AlphaN blending

[dnb]

Has anyone used alphaN blending?  Is it worth the effort of making the hybrid tables?

I am suspicious of using alphaN for the whole of my map.  I don't know why, but it just doesn't feel "right". 
But there is so little resolution at low RPM/low load that pressure based tables don't really work.
(MAP at idle is 60 to 65 kPa)  When the engine is loaded, the MAP works nicely as you'd expect.

I'm a bit worried that with the blended tables I could run off the top edge of the map - 104kPa is equivilent 40% TPS, isn't it? - so should I compromise the resolution at high RPM (in the SD region) to get some more range in the low RPM (AlphaN region)?  Or is it a case of 40% throttle will raise the revs so fast that it'll be speed density no matter what?  (I suspect this isn't the case for a large capacity v8 with enormous amounts of torque from idle, provided I'm engaged in the activity of moving imovable objects from rest ;) ) 

Also, how do things like pressure based fuel cuts work with alphaN?  If I wanted to cut fuel at less than 20kPa, would that mean I cut fuel at 0% TPS, such that idle becomes rather troublesome? 

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I've had a play with the blending and decided that AlphaN was the prefered method with throttle bodied engines.

When I saw the way your engine moved around the load sites it looked so close to AlphaN behaviour as made no difference from what I could see.

Personally with big cams I'd be using AlphaN, in fact I think I'd use AlphaN on anything that wasn't turbocharged.

As for fuel cut, yes it will activate on TPS rather than MAP but its not really a problem because the RPM limits are changeable so it will start injecting fuel again when the RPM drops below the prescribed value.

I think you'll find that you'll get crisper response in an AlphaN setup.

[dnb]

My engine is still plenum based, although it does respond differently to most engines here due to the silly capacity. ;)

I've tweaked the map to use alphaN up to 2000 RPM or so, so I'll see how that goes.  I should now get away with not having 5 MAP bins of 5 kPa around the idle area...