9.4---9.7= 30 hp gain? That's hard to believe.

https://www.rx7club.com/showpost.php...&postcount=121

"9.2 comp. rotor ran 13.2 et @ 106 mph. 9.7 comp rotor ran 13.2 et. @ 112 mph. so who ever said 9.7 is only worth 2-4 hp is full of it. ( I don't remember who or which thread.) I figure it gained about 10-15hp at the fly wheel at least."

oops you're right. but keep in mind the 9.7 motor did 231hp before the dyno stopped reading @9600rpm

on a stock port engine i'd expect less than 5hp difference at the top

"on a stock port engine i'd expect less than 5hp difference at the top"

Yeah, that sounds about right, if that.

why do people spend $1200 on the master kits?

...

Because they want to know they replaced every part they could? I dunno...