I did a search and couldn't find the thread on breaking in the Norvell.
I tried to run my Norvell on a modified Baby Flight Steak with a modified Perfect tank converted to uniflow and it would not hold a needle setting.  I assumed the engine was already broke in but could be wrong.
I was using 10l29 at first but then switched to 25% Sig fuel, not sure of the old content.
 I have some Norvell fuel but forgot to bring it with me.
How much fuel to get it to break in and run?

Jay

Too much nitro, unless you add a lot of head gaskets. I run 7% nitro, 11% castor, 11% synthetic. 5.5 x 2.5 APC prop. Unlike Cox engines, these will overheat and run badly if at all over propped, over nitroed or over compressed. Let the engine sing a 19k note on the ground minimum. 

If you want the extra power that Nitro yields, you must add extra gaskets.

A little late, as I missed this thread, but here's a recent writeup I did on breaking in a Norvel. I opt for the old methods learned from the combat guys rather than new the quick and easy method from NV Engines.
http://stunthanger.com/smf/index.php?topic=32566.msg324763#msg324763