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Front carburetor

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In my opinion the front carb is ported most directly to the front 3 cylinders and the back is ported to the back 3 cylinders but the intake manifold is interconnected for the purpose of balance. I know if I adjust my carbs such as leaning out the front carb I will see it mostly in the front 2 cylinders with the 3rd cylinder showing somewhat of the interconnected mixture, meaning it is affected somewhat by the rear carb as well.
 
I have a Gunson Colortune and need to know which 3 cylinders are for the front and which 3 are for the back carbs.
 
AUSMHLY said:
I have a Gunson Colortune and need to know which 3 cylinders are for the front and which 3 are for the back carbs.
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BJ8,

which cylinders does the front HD8 carburetor manage?​

Front Carb: Clyn=#1,2,3-Yeah It aint no Daimler---LOL
 
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AUSMHLY said:
I have a Gunson Colortune and need to know which 3 cylinders are for the front and which 3 are for the back carbs.
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If you're going to use the Colortune, you should have two - one plug in #2 and one in #5.

There's tons of discussion of colortunes vs other tuneup methods if you search the archives. I've used them for years and am not really satisfied. Some have said ethanol screws up the colors.
 
Because of the balance port in the manifold, all carbs affect all cylinders to some degree - as vette says, the front carb would have it's biggest affect on the front three cylinders but will affect the rears too, just to a lesser degree.

I believe this is why both jets should be down the same distance from the bridge and both carbs should have the same air flow at idle and more importantly, off idle. Then, if everything else is correct, you theoretically have the same a/f mix and volume in all cylinders = smooth running engine.
 
red57 said:
Because of the balance port in the manifold, all carbs affect all cylinders to some degree - as vette says, the front carb would have it's biggest affect on the front three cylinders but will affect the rears too, just to a lesser degree.

I believe this is why both jets should be down the same distance from the bridge and both carbs should have the same air flow at idle and more importantly, off idle. Then, if everything else is correct, you theoretically have the same a/f mix and volume in all cylinders = smooth running engine.
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YES Red 57 that is correct
 
Michael, the Jag XK engines number their cylinders backwards. 1 is at the back and 6 is at the front. Don't know if they use this system on any other engines, modern or vintage.
 
CraigC said:
Michael, the Jag XK engines number their cylinders backwards. 1 is at the back and 6 is at the front. Don't know if they use this system on any other engines, modern or vintage.
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Thank you Craig for clarification here , Yes Daimler did too
 
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