I'm going from internal to a single external line system, with a KB pump, do i need to loop the line high to stop drain back, as many years ago i ran the dual line system and had to pull the dist and spin the motor over every time i took the race car out and would like to avoid doing that again.
Mick

The old KB rotor design was notorious for losing its prime. Not so with standard Mopar rotor design.

The one i used to use with the dual line was a milodon, i'll be using a KB this time as i picked it up at a good price and it's never been used.

I angled the fitting into the pump up so to trap some oil at the pump to keep it primed but I use a HV not KB

I put the trap in my old 383 destroker that
had a single line external set up.. had no
issues at all

Be sure and look at the fitting that goes through the pan into the pickup. I had to cut a bunch off mine to get the max flow area where the fitting ends inside the pickup. I beveled the end of the fitting as well.

I've got a dual line Milidon system with the Milidon oil pump on my race car, it has never lost it prime in three years now
The Milidon cast aluminum pump with the front entrance hose nipple has O rings on the bottom of the pump(no gasket) to the block so maybe that is the key to getting them rascals to keep from loosing the prime

Wear on pump rotors will cause a loss of prime, and some oils, like the old Kendal. "green" oil helped a lot.

This is what I did as well

I try to keep as much of the line below the oil level as possible. Never had issues

This is what i was thinking of doing.
Mick

Milidon has a new pump housing and rotor design that is very nice. If I were running an external line, I would look at either their pump body with the line going into the side of it, or this new pump body with the 3/4 " plate and cast-in fitting that bolts under the pump body. It eliminates the need for that big pump cover with fitting. Seems like a cleaner set-up to me.

Maybe AndyF or someone has tried all these combinations, checked any flow variation and has some input.

I never heard of anybody running a KB with a single line. Are you going to feed the top plate, or the bottom of the rotors, or T the line and try both? It's not like you can call KB and ask......

I raised the line also to make a trap on my 505 stroker and Hemi. I don't know if there is bleed off or not as I also use a Moroso accumulator to prime the engine before start up. Oil pressure starts to move on the gauge before the engine starts . Make sure you have the braided line away from the header tubes

I will not run or use that thin Milidon plate for the second external pick up hose, it is a way to much of a blockage to good oil flow for me
The Milidon cast aluminum pump with the fitting cast into it for the second line works really fine

Don't know about the KB pumps Mick but I used the Milodon no. 21000 kit with Melling HV pump, 2" deepened stock sump, primed it once after rebuild and never had to after, ran Quaker State 20/50 back then, 20>25psi idle@900rpm and 65>75psi from 3500>6800.

Pics of the pump, i'm not sure which fitting does what, so a little help wouldn't go amiss.

The pump has 4 fittings. 2 are inlets, 1 is pressure out and goes to the remote oil filter and 1 comes back through the pump casting to feed the motor. The one in the top cover is one of the inlets. The one closest to the words Keith Black cast in the main body is the pressure out (to the oil filter). The next one is the other inlet. The next one is where you come back from the oil filter into the motor. The fitting on the top is reversible. Normally you would swap that around so it points to the back. I love KB but the trend today (for applications less than 2000 HP) is less volume and pressure, neither of which the KB will give you.

So, let me see if i've got this right, the blank in the back of the top cover is where the feed would normally come from the sump, the bottom one in the top pic on the main body is the outlet to the remote filter and the top fitting on the main body is the return from filter ?