Ok, if I am correct, the PM6 ECU is 88-91 Si/EX ECU, PG7 ECU is 86-87 Integra, and the PM7 is 88-89 Integra. OK so far? If not please correct me.

I have a 91 EX, SOHC ZC...I have the stock PM6 ECU in there right now, previously, on the D16A6 I had installed the PG7 and the engine promptly dropped 2 valve springs (and consequently, 2 rods) at high RPM. I don't think that the valve/rod problem was caused (directly) by the PG7...my lady thinks otherwise, I am not sure, so what harm, if any, can be done by using the PG7 ECU on the new engine? Please advise.

 

The integ ecu has a higher rev limit than the PM6... what rpm did the motor take a ****? Also, i've heard that it runs a little lean. Were there any signs of detonation?

 

Uhhh...he he he....the morning it let go, I was racing on the fwy, held between 6800-7250 rpm in 3rd for about 5-7 seconds (racing a T-Bird SC), a few minutes after that it started knocking bad and kept getting worse and worse...I live 30 miles from work so I didn't have much choice other than to keep driving to see what was gonna happen...got to work ok...that afternoon, trying to drive home it ate 2 rods (I think, never had the block stripped down) or poked SOMETHING through the block cause about 5 minutes after I started it again (driving home at fwy speeds) it took a huge ****, one last big knock and it died...I let it coast down, stopped the car and popped the hood...oil cap was nowhere to be found(!), and behind the car, about 400-500 yards long, a trail of coolant on one side of the block (approx near the #4 cyl), and a trail of oil on the other side (near the #1 cyl)...it was some pretty crazy ****. At least I won the race.

 

probably just a ten year old motor that finally gave out...