performance ac 1981

Big lumps of metals and spanners.

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skins
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performance ac 1981

Post by skins »

yesterday timed engine and changed dodgy ht leads and balanced carbs - seems now to tick over fine and runs ok :) - although when throttle increased there seems to be a slight darkening of the smoke, not by much just slightly - also the accelerating performance is not as good as I think it should be.
Any ideas?

Would adjusting the bypass and idle screws on the top of left carb impact on the cars performance when accelerating?

cumbriankeith
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PDSIT 3/4s

Post by cumbriankeith »

In effect the engine has a separate idling circuit integrated into the left carb, which continues to operate whatever the engine speed, although it contributes little at higher revs in proportion to the other jets that come in to play once the throttle butterflies start opening.
Keith
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skins
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Post by skins »

recently i had to replace the diaphram on both carbs - the metal notch on which was slightly smaller than before - i have adjusted the accelerator rod/screw which sits below the carb i.e opened the spring slightly - this now seems to be near its max - but still there is a touch of dark smoke coming out at higher revs - if i open the throttle setting slightly and reduce the idle mxiture on both carbs would this have the desireed effect of getting rid of the slight colour in exhaust fumes and increase performance - or is this just not related?
cheers
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Rozzo
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Post by Rozzo »

its not related m8,,, the engine uses different jets at idle.
silly question but you are giving time for the chokes to go off aren't you? and how good is the air filter? try removing the air filter element and see if that helps. if so buy a new genuine one. (some cheaper pattern ones altho physically the right size can have different airflow characteristics.)
good luck with it :lol:
LT owner and positively rattling around with the new found space
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