Bottom or Top End needle first ?
11-10-2006, 07:04 AM
#1
Bottom or Top End needle first ?
I'm a little confused at the moment. Some websites, as well as some pros have suggested when it comes to engine tuning, do the top end first, follow by the bottom end. However, lately, some friends I made at turf and farmway suggest otherwise - tune the low end , and then the top end.
Now, I am pretty confused. I do have to agree that with an ultra rich lowend, tuning the top end will be difficult as the engine may bog severely, resulting in a too lean setting on the top end.
Currently, what I do is to get the bottom end to be closer to the appropriate setting, then do the top end, and then come back to the bottom to fine tune.
On a side note, what does this mean at idle , after coming in for a pit stop ? Idle drops low , then rises alittle for 3 seconds, and then come back down to a low constant idle again. Rich or lean ?
Now, I am pretty confused. I do have to agree that with an ultra rich lowend, tuning the top end will be difficult as the engine may bog severely, resulting in a too lean setting on the top end.
Currently, what I do is to get the bottom end to be closer to the appropriate setting, then do the top end, and then come back to the bottom to fine tune.
On a side note, what does this mean at idle , after coming in for a pit stop ? Idle drops low , then rises alittle for 3 seconds, and then come back down to a low constant idle again. Rich or lean ?
11-10-2006, 10:16 AM
#2
Originally Posted by nikkor
I'm a little confused at the moment. Some websites, as well as some pros have suggested when it comes to engine tuning, do the top end first, follow by the bottom end. However, lately, some friends I made at turf and farmway suggest otherwise - tune the low end , and then the top end.
Now, I am pretty confused. I do have to agree that with an ultra rich lowend, tuning the top end will be difficult as the engine may bog severely, resulting in a too lean setting on the top end.
Currently, what I do is to get the bottom end to be closer to the appropriate setting, then do the top end, and then come back to the bottom to fine tune.
On a side note, what does this mean at idle , after coming in for a pit stop ? Idle drops low , then rises alittle for 3 seconds, and then come back down to a low constant idle again. Rich or lean ?
Now, I am pretty confused. I do have to agree that with an ultra rich lowend, tuning the top end will be difficult as the engine may bog severely, resulting in a too lean setting on the top end.
Currently, what I do is to get the bottom end to be closer to the appropriate setting, then do the top end, and then come back to the bottom to fine tune.
On a side note, what does this mean at idle , after coming in for a pit stop ? Idle drops low , then rises alittle for 3 seconds, and then come back down to a low constant idle again. Rich or lean ?
For me, I'll first rich out low end a little (but not rich until bogging), then start running and tune the high end, then the low end.
Idle rises a little for 3 seconds to me is not a issue.......sometimes it's the pipe, fuel tank, back pressure tubing length, air bubble in the fuel line etc........
As long it can idle at a low rpm and wouldn't die off it's ok to me........hahaha
Just my 2 cents
Last edited by Nipple; 11-10-2006 at 10:27 AM.
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
