Re: Which Oil Pump
Mark personally I don't feel there is ever a need to run a high volume pump on a sbc. There is a lot of disagreement between members regarding how much oil pressure is needed as well. That said, and I know some will dispute it, I'd run the high pressure/standard volume just like the Z/28 originally came with. Problem is it isn't available in the Select series with a bolt on pickup, which caused me to look at the next best option for me.
I looked through my notes again tonight on the Mellings Select pumps. The bolt on pickups are only available if you select one of the 4 pumps that come with 3/4" inlets. The standard sbc pump uses a 5/8 inlet. Since 3 of the 4 Melling Select pumps are race only versions I elected to use the remaining 3/4" inlet version. The only thing I don't like with this pump is it is a 10% increased volume pump. I can live with that, I know I didn't want the 25% high volume pumps. This pump comes with steel gears, shaft supports milled into the pump body and cover, provisions for bolt on pick up, heavy duty casting and many other nice features not found in the standard Mellings pumps. It also came with gears pinned to the shafts, not just pressed on and anti-cavitation grooves machined into the pump body. These last two features are shown as only available on the race version pumps, but mine had them when I disassembled it. Mellings also reduced the end play in the gears to minimize distributor spark scatter. The part number of my pump is 10552.
Some here have suggested that Mellings stopped producing these pumps with steel gears a while back, but mine came with them last year and Mellings is still advertising them as such from what I've seen, or dealers are using old data possibly? Bottom line is I'm really sold on this pump and since Moroso won't answer any questions regarding if they accidentally used or still use the weaker casting Mellings pump in their blueprint series I'm definitely not using their pump. Not at least until they can confirm they aren't selling the weaker casting, which to date they haven't done.
I think Summit lists the 3 or 4 different length bolt on pickups for these pumps. My pickup tube arrived from Summit with a little bit of localized surface rust on the outside of the tube. If yours arrives in this condition, Summit verified this existed throughout their stock, they will credit your charge card for the purchase price of the pickup and let you keep it. Pretty good service from Summit, I've always been very happy with them.
By the way I do plan to run the high pressure spring that came with my 10552 pump also.