Best Fuel Pump Advice for Newb...

Mattax said
It's possible the pumps have enough difference in the return spring the fuel level is now a little lower. Even so, that usually a fine trimming - nothing near a full AFR ratio - and would impact low throttle the same or maybe even more. Maybe something to do with whatever was wrong with the old pump. All speculation anyway.

Now that you mention it, it did seem a skosh leaner just cruising around, but not nearly 1 full point. But an interesting bit of info there.

Mattax said
As far as adjusting the main jets; if it needs richer, it needs richer on all four corners
if it was dialled in, with the prim/secondary jetting as you had it. If it was dialed in, I'd just go one size larger on all four and see if mph increases.
If it wasn't dialled in that close, then SOP would be 2 jets sizes up on either the primary or secondary and see if mph increases.
Then check the spark plugs to be sure WBO2 meter isn't misinterpreting what's going on.

Mattax - This AFR gauge is an incredible tool. Maybe you've used one. I made a spreadsheet that calculated jet sizes, metering rod sizes and what changes from one to another will do. And when I make a change to the actual parts, the AFR gauge reflects almost exactly what my spreadsheet says. Not that my spreadsheet is EXACT. There are factors in the real world that come in to play. But the spreadsheet is a great tool for RELEVANCY. What I mean is, if I want to go 1 full point richer at WOT, my spreadsheets are accurate enough to nearly always put me on the correct jet change right off the bat. No guessing. The AFR gauge confirms it. And it confirms there are enough real world factors that I need just a bit more or less to make it perfect. I swear, the buttometer agrees that 12.2 is the sweet point. I will get this to 12.2 at least by this weekend. Getting smoked at work and personal crap (working on my sister's car). For real, I don't need to check the spark plugs any more. The AFR gauge is so consistent, I can tell when its wrong or lying. It's only been wrong once before, and I could tell it was lying when driving the car. It had a problem and Summit replaced it for free.