Post #4 for the win!
Install a PV plug and go drive it. Watch the gauge, as you do some gentle roll-ons. Correlate the power-sag to the gauge. then
Install whatever it points to; as
@hunt2elk says probably up around 10.5 or more.
If you have been running a 7.5PV or less, you will find that now, with the right PV, ON THE STREET, you can probably reduce your MJ one size for everything but WOT.
To get the WOT fuel back just increase your secondary the one size.
If you were running a 6 number stagger, just try an 8 number.
When I installed the 10.5 in my 367, with the 223/230/110 Hughes cam, Drivability was much smoother and, had I had a 12.5, I would have tried it. As it was, the 10.5 felt pretty good so I left it
Going from memory, (this was in 2001), with the 10.5;
the P-jets went from 70>72, to 68>70, and it ran well on the 70s.
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When I installed a fresh above-the-hood air intake, and a 230/236/110 Hughes cam,(2004) the Primaries were lean at 68, not bad at 70, maybe a hair off at 72, and fat at 74 with an 8 number secondary stagger; so I ran it at 72P/78S for a long time, and eventually it settled at 74/80. But
On the street, I like to run a lil lean, 72/78>80 cuz it's snappier, and still revs happily to 7200.
The truth is that from 25/30 mph, to 65 mph, at WOT, is like less than 3 seconds, and my combo likes it a hair lean, (exploding in tire-smoke, fury, and a raucus roar that attracts cops like bees to flowers), so, she's not particularly fussy about the perfect jet-sizes, cuz the engine is not working hard at all..
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BTW, congratulations on selecting a sweet 9.5Scr/264 cam combo. In the 318, the Wallace calculator predicts a cylinder pressure of around 155psi@900ft elevation, which should still be able to run 87 gas; and it predicts a V/P of 120, which is pretty good for a cammed-up 318.
This V/P ratio, is over 8% better than than a stock lo-compression version; and only 10% sacrifice to a stock 9.0 engine; So you split it pretty good.
