Thread: 48 IDF jetting.
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Old 07-03-2009, 02:42 AM
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Quote:
Originally Posted by Caprimaniac View Post
After testing on a proper situation (autoslalom- between cones on a track) , I found the middle/ transition to be too rich.

To make things better, can the nuts on the acc.pump shafts be turned innwards (from the valve covers towards the carb- body)?

Can the large idling jet (65) be causing this trouble? (Transition holes are fed by this jet ...)

Or can the 0 (closed) acc.pump bleed be part of it?

Also; after reading an older post by JacMac I've found a probalbe cause of two barrels unwilling to be synchronized; twisted shafts!?!

I'll look into things and hopefully things will get even better....
Turning the nuts in gives more volume.

Maybe try a 60 idle and a 35 pump bleed, one at a time, idle jet first.

The idle/transition/main circuit all need to overlap and provide a smooth blending A/F of mid to high 13s, the accelerator pump should then provide the minimum to prevent a stumble at any rate of throttle opening, any more is too much, then the engine recovers from being overrich, soggy throttle response.
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