Originally Posted by Warmacht
I have a 85 cj with the 6cyl 4 speed stick. The OG carb died so a redline weber is what I want to go with. My questions are . What jet sizes for primary,secondary& idle at sea level . Also will the vac port for the distributor be fine with a stock vac advance ? Thanks for all the help.
The "typical" jetting below 3800 feet is this:
Primary Idle .75mm
Secondary Idle .60mm
Both Mains 1.40mm (or, P 1.40mm S 1.45mm)
Primary Air Correction jet 1.70mm
Secondary Air Correction jet 1.60mm
With the stock ignition Duraspark, timing is 8-10 BTDC (some say 10-12 BTDC) with the "S" ported vacuum source to the right of the choke housing down toward the mounting flange.
Some like the manifold vacuum for the advance. Initial timing would then be 8 BTDC, then the manifold vacuum hooked up and it will go off the scale. (22 BTDC ?)
Do not allow your engine to "ping", pre-ignition is cumulative, meaning every ping adds up to the big bang.