answer my question. I appreciated it!
Cheers,
Roger
 
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