If you had a fuel pump going south, would that cause the motor to lean out off the corner (low end), but not at the top end? I have been through the bypasses, barrel valve (19%), and the linkage but can't find anything wrong. Last night, the temp would climb fast on yellows but would drop just as quick when on the hammer. Three races in a row I have dealt with this and it even ran great in hot laps and qualifying, but started again in the heat and got worse in the main. It seems to get worse as the race goes on. My thought was that it couldn't make enough volume and pressure at low rpm but could at higher rpms. If not the pump, what else could it be? The Mag? I appreciate any advice you might have because it's got me stumped! I put a fresh pump in it today, but we all know it's tough to test before you get to the track! I run a West Coast 360 sprint out her in California.