I have a fresh 302 Ford, flat tappet, rv cam, 10.5:1 comp, edelbrock intake, 600cfm carb, headers. It was a basic rebuild and has been running (in my garage) for the last year. I used rotella for break in, dumped it, ran a 10W30 with comp-cams additive for a bit while starting and working on tuning it in my garage. Last year I switched over to a 15W40 collector auto oil that has a good zinc content and is formulated well. Now the ford oil pumps dont do well with high viscosity oil and I was wondering if you guys think the 15W40 is too thick? I put in an ARP oil pump shaft on the rebuild so faillure of the shaft isnt likely. Just curious if there is a product out there that I would switch to that is a little lighter but with the proper zinc for my flat tappet. Thanks!