LH map with verticle banding
08-17-2019, 03:38 PM
#1
LH map with verticle banding
I remember seeing a discussion on this but have searched and can't find it. At any rate, did a tuning run this morning accelerating as little and slow as possible. As you can see I am getting vertical lean bands. The worst ar at 2400, 3000 and 3200. Any suggestions. on how to clean these up. This is open loop.
Thanks in advance, Ralph
08-17-2019, 03:51 PM
#2
Rennlist Member
I remember seeing a discussion on this but have searched and can't find it. At any rate, did a tuning run this morning accelerating as little and slow as possible. As you can see I am getting vertical lean bands. The worst ar at 2400, 3000 and 3200. Any suggestions. on how to clean these up. This is open loop.
Thanks in advance, Ralph
Irrespective of that there is nothing much you can do about those resonance bands other than richen the cells they occur in a bit and then of course all other points in that cell rpm range end up richer as well. The problem transcends a number of load point cells as it happens at specific rpm points. Whether or not the problem could be modulated with a different damper setup I do not know but it is an inherent characteristic of the stock fuel.
delivery system.
The only way I could fathom out as to how this issue could be addressed would be to modify the rpm bands so that the resonance could be isolated and tuned discretely. I dare say that is something that someone like Ken [Porken] could do but then sharktuner would not function or recognise it without modified coding I suspect.
08-17-2019, 04:07 PM
#4
Rennlist Member
That is pretty much what happens but not sure I understand why you would be too concerned given those operating points are with the motor lightly loaded and thus not of much relevance or so I would think.
Appreciate you have a blower but the MAF reading is not aware of that. As I recall the problem is less obvious at higher load values but then we generally run richer at such operating points so it looks less obvious.
Appreciate you have a blower but the MAF reading is not aware of that. As I recall the problem is less obvious at higher load values but then we generally run richer at such operating points so it looks less obvious.
08-17-2019, 06:35 PM
#6
[QUOTE=FredR;16045244]That is pretty much what happens but not sure I understand why you would be too concerned given those operating points are with the motor lightly loaded and thus not of much relevance or so I would think.
Fred,
I think it is a combination of paranoia, ignorance, curiosity and a propensity to "chase ghosts". It really helps having expert like you keeping me on track.
Thanks
Fred,
I think it is a combination of paranoia, ignorance, curiosity and a propensity to "chase ghosts". It really helps having expert like you keeping me on track.
Thanks
08-17-2019, 06:52 PM
#7
The FPR is a couple of years old. The dampers are probably original. I checked them out and they seem to be working correctly and not leaking. However, I did notice that when I pull the vacuum hose off the fuel pressure gauge mounted on the rail vibrates less. They are 31 years old so that could be the problem.
The injectors are 30 lb and were recently rebuilt by Witch Hunter.
Thanks
The injectors are 30 lb and were recently rebuilt by Witch Hunter.
Thanks