No wonder DV's new carb book doesn't delve into emulsion. There is still a total misunderstanding of the PV to conquer first!
GARY C wrote:No wonder DV's new carb book doesn't delve into emulsion. There is still a total misunderstanding of the PV to conquer first!
See you have the option of writing a book, answering the OP's question or making a smart ass comment...some don't have that option.
lluciano77 wrote:I have a wideband 02 sensor, a vacuum gauge in the dash, and a tach. I know exactly where my engine goes lean....1800 to 2500 RPM. This happens in drive (3rd) with light to moderate accel. My fuel curve is right on the money everywhere else. At the above cruise RPM I am usually around 16" of vacuum. Distributor curve is good as well at 20 initial, 34 total, and basically all in at 3,000 RPM. With a 3 step dist. curve. I have vacuum advance set at 5" via manifold vacuum and all in by ilde vacuum (12"). My torque converter is a 2,500 stall.
My carb is a Demon Annular 830. I am using the lower IFR locations. Metering blocks are at Holley 4 hole spec. Primaries are at .020" showing and square below the blades. I am running a 6.5 PV. Jetting and PVCR area is good all around. At least under full throttle launches.
On the wideband 02 the fuel curve doesn't richen up when the above problem happens. It stays roughly at 14.5:1, untill I pass this range or dowshift and then goes to a more healthy 12.5 under heavier load.
My IFRs are possibly smaller than they should be. I know last time I messed with the carb I brought them down, and enlarged the IABs to get my idle right. I don't have all the sizes...will have to measure this weekend. But I am guessing the IFRs could be at .028"
So with the above known. I was thinking of running a 10.5" PV. But I don't want to waste gas in other conditions. Where is the most likely place to cover this gap? Larger IFRs? The 10.5 PV? Or could this be an MAB problem not bringing my main circuit in in time?