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Hi All,

I have a Type 4 nistune on my ER34 GTT.

I am wondering why on the timing map the rpm scale skips 2,800rpm? It goes straight from 2000, 2400, 3200, 3600.

But the fuel map doesnt, it goes 2000, 2400, 2800, 3200, 3600 as you would expect.

Second question what does say 2000rpm mean. Is it from that value up to the next value such as 2000-2399rpm? or is it centred around 2000rpm so 1800-2200rpm?

Cant find that info in any of the nistune documents. Any help much appreciated!

the ecu interpolates so every cells affects the 3-8 cells around it aswell. ignoring load, if you have a cell at 2000rpm and your doing exactly 2000rpm it'll take all its values from that cell, if your next cell is at 2400 and your doing 2200 it'll take half from each. likewise if your doing 2100, it'll take 3/4 of the 2000rpm cell and 1/4 of the 2400rpm cell.

no idea why the map skips 2800, does it have an extra cell up top instead?

Hi All,

I have a Type 4 nistune on my ER34 GTT.

I am wondering why on the timing map the rpm scale skips 2,800rpm? It goes straight from 2000, 2400, 3200, 3600.

But the fuel map doesnt, it goes 2000, 2400, 2800, 3200, 3600 as you would expect.

Second question what does say 2000rpm mean. Is it from that value up to the next value such as 2000-2399rpm? or is it centred around 2000rpm so 1800-2200rpm?

Cant find that info in any of the nistune documents. Any help much appreciated!

the scales are 100% configurable, you manipulate the fuel and ign RPM scales to suit the engine characteristics.. you only have a fixed total amount of axis points so you move them around to suit.

scaler is Fuel RPM scaler under scaler tab.

DO NOT ADJUST THESE... copious amount of time setting the scalers and maps to produce the smoothest power delivery in your tune file.

the scales are 100% configurable, you manipulate the fuel and ign RPM scales to suit the engine characteristics.. you only have a fixed total amount of axis points so you move them around to suit.

scaler is Fuel RPM scaler under scaler tab.

DO NOT ADJUST THESE... copious amount of time setting the scalers and maps to produce the smoothest power delivery in your tune file.

Thanks Trent, I was just curious. Definitely not changing anything till I run it by you.

Only thing I have been considering is dropping the timing increase around 3200rpm. My tyres could hold the boost hit on 98 but the fact on E85 (with the extra 6 degrees of timing at 3200rpm) builds an extra 3 psi and has a torque peak and then drops off and then increases again. I was thinking if timing, therefore boost and torque drops back to similar numbers as on 98 fuel then it would be a smoother torque increase. This would provide a better chance of my tyres holding on.

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