[Dave in MN]

I have installed a couple on customer's cars and if set/timed correctly, they work quite well. I have also replaced the main bearings on four engines that either the owner or someone else installed the kit where they had not set the timing correctly. If you install one, I suggest you use a timing light to verify the resulting timing at 2200 rpm. Check it twice and then listen carefully for any knocking.
28 degrees max for a standard compression head and less advance for higher compression heads.

On one installation, I needed to enlarge the hole for the lower distributor shaft in the copper head gasket. The lower shaft was rubbing on the gasket and would not respond correctly to changes in rpm. I used a tapered drift punch to open it up with hand pressure.
Good Day!