Dry sump Vs wet sump
This is an unknown, but 3/5 bhp is reasonable.
Conjectureboy
Mark, I assume you are indicating that the dry sump may be worth 3/5 bhp more than the wet sump system in the "Gernade".
(if not don't bother reading the rest) 
In one of Smokey Yunicks sb chevy books he states "Make no mistake, switching to a dry-sump will cost some power".
He says in the sb chevy "at least 8 to 10 HP or more over a wet-sump".
So is this windage vs dry sump pumps?
What's your take on this?
I'm not questioning your knowlage on this, I'm just trying to increase mine. 
Thanks, Don
Warning Disclaimer: Non Milwaukee Midget, non BMC, non Rover K16, historical, technical, footnote . . . . . . . 
Hi Don,
Sorry it took so long to answer this. BTW, this info is based on my observations of dyno data from various engine types. There is a certain "consistency" to that data. And also, the "timeline of my memory" may have faded a bit as I have aged, and might be slightly "inaccurate".
Back in the "dark ages", (the early 70's ? ? ?) dry sump systems were looked upon with disfavor. This was mostly as a result of Smokey's statements and writings, AND, the disdain Bill "Grumpy" Jenkins had for them. AND, if you just bolted on a "standard" dry sump setup, and then tested it back to back with a "racing" wet sump, you might "lose" power. Hence the pronouncements.
BUT, what was going on here?You need to remember a few things here about the specifics of the situations:
A/ Drag cars only need "effective oil control" for a few seconds. And it could be "managed" with deep, rear sump, wet pans. Additionally, Jenkins was one of the first to exploit "crank scraper technology", a "feature" which added bhp.
2/ Oval racing, while longer in duration, again "pushed" the oil into a "controllable position", which could be "managed" with special oil pan/baffle construction. Due to Jenkin's connections to certain Nascar Chevy teams, the crank scraper tech migrated to ovals, gaining bhp. Yunick also started using crank scrapers around this time. Some of this "technology migration" was due to the influence of the Chevy "Skunkworks" racing engineers.
d/ Meanwhile, down at Rattlesnake Raceway in Texas, dry sump oil control of SBC's & BBC's for "road racing" was "required" to get engines to live for a race duration. Bhp losses, if any, were just "accepted", since without a dry sump, engine life was at best, a "crapshoot".
But then, 2 things happened. Crank scraper technology migrated into road racing engines. I'm uncertain who may have done it first, whether it was Hall, Weiss, Traco, or McClaren. And it doesn't matter, because it was instantly copied by everyone, since bhp now went up. And it created oil mass control issues, so additional scavenge stages were added, AND, bhp went up again. Successful race engine builders are typically observant and clued-in guys, and the good ones exploited this information "to the max".
Eventually, enough scavenge was used and "depression" was created in the crankcase. This "created" other opportunities for potential exploitation.
And so on, brings us to today, where so little oil is allowed in the crankcase that "oil squirters" are required to get parts to live for the requisite distances.
Is it still possible to bolt on a basic dry sump system and lose bhp? I don't think so, but, anything is possible. BUT, I have never been disappointed by the dyno results from a "sophisticated" dry sump "system". This is another situation where you get what you pay for.
It pays to remember that "evolution" in racing approaches the "speed of light" at the professional levels. If you don't evolve, you get "left behind", and that brings on the expected consequences . . . . . . . . . .
"Those who do not learn from history, are doomed to repeat it." Please excuse my "liberal" interpretation of the G. Santayana quote.

Historyboy