Quick background
440 .030 over. Around 11:1 CR
MP 509 cam
6BBL
727 with reverse manual
Used to have horrible overheating problems. That seems to be taken care of. Had timing issues. Again, seems to be rectified now. Timing is around 16 initial and all in around 2200 RPMs at 34. I don't remember exactly what the timing is. It starts fairly easy when hot and no run on when turned off. I was having what sounded like spark knock at WOT. Now it feels like it runs out of gas during WOT run after going through the gears. It falls flat on its face above 3500 RPMs in 3rd. Does great from 1st to 2nd. Can feel it falling off when I shift into 3rd.
Outboard carbs metering plates drilled by ProMax years ago
Rebuilt couple times with new gaskets last year. Twice.
Trying to get the carbs set. Main jets are 65 I believe. Power valve is 4.0. I think I should go up to 4.5 or 5.0. I was at the 5.0 but idle was really rich. Burn your eyes rich. I could lean it out a little, but the idle screws were out somewhere around 4-5 turns out. Still rich.
I finally got around to hooking up a vacuum gauge and taking it for a drive. I'm not sure I did it right, but this is what I did: tee'd vacuum between back of intake and brake booster. Taped gauge to windshield and recording readings at different times. Had the mrs. with me to write things down so I didn't have to remember. Lol
This was done after the car was warmed up to proper temps.
*Warmed up idle before driving - 7 in hg
*55mph 2500 RPM (part throttle cruise) - 14 in hg
*WOT in 3rd - 4 in hg
*Decelerating from above it went up to 16 in hg
*2nd to 3rd WOT - 4 in hg
*Part throttle in 3rd 65mph 3200 RPM - just shy of 15 in hg
*2nd gear deceleration - jumped up to 17 in hg
*WOT from dead stop - 4 in hg
After driving for about 30 minutes:
*In neutral - 8 in hg (but was increasing)
*In gear - 5 in hg
*Idling in gear is about 850 RPM
*Idling in neutral is about 11-1200 RPM
So the main question is do I need to go back to 5.0 PV and try to adjust outboards leaner, try the 4.5 again and retune, or do I have other issues?
Sorry for such a long post.
I'm still trying to learn about carburaters. I know I'm overlooking something.
Hope you all can help me figure this out.
440 .030 over. Around 11:1 CR
MP 509 cam
6BBL
727 with reverse manual
Used to have horrible overheating problems. That seems to be taken care of. Had timing issues. Again, seems to be rectified now. Timing is around 16 initial and all in around 2200 RPMs at 34. I don't remember exactly what the timing is. It starts fairly easy when hot and no run on when turned off. I was having what sounded like spark knock at WOT. Now it feels like it runs out of gas during WOT run after going through the gears. It falls flat on its face above 3500 RPMs in 3rd. Does great from 1st to 2nd. Can feel it falling off when I shift into 3rd.
Outboard carbs metering plates drilled by ProMax years ago
Rebuilt couple times with new gaskets last year. Twice.
Trying to get the carbs set. Main jets are 65 I believe. Power valve is 4.0. I think I should go up to 4.5 or 5.0. I was at the 5.0 but idle was really rich. Burn your eyes rich. I could lean it out a little, but the idle screws were out somewhere around 4-5 turns out. Still rich.
I finally got around to hooking up a vacuum gauge and taking it for a drive. I'm not sure I did it right, but this is what I did: tee'd vacuum between back of intake and brake booster. Taped gauge to windshield and recording readings at different times. Had the mrs. with me to write things down so I didn't have to remember. Lol
This was done after the car was warmed up to proper temps.
*Warmed up idle before driving - 7 in hg
*55mph 2500 RPM (part throttle cruise) - 14 in hg
*WOT in 3rd - 4 in hg
*Decelerating from above it went up to 16 in hg
*2nd to 3rd WOT - 4 in hg
*Part throttle in 3rd 65mph 3200 RPM - just shy of 15 in hg
*2nd gear deceleration - jumped up to 17 in hg
*WOT from dead stop - 4 in hg
After driving for about 30 minutes:
*In neutral - 8 in hg (but was increasing)
*In gear - 5 in hg
*Idling in gear is about 850 RPM
*Idling in neutral is about 11-1200 RPM
So the main question is do I need to go back to 5.0 PV and try to adjust outboards leaner, try the 4.5 again and retune, or do I have other issues?
Sorry for such a long post.
I'm still trying to learn about carburaters. I know I'm overlooking something.
Hope you all can help me figure this out.