Look and read my post carefully before jumping the gun SIR.
1st, I didn't say "Map ECU" for shits and giggles... thats a piggy back system and not just a fancy name.
2nd, All Supras are NOT MAP based SIR, only the JDM ones are (do your research).
3rd, Even around 500hp~(which is chump change for the 2JZ) you're going to want to upgrade to some form of piggy back if not a stand alone altogether. E-manage is ten thousand years old in terms of technology and preference, AEM is the weapon of choice for all the big number Supras out there.
4th, This is where you are correct, that was a repeated typo on my part, I dont know what I was thinking when I posted this comment. The thicker head gasket yields a lower compression which is what you want on a forced induction car. Anyone can conclude that installing a thicker head gasket leads to lower compression.
5th, If he's ever going to go turbo on this car, which is VERY unlikely, a check engine light is going to be the least of his worries.
6th, MKIII Supras ARE infact MAF based and I've turbo charged aswell as modified several 7Ms using a MAF, I am aware of its limitations.
7th, There is NO SUCH thing as a USDM 1JZ (wow), that engine NEVER came to the United States in ANY car PERIOD so it would stand to reason that it never CAME with MAF.
8th, Converting a car from MAF to MAP is a simple matter of installing a "Map ECU", so people that change their "complete wiring harnesses" are retarded morons.
9th, I personally dont like Hondas, I've always preferred Toyotas. I dont know and care to know the compression of a general Honda, but if it IS higher, then you're going to have to find ways to lower it whether it be via a thicker headgasket or a lower compression pistons.