I agree with both DAK and Don,
There's lot's of variables with getting the right settings on the leak down.
EX: if you buy a new hilborn stacks injection from Hilborn it will come preset at 26/28 PSI leak down and they recommend a 110 pill starting point. Everything want be right but it will be close.
Ron's, hilborn, and Enderle all have different barrel valves. I too start at 30PSI leak down and except for the enderle hat on a tunnel ram, i've had to come down to get good response. I have run as low as 18PSI with a 2 7/16" stacks injection with a PG 150-1 pump. Most people i know do not have EGT setups so they go by the temp of the motor.
I have 3 different setups, a bowl,stacks and blown and they all require different leakdown settings, but i think the leakdown setting has been pretty well explained.
I can remember running blown gas 40 yrs ago when no one had ever heard of a leakdown reading the hilborn barrel valve had a slot that looked like a screwdriver slot in the end of the barrel valve, you set that parallel and adjusted it until the throttle was crisp. Days gone by but still good in theory.
JMO
Zip.