- Wed Feb 07, 2024 7:58 am
#67063
This is the same process the factories have used for many decades, even back to old points distributor days with vacuum advance. That's what the vacuum advance was for - to add that extra timing required for efficient and safe part-throttle lean cruise.
The process to find stable lean cruise is quick if you can find a way to do the block of VE value changes on-the-fly while you drive. Perhaps a tuning buddy to drive while you handle tuning? If not, I've done it alone like many others, and finding the cruise AFRs and timing from 30 to 110 kph should take less than an hour if flying solo.
Rednaxs60 wrote: ↑Wed Feb 07, 2024 4:04 amThe AFRs you mention are quite lean, wouldn't have thought I should lean out that much.You are "trying" AFRs. We avoid that. We find AFRs, and I think you'll be amazed how lean they can go efficiently. So, I understand it's tough to monitor and change VE values while cruising alone, but otherwise you'll need to ride, log stable cruise at a specific load & rpm of perhaps 60 kph, then stop, review and change the block of VEs on the side of the road and repeat to find the leanest stable cruise (just rich of lean surge). Once found, enter the AFR that resulted in the table, and move immediately to tuning the ignition at that same AFR block area for minimum MAP. Then that area is tuned for maximum efficiency.
This is the same process the factories have used for many decades, even back to old points distributor days with vacuum advance. That's what the vacuum advance was for - to add that extra timing required for efficient and safe part-throttle lean cruise.
The process to find stable lean cruise is quick if you can find a way to do the block of VE value changes on-the-fly while you drive. Perhaps a tuning buddy to drive while you handle tuning? If not, I've done it alone like many others, and finding the cruise AFRs and timing from 30 to 110 kph should take less than an hour if flying solo.
-= If it was easy, everyone would do it =-