What kind of angles are we talking about? Steep,tight,shallow!
What type of oil pattern,volume are we talking about? I know you only average 170-180 and may not know these answers but you can ask around and maybe find out,it will help us help you. I could recommend several different drillings for different angles that start off inside but may go out or stay tight depends on how you are playing the lanes. As a basic drill that I use for getting a steep inside angle with some dry boards to the right put the pin 6 inches over from pap above the fingers and put the cg/mass bias online towards the pap.This would be a 6"pin high x 0 degrees.I don't recommend it for you but as just an example of some of the creative ways to produce length with a huge backend recovery.
Give us/me the most info you can and thier will be people here to help.
Style of game you have?
Revs med,high,low
Where do some of the higher average bowlers play that have a similar style to you?
Ask the local pro shop guy for some advice and report back what he says,You never know what the pro shop guy will say but we will help confirm it if possible.
Where do you mostly bowl at? maybe some one on here bowls thier also and can help you out.
Good luck and let us know as much as possible.
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Here to fix something I know nothing about..