We were sponsored by Holley for 3 seasons and I really like their carburetors. I found some of the following information in some old tuner's notes and FAQ's I have written:
Steve,
Thanks for the compliments. Here is the data you requested...The white cam (#218) often discolors and looks pink or orange. The accelerator pump cam kit (#20-12) contains (
pump cams. Screw position #1 yields the fastest shot and the least duration. Screw position #2 yields a longer duration pump shot as does screw position #3.
The cams are listed by color and pump volume from lowest to highest:
White, Blue, Red, Orange, Black, Green, Pink and Brown.
I would also recommend the hollow discharge nozzle (squirter) screw available under part #26-12. This is not normally used under a .039" squirter, but I like to use it in conjunction with a .028" nozzle. This works in 99% of Holley street applications, even with a fairly stout camshaft and low manifold vacuum.
Keep going up in shooter size until a puff of black smoke comes out the exhaust, then go back one or two sizes.
Hope this helps...Robert