I have a rear sump pan on my small block and I was unable to find a pickup and tube that went straight down in the pan. The pump is a Hi Volume. I ended up using a pump cover from an old Mopar dual pickup kit and a top fuel pickup screen that I've had for years. Result is the connection from the pump to the screen is a mixture of 7/8 fittings. I was wondering if this is too large?? Seems awful big. Should I neck it down somewhere and if so to what size??

It's OK

i agree. always feed a pump.

No such thing as too large on the suction side.

Excellent, thanks guys another little item put to bed!!!

i would be more concerned about the multitude of fittings used creating impairments to the suction, [possible cavitation ? ] than being oversize.

Me thinks that could be wrong, I wouldn't want dual 1.0 inch I.D. lines to my stock type oil pump
I have use a single #20 oil pickup hose to a old KB top fuel race oil pump on a blown pump gas Hemi motor I assembled that the customer furnished all the parts for and it work fine
As far as the Milidon dual line oil systems for BB and hemi motors they work a lot better now than they use to 30 yrs ago, I have never put a loop in a oil line above the inlet fitting to provide a small amount of oil to prelube the pump on start up
I have had the old dual line system loose prime after sitting when we were using stock oil pumps and adding the Milidon dual line kit onto them
That was a long time ago, that all stop when I started using the Milidon aluminum race oil pumps

Pump clearances have to be tight enough to create sufficient vacuum to pull cold oil up to the rotors. Also any minor leak in the intake side of the pump obviously is bad. So IMHO get a priming rod and test it. If it can't pull a prime fairly quickly at 600 drill rpm, I would be concerned. Scored pump rotors and big clearances have caused me problems with a single line system. Also sitting for a long time allows oil to drain off the rotors, making it tougher for the pump to pull a prime.