What is the advantage of using 16% fuel over 20%? If I wanted to switch to 16%, what do I need to do? I have a .12 SH non-turbo with O.S #6 plug.

I found out that 16% is used for international racing where they limit nitro percentage.

you get more runtime out of a tank of fuel

What do I have to do to my engine to run 16%?, add or remove shims.

Simply use the original shim (installed) from factory.

16% - less shim or original shim

20% - more shims

Thanks, now days it seems as if you have to wait a week for a response.

Nobody HAS to give you a response. You're welcome, some of us have other things to do...

If you would have done a "SEARCH" for your question you would have found your answer about a dozen times. Nothing wrong with asking questions; but you should do a search first. You never know what you may find. Some of the seasoned guys don't like answering questions that have been asked 20 times before.


Pass you soon...