Well, drove the truck some this last week, getting around 10.25 mpg. Slight improvement over the 9 I was averaging a few months ago.
I kinda 'fixed' the throttle return issue by using a much heavier return spring which seemed to help. It idles down quicker now when you close the throttle and does not seem to get stuck in a high idle position though it takes more foot pressure to accelerate. I believe I need to really dial in the fast idle cam on the electric choke, it might be on the wrong step or some such thing. If I see something there that can be changed and it works maybe I can go back to a lighter spring. The choke works but I am considering ditching it for the warmer months.
Messed with the idle screws a bit, the idle is pretty good right now, generally around stoich. It idles at 1,000 rpm but what can you do, it's got a big cam with a lot of overlap and a good amount of initial timing at 18.
While driving, the A/F swings are not as big as before, it goes to low 12s-high 11s at WOT and about 16 when the secondaries open then it goes back to 12-13. Cruise was about 1/2 point higher all around, mostly above 13.5 depending on road speed/rpm.
Was thinking a jet change would be a good place to see if I could lean out the cruise, has # 70s in it now. I gave my buddy my only pair of 68 jets a while ago which I think would have been good for this situation, thought 67 might be a little too small and 69 wouldn't do anything. Still have yet to hook up a vacuum gauge, maybe I will do that this weekend. Might try a lighter spring in the secondary as well to see if the accel is a little more snappy.
I have to say that the aero thing is relevant here. The couple times I drove the truck it was really windy, like 40+ mph gusts. When driving out on a more open stretch of road with heavy crosswinds I could feel the truck struggling. Really thinking about a front spoiler.
Just chipping away at it a little at a time. Hope to get to the cam and intake swap soon now that it's warming up.
