Once known as Hartley18
Join Date: Aug 2007
Location: Melbourne, Australia
Thanked 85 Times in 85 Posts
Rep Power: 11
Your set-up, whilst not "ideal", doesn't seem too bad to me.
The ideal angle for a boom vang is 45 degrees, but on many boats this isn't practical for many different reasons so you get what you get.
If you can move the attachment to, say, 25% of boom length that would give you better control, but increasing purchase might have the same result.
Can you post a pic of your set-up??
A bad day on a boat beats a good day in the office