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I have an imported car that was built in Japan and would love some other opinions on this timing map. When I saw the map I was pretty shocked, but I might be wrong and it be a perfectly fine way of tuning timing. Just to preface this, this car wasn’t built recently it is a time capsule and has remained virtually unchanged since the early 2000s up into my ownership. Some hard track time, and the compression test was perfectly fine. It has an old HKS kit on it and was set to ~12psi when I got it, which was the ragged edge of duty cycles. First picture leading, second picture show split taken from Xavier’s FC-Tweak.
My brain says throw the tune out and start over, but it’s hard to ignore the fact this car has lived as well as it has on it.
Note: the PIM column is the same values as standard power fc with factory oem map sensor
Last edited by williamdb13; Apr 24, 2024 at 08:43 PM.
So scaled to a 2 bar map sensor (up to 14.5psi boost) that looks normal to me at 1st glance
Do you have any questions about specific areas of the maps?
Main map-
Lower idle timing than stock for smooth idle on a ported motor
Aggressive advance in vacuum for quick throttle response.
Trailing map-
low split/negative split in areas where turbo is generally just spooling (for increased egts to aid spool.) Looks like its sequential turbo still as the negative split isnt there at transition?
No split at idle for smoother idle on ported engine.
So scaled to a 2 bar map sensor (up to 14.5psi boost) that looks normal to me at 1st glance
Do you have any questions about specific areas of the maps?
Main map-
Lower idle timing than stock for smooth idle on a ported motor
Aggressive advance in vacuum for quick throttle response.
Trailing map-
low split/negative split in areas where turbo is generally just spooling (for increased egts to aid spool.) Looks like its sequential turbo still as the negative split isnt there at transition?
No split at idle for smoother idle on ported engine.
I guess my question is really related to when it’s under boost the leading timing being “low”, and then using the trailing split to essentially advance the timing. I thought that this was considered something not to do? Maybe that’s just a preconceived idea on my part. Thanks for sharing knowledge to all that are responding.
So scaled to a 2 bar map sensor (up to 14.5psi boost) that looks normal to me at 1st glance
Do you have any questions about specific areas of the maps?
Main map-
Lower idle timing than stock for smooth idle on a ported motor
Aggressive advance in vacuum for quick throttle response.
Trailing map-
low split/negative split in areas where turbo is generally just spooling (for increased egts to aid spool.) Looks like its sequential turbo still as the negative split isnt there at transition?
No split at idle for smoother idle on ported engine.
I just saw your comment about the turbo setup no this is a HKS t04r I believe on a s5 motor, with FD3S upper intake manifold and an AP engineering power fc. Thanks
IGL looks normal for me.
But split is frigged up like many early ones where because the newbie tuners either did not know about how to adjust it correctly or just ignored it.
It is soooooooooo inconsistent!