Compression

I wonder if some of you guys mighta dropped the ball on this one.
How many 9.5 engines can you actually jump to 11.5
"with no other changes"?
I know OP didn't say, but if an SBM,
11.5 has the potential to quickly run the pressure up near to 200 psi;
Which I have run BTW, and it was fantastic!
Ima thinking 33IMP/ post #6, hit pretty close to home.
Ima thinking the 9.5 engine would have, had to have been, a less than exciting build to start with.
Since you said this , I'll say this, that's the reason I didn't reply & no details and a anemic start.