carb:
* Primary T-slot .030-.040"
* Secondary blades 1/2 turn from seated (about .010" T-slot open)
* 830 HP main body w/downleg boosters, IAB reduced from .073" to .067"
* 830HP metering blocks (IFR reduced from .040" to .036"). I also do have a set of stock 4781-3 blocks that I play around with...seems to help a little, but not much.
* Quickfuel 1-3/4 blade 850cfm base plate (recently bought, neither a help or a hurt). I have drilled the bypass holes in blades to 0.172" to keep car idling and maintain T-slot position. The stock Holley base plate holes were .150".
* 82 / 86 main jets
* 2.5" PV front, rear blocked...vacuum at idle is around 6-7" in neutral, 5" in gear.
* Mixture screws have been all over, car seems to like them between 1-1/4 and 1-1/2 turns. Given the situation, I run them at 1-1/2.
combo:
* 428 + .060 Pontiac (4.181 bore x 4 stroke)
* 325cfm (200cc) @ .700" aluminum heads
* 11.25 to 1 CR
* 264/268 @ .050", 296/300 @ adv, 108 separation, installed at 104, .620/.629" gross lift, flat tappet
* victor intake, stock
* 3600rpm stall
* T350, 12-bolt w/3.90 gears, 28" tire.
The problem is that when I approach 2000rpm & cruise @ 40-45mph, the engine will (at least i think) go lean and start to misfire. typically, it will also start to raise the water temp. it idles perfect. WOT seems to be good too. I've tried adjusting the idle mix screw from 1 turn all the way to 2 turns. no effect at all and the car won't stay idling.
i recently checked the float levels, and they are right at the bottom of the sight plug. it seems the general feeling is that the booster isn't pulling enough fuel during the 2000-3000rpm range. maybe it's the victor? i'm going to run the float a touch higher, maybe that will help.
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