ok, i have discussed my personal experiences with both ecu's and i'll try to be as fair as i can once again.
the p30 is the BEST ecu for a stock/close to stock b16a. the fuel curves and timing are excellent in making the best power for this setup, and remember, a b16a from honda runs perfectly, so why fix what isn't broken.
ok, with that said, chipped p28's almost always have programs that are designed to run with 1.8's. so basically, its like running a p72 (gsr ecu) with your b16a. the timing is not correct...which is going to cause a loss in hp. second, these ecu's are usually designed for mugen/jun/spoon motors which are higher compression. this means they burn more fuel, which your stock b16a just isn't capable of doing because of its lower compression and smaller displacement.
and hondata p28's are used becasue they are most common, the fact of the matter is any vtec ecu can be used, it just so happens that p28's are the least expensive.
I'm ordering it today or tomorrow, and it will be going onto a p28.
And I don't consider hondata a chip. not in the least.
like chet said, the programs that are available are just crappy unless you HAVE a skunk2-spec'ed motor, or a JUN'ed spec motor. Again, like chet said.
the p30 has an ideal fuel curve. even with a vafc, unless you dyno tune it out (if you consider a vafc a "tuning" device, cuz i don't), you are better off with a stock p30 and a vafc to make MINOR adjustments.
well i'm running a stock p30 and i'm not happy with it at all, my rev limiter is about 7800rpm, on top of that I have a speed limiter at 140 , that really bothers me when i'm goin up to the track. I'm not even getting all of the power my motor can give. I am most likely trading for a skunk2 chipped P28 what do you think?
I dont know, I'm not really proud to say it (because I would have rather done it myself) but I bought my car the way it is so I really couldn't tell you, my tach may be off I guess but my vtec xover is at 5k and i hit rev limiter somewhere around 7800, I cant see exactly but my tach wont even hit 8k.