An oil accumulator?

Thinking of building my next BBM engine with a dry sump, do you need an accumulator with a system like that?

You could, but the design of a dry sump system is to reduce the risk of pressure loss by having a storage tank of de-aerated foam free oil with the oil feed at the bottom of the tank to negate the risk of pressure loss during hard cornering and acceleration. There is always a risk in any system I guess,
like if the belt broke to the scavenge/pressure pump. With the B engine pump being external, one could use an external fed pump on the block to feed the engine and just have a belt driven pump for scavenging.

We never used an accumulator on the Sprint Cars or vintage TransAm cars, over multiple seasons.
The Achilles Heel of a dry sump system is the pump belt: debris or breakage is possible, but we never had that issue even on dirt.
A warning light for pressure loss is a good idea, just like with any oiling architecture.

Very few dry sump systems include an accumulator since there is no danger of the system running out of oil. Pre-oiling is easy with a dry sump since you just remove the belt and spin the pump. Spinning the pump works for new engines, or engines that have been sitting a long time. If you want to pre-oil before every start you could hook up a small accumulator to the main gallery with a remote valve. Then you open the valve before starting the engine and close it once you have pressure. I've never seen that done but it would be simple to add if you don't mind the extra complication and expense.

Most I know using a DS system have no accumulator. Also, as has been said priming is pretty easy if you package things well because the cog belt will slip off by hand.

Thinking of using the Missile system...for the pump. Would prefer to stay away from belts. Is there any other options?

https://www.racingjunk.com/oil-pumps-pans-system/184443004/missile-hemi-dry-sump-oil-pump.html

Peterson makes a filter mount with a built in pump for priming and prelubing, turns with a cordless driver. S/F....Ken M

https://petersonfluidsys.com/filter-LargePrimerRemote.html

I would not bother with the missile system. If you want a dry sump then buy a true dry sump system, not one driven off of the cam gear. No need to accumulator on a true dry sump. Can either take the belt off and spin the pump or you could buy Peterson remote filter mount with a built in primer.

Al, Thanks for that tid-bit, I might just get me one of those... Beats pulling the Mag to prime.

Good advice, I wouldn’t recommend the Missile either

I run Barnes dry sump, also have Peterson remote with Primer, not had any issues with losing a belt, Primer is an excellent acquisition, very pleased.

What ever pump you decide, cast iron pressure section if available is a good move

Another option is a wet sump with a belt driven pump. I ran this setup on a low deck 470 and it worked great. Moroso builds a really nice rear sump dragster type of pan with a AN-20 fitting for the pickup. The Peterson pump is the same as the dry sump pump and it has a fitting on the back so you can drive a vacuum pump off the same belt. So that cleans up the front of the engine a bit.