Hello Fuzz,

When I started out, my goal was to get my 40-70mph cruising in the 14.6-15.4 range and my in D idle A/F appeared to be good in the 13-2-13.4 range. I am now running my 40-70mph (70 = 3400rpms) cruise in the 14.0-14.4 (.039" HSAB's, & .033" IFR's) range and my in D idle at 13.8-14.0 (.060" IAB's). These numbers are based on 10% E and 91 octane.

My main jetting is now 62's and my secondary jetting is now 74 (passenger) and 80 (drivers). The 62 main jets still show 14.0 at 4000rpms, so I know that my mains are in good shape. Note: both A/F sensors are within 0-.2 of each other during cruise conditions.
As of last weekend, my D side WOT is 12.8/13.0 and my P side WOT is 12.6/12.8. I just made a secondary float change this week to try and get the D side down to at least 12.8 at the leanest reading.

It appears by your part number that you have the downleg boosters which might be why you and I are so far apart on primary jetting, along with the engine size difference. But as long as the A/F is where you need it, then I say give it what it wants.

Have you messed much with the adjustable secondary linkage? I have tried both the 40% and the 60% and I like the 40% better so far.

Are you having any issues at a steady cruise then slowly accelerating creating A/F swings?

Are you able to control the rich spike when transitioning from cruising speed to WOT with your DP?

How is your cold start now that your in D A/F is leaned out to 14?

Thanks Fuzz