Just as the title says!
i am running at the moment 7 on leading and 11 on trailing seems to run well
car would not run with 7 leading and 9 trailing (stock) i would get mad sputtering and misfiring
at just around 9~10 psi
i am playing with the idea of running 10 11 combo , to see what that would do , comments?

 

I'm running 9's leading and trailing. I will get some breakup at 15 psi unless my plugs are pretty fresh...By the way, I have had good luck with Advanced Auto replacing my fouled plugs 2-3 times for free. NGK's have a warranty....this may be old news.

 

went for a ride (long) ride yesterday , running just 9 psi ,
dont want to up the boost yet since still have mad suspension issues
but i tried running 9 leading and 11 trailing , ...no breakups , and car feels nice
just got my bushings in , i still need the mazda pillowballs in the rear though
as soon as i get those installed and the suspension problem is solved (hopefully) i will be upping the boost
looking to run a comfortable 15~17 psi ...not looking for more
i made a dyno run making 405 whp @9psi , but with a A/F of under 10 (gauge doesnt go lower then 10 so ...how much lower is anyones guess )
so with better tuning it should yield some decent results

 

I'd be interested in knowing how the 11's workout with some miles on the plugs and higher boost. I've never had any breakup issues at 10 psi with my 9's.