map vs alpha n?

[Seight-v8]

hello all,

just been reading a fairly new rover v8 tuning book......and the section on ECU tuning, says that non turbo cars, with map readings under 65kpa, and large overlap cams, would be better on ALPHA N (TPS) maps instead of speed density maps......

So if this is true?, then mine would meet all of these requirements......but ive never used anything other than SD map based.....

i don't want to start down a road that makes it worse and has other side effects......

So thought i would ask.

thanks
scott