Hi all,
having a curious issue with load spikes at WOT.. I've attached my tune, a logfile and a screenshot of the load spikes/ripple I'm talking about. Basically I can be at WOT and in the 4500rpm onward range suddenly have a massive lean misfire (never fun) which baffled me for a while. Take a look at TPS, MAP and LOAD.
However I've noticed a couple of things - first is my barometric pressure seems to be zeroing out 93kpa - this logfile was taken at Phillip Island racetrack - it was more like 103kpa according to weather report for the day. I have a feeling this baro error added to the ITB switchpoint set at 92kpa, and the almost imperceptible ripple/noise on the MAP waveform in sync with the strange load fluctuations is the root of my problem - but I thought I'd run it past you all to see what you thought..
In playback of the log - you can see that load fluctuation dropping VE / Ignition down in to the bottom third of the table - causing the lean events.
MS3 + MS3X with mapdaddy dual sensor, knock sensor and rtc modules.
Appreciate all help and criticism as always.
Cheers,
Scott.
MS3 ITB mode load spikes
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Re: MS3 ITB mode load spikes
Is your "TPS switchpoint" curve set correctly? If it is then your throttles are massively oversized.
Your datalog doesn't include Baro, so I can't asses what is going on .
James
Your datalog doesn't include Baro, so I can't asses what is going on .
James
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New users, please read the "Forum Help Page".
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Re: MS3 ITB mode load spikes
Thanks James - I'll take another log incorporating baro and upload. What a duffer !
Yes, they're 38mm throttles with open stacks feeding stock intake ports and cams on a 2L Alfa TS. They are well oversized for the current engine build.... the engine under construction will breathe a little better though...
Cheers,
Scott.
Yes, they're 38mm throttles with open stacks feeding stock intake ports and cams on a 2L Alfa TS. They are well oversized for the current engine build.... the engine under construction will breathe a little better though...
Cheers,
Scott.