Man what a thread. I love it.
To start off, I agree with those saying the tecno circuit isn't a screamer. Cause it just plain isn't. I've had it on a handful of kits and it kinda does the budget circuit pipe thing. AKA bangin mid range and topping out early. I feel like I could only get 9250 max rpm outta a tecno circuit on a good day. Like 9k is really all they're gonna put out in my experience. Should def spin further than 8k but man that last 1000 rpms is gonna be after the pipe has ran out of steam. With that being said, tecno circuit is the fuckin shit. I fux with it way harder than the proma. It seems ever so slightly built better and if my memory serves me right.. you can drain the tranny without fuckin with the pipe.
Secondly, that 2.5mm that you lifted the cylinder to clear the exh port has completely altered your exhaust port timing. I dunno what some of yall think about 2.5mm on the exhaust port but in my world that's a pretty significant exhaust port timing change. Like you can lift a cylinder maybe 1mm without fuckin with the OG timings too much BUT man after you go past that you've created an entirely new tuning scenario when compared to the OG timings if the piston magically cleared exh port at bdc. If I were you I'd break out the degree wheel and get a concise number for what my exhaust port duration is in degrees. With that number you can further assess how much you've moved the powerband upward. Circuit pipe with gnarly exhaust port timing is a weird tuning combo. It's like the pipe wants to hit low but the cylinder wants to revvvvvv. Some people swear by it though. OG riggsby is a huge advocate of AJH with circuit pipes. Which makes zero sense to me but fuck.. he's the man when it comes to AJH.
Third, 1.8mm is a lot in my book. Yes you already know that but I still had to say it. My piece of shit peugeot has a squish of 1.6mm and I was giving it the stink eye heavily when I was building it. I'm not too big on kstar for this exact reason. In my experience it's always needed hella base spacing ( like the 2.5mm you did ) and then a whole 'nother shitshow to get the proper squish. I'm not knowledgeable enough to know the exact tuning effects of a big ol honkin Texas squish band but regardless I'd work on gettin it down.
Fourth, AJH is an entirely different rabbit hole. That shit is some guru e50 screamer tech. I'm sure you've read the threads but man after you get the proper piston for it... that bitch needs a deeeeeeeep countersunk head. Once again, riggsby is the guy to talk to. He has multiple heads countersunk differently for that AJH life.
Ok. I'm almost done.
If I had to go a certain direction on this i would tackle your base spacing / squish issue. 9/10 people don't base space their kstar and they run well. Yes they never clear exh port but.. I guess thats how it goes down sometimes.
You got this! Keep fightin the good fight. And as guru once said ( rest in peace ) - " breathe, study lessons and build your inner power "
XOXO - jon