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*Sharps40* · 04-22-2013, 08:10 AM

I made four fine adjustments of the fuel mixture and idle speed (hot and with test drives) this weekend after my Friday evening correction of initial advance from 10 BTDC to 15 BTDC.

The truck performed a bit better each time. This morning's 40 mile ride to work was confirmation that I may be moving in the right direction.

Today's set up was further leaned out. The Weber DGEV is now exactly 2 turns rich from Zero and just a bit less than 2 turns in from first contact for idle speed (now 600 RPM), retaining 15 BTDC.

Over the weekend, the leaning out adjustments provided a considerable reduction in 1st and 2nd gear deceleration popping. In addition, the transition and use of the secondary at highway speeds remains smooth and free of flat spots and hesitation. There is smooth power on the top end and the pulling ability on the bottom end is improving. Pushing 70 mph today and the engine felt like it had more to give...a feeling that wasn't there on points and a leaky Model B.

I'm going to leave the carb settings alone tonight and try adding a bit more ignition advance. I'm at 15 BTDC and note in Mr. Langdons HEI instructions a recommendation for 18 BTDC. I'm hoping this will slightly smooth and increase the idle speed allowing me to leave the idle screw alone. With luck the additional advance will bring in a bit more power on the bottom end, coming closer to what I remember the Rochester B set up having before - but in any event I believe we are homing in on the right settings!

I need to find good instructions for setting the choke/cold idle on this Weber. I have the cold idle at 1400 RPM based on the relevant screw. However, as soon as I touch the pedal, it falls to hot idle speed (600 RPM) and is rough or stalls if not fully warm. Should I be rotating the black choke housing at this point? (my thoughts were until fully warm, a touch of the pedal would reduce the RPM below 1400 but not all the way down to hot idle speed of 600 RPM.)

In any event, it seems I'm gettin closer and closer to very satisified with this carb and ignition system. It may well be that Mr. Langdon at Stovebolt does in fact have all the "Magic Smoke" for this application!

04-22-2013, 08:10 AM	#168
Sharps40 Account Suspended Join Date: Oct 2012 Location: here Posts: 2,408	Re: The Official John Lee Jr Thread I made four fine adjustments of the fuel mixture and idle speed (hot and with test drives) this weekend after my Friday evening correction of initial advance from 10 BTDC to 15 BTDC. The truck performed a bit better each time. This morning's 40 mile ride to work was confirmation that I may be moving in the right direction. Today's set up was further leaned out. The Weber DGEV is now exactly 2 turns rich from Zero and just a bit less than 2 turns in from first contact for idle speed (now 600 RPM), retaining 15 BTDC. Over the weekend, the leaning out adjustments provided a considerable reduction in 1st and 2nd gear deceleration popping. In addition, the transition and use of the secondary at highway speeds remains smooth and free of flat spots and hesitation. There is smooth power on the top end and the pulling ability on the bottom end is improving. Pushing 70 mph today and the engine felt like it had more to give...a feeling that wasn't there on points and a leaky Model B. I'm going to leave the carb settings alone tonight and try adding a bit more ignition advance. I'm at 15 BTDC and note in Mr. Langdons HEI instructions a recommendation for 18 BTDC. I'm hoping this will slightly smooth and increase the idle speed allowing me to leave the idle screw alone. With luck the additional advance will bring in a bit more power on the bottom end, coming closer to what I remember the Rochester B set up having before - but in any event I believe we are homing in on the right settings! I need to find good instructions for setting the choke/cold idle on this Weber. I have the cold idle at 1400 RPM based on the relevant screw. However, as soon as I touch the pedal, it falls to hot idle speed (600 RPM) and is rough or stalls if not fully warm. Should I be rotating the black choke housing at this point? (my thoughts were until fully warm, a touch of the pedal would reduce the RPM below 1400 but not all the way down to hot idle speed of 600 RPM.) In any event, it seems I'm gettin closer and closer to very satisified with this carb and ignition system. It may well be that Mr. Langdon at Stovebolt does in fact have all the "Magic Smoke" for this application!