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Im trying to find a stock timing map for an RB25DET for the purposes of comparing it to my adaptronic setup, mainly in the partial throttle region. The base maps that come from adaptronic are even more conservative with timing (for safety, liability etc), and aren't a good comparison.

That would be the first step. Secondly does anyone know how to convert a AFM based load map to a MAP sensor load map?

Im trying to find a stock timing map for an RB25DET for the purposes of comparing it to my adaptronic setup, mainly in the partial throttle region. The base maps that come from adaptronic are even more conservative with timing (for safety, liability etc), and aren't a good comparison.

That would be the first step. Secondly does anyone know how to convert a AFM based load map to a MAP sensor load map?

The Nistune Neo maps would be the easiest ones to access....even if they are probably a little different to the earlier 25s. There may be some normal 25 maps lying around on the net from the EEPROM burning days. Toshi would certainly have some.

As to "how to convert"....that's not really possible without making some measurements. There is a non-linear relationship between MAP signal and AFM signal on any car. The other problem is that the TP load axis on Nissan ECUs is not just a measure of AFM signal either - it's the output of a formula that already takes RPM into consideration so that the same AFM signal will give different load (TP) values at different RPM.

The measurements that you could make to help out would be to log RPM, MAP, TP and timing at the same time so you can kind of fake up a MAP based timing map by pulling (RPM, MAP, timing) values out of the data logs in parts of the log where you know you were driving normally (ie under load, so running the maps normally, not overrun, throttle closed stuff). You could compare those against the TP recorded at the same time to make sure that what was logged was similar/same as what is in the original AFM based timing map.

Naturally, all of this would need to be done on a Neo with Nistune, or possibly on an old 25 with PowerFC with base maps.

I believe this is what you're looking for, I created this map using a mixture of Haltech's base map and the factory RB25DET map from Nistune

post-22311-0-96554800-1424148166_thumb.png

Also here's a Haltech base map

post-22311-0-63941400-1424148336_thumb.jpg

Thanks, it looks like my map is retarded in the cruising area. I guess I have your ecu file off the adaptronic forums. If that closely matches stock, Ill copy the low load cells. Actually my map is quite similar in other areas of the map, good to know that the tune is "relaxed" on full boost.

The Nistune Neo maps would be the easiest ones to access....even if they are probably a little different to the earlier 25s. There may be some normal 25 maps lying around on the net from the EEPROM burning days. Toshi would certainly have some.

As to "how to convert"....that's not really possible without making some measurements. There is a non-linear relationship between MAP signal and AFM signal on any car. The other problem is that the TP load axis on Nissan ECUs is not just a measure of AFM signal either - it's the output of a formula that already takes RPM into consideration so that the same AFM signal will give different load (TP) values at different RPM.

The measurements that you could make to help out would be to log RPM, MAP, TP and timing at the same time so you can kind of fake up a MAP based timing map by pulling (RPM, MAP, timing) values out of the data logs in parts of the log where you know you were driving normally (ie under load, so running the maps normally, not overrun, throttle closed stuff). You could compare those against the TP recorded at the same time to make sure that what was logged was similar/same as what is in the original AFM based timing map.

Naturally, all of this would need to be done on a Neo with Nistune, or possibly on an old 25 with PowerFC with base maps.

Thanks, I guess the old fashioned way will have to do, ie 2 person road tune. One screen watching WARI, the other watching consult, tweak timing to suit.

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