Also I think you are using the M90 compressor. The lightnings are using the M112, right? I would assume the M90 would generate alot more heat than the M112 at the same boost lvl. The 90 has 20% less displacement. It might be that when you increased the boost you REALLY increased the charge temp. I would go back to a 9# and get the charge cooling fixes implemented. Then try the 12# after you have those worked out. And by all means get on the Dyno to get some a/f numbers.
Jes

 

How about opening up the hood with a scoop to help disipate the heat?

 

oh man! you and Ray keep reading my mind!

I though about getting one of Neals scoops or the louvers that Flatsman did or a Cold-fast air kit like the Lightnings use and that 00expo modified. I also looked for a hood like the one made for the pre-97' F-150s that have a working ram air hood that feeds the engine. I guess I would try what is the cheapest and gets rid of engine heat the most

 

Rocketir - Iron Horse also has a 4.6, so he has about 20% less displacement than an L as well.

Ian