So... this is mostly for xctasy but I would be interested in any thoughts...
My CFI 5.0 is now running really really well, but that has exposed the limits of the CFI and I am having some fun trying to squeeze the last bits out of it.
I have been tweaking the ignition system and the fuel pressure and have come to the conclusion that the poor thing is just running too lean pretty much across the whole sweep of the rpm range. Not dangerously lean but it wants more fuel. I started thinking about larger injectors but I have been finding stuff that makes me think that the fuel pressure could go higher.
Injectors and Fuel Supply (megamanual.com)
Assuming that I 'can' make about 230hp flywheel with my setup (probably much higher but not with CFI bore diameter), I should be pushing 60 psi into the injectors. Xctasy, do you think this is sane? Currently (well, today at least) I was pushing 44, which was doing better than 42. I drove 80 miles at 70mph today at 44psi and the engine was running warmer (before the engine was running a very cold 182ish, so that is a good thing) and the oil was behaving better as well (temp and recovery of pressure after highway speeds). That makes me think it wants more (I am assuming strange localized hot spots due to lean condition). The little lean miss was still there, but barely, at idle.
Watching the air fuel ratio while cruising, it is starting to spend pretty much equal time below 14.7 as above when cruising but still a little on the lean side. 16 mpg mixed driving with a very very very heavy foot. When it gets into a funk and drops to 13.5 at idle, it idles perfectly.
I am going to go for it this weekend when the temperatures come up a bit but any thoughts would be appreciated.
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