258 Weber Carb and engine knock

Dauntless

New member
Hey guys need some advise here. I bought a my third non-running cJ-money pit a short time ago. Many of you know what i mean ( primer paintjob, engine parts in old boxes, 10 years of neglect, no windshield, shot wiring, no dash...) well few shocks and skinned knuckels later its ugly and on the road. Its an 1985 cj7. Wouldnt idle (or start sometimes) because of whole BBD mess so i did a nutter bypass and installed a weber 34/34 carb and it started first try. Problem is I get engine knock under load (hils mostly). I cant seem to jet the timing right. If seen factory rec's for motorcraft carbs around 6 BTDC but the nutter bypass site (whick uses the BBD in the example) says about 12 BTDC. I called Weber but was just told that they dont have a set recomendation. The knock decreases with a rich fuel mixture but milage goes down to 10mpg!:cry:
I still use the stock ignition so if your recomendation included an ignition upgrade-which type? Capacitive dischard MSD style or an HEI conversion?
thanks

Scott Mead
1970 Cj5 V6
1895 Cj7 258
1990 Xj 4.0
 
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