Has anyone played with crankshaft scraper locations on a dyno , lets hear what you found in the way of HP
I'm not sure what you could gain by putting the scraper anywhere other than as close to the throws as possible....
The real gain is in minimizing the oil level. Theres a lot of other things you need to look at to sucessfully do this in the kind of package you have to fit in most cars, but there are BIG gains in keeping the oil as far away from the crank as you can. Oh yes, another thing, a scraper is much more effective if the counterwieghts are round, rather than cam ground. There are SUBSTANTIAL gains to be had in oil control, but you really need to think about every aspect of what you are doing.
Thinking along those lines[oil level] would running a "marine style" or full sump pan be beneficial?? dave
Yes... but you have to make sure the oil will stay near the pump pickup during hard cornering, accels, and decels. This usually means baffles and trap doors, depending on the application (drag, road race, rock crawl, etc.).
IMO, which is pretty drag-centric, the BB mopar/late hemi set-up with external lines and a swinging pick-up is about as good as it gets for a wet-sump system. You can go a long ways down the minimal oil level road, but its not an "add-on", you have to take a holistic approach, starting with the clearances you run, and this puts a real premium on quality machine work. The Stock eliminator guys are the ones who have really taken this to another level, and they are stuck with a stock depth pan. The downside is there is a price to be paid in valvetrain longevity, especially if you are into a combo with a really big cam. Lots of oil to the top-end helps carry heat away from the valve springs. But there IS power in the pan.
On a genuinely streetable engine(realistic RPMs), with stock stroke, and a decent oil pan, a scraper isn't going to do anything. At the other extreme, high RPMs, long stroke, a poor oil pan, or oil level too close to the crank, can result in the crank picking up a lot of oil from the pan. One of the advantages of dry sump is avoiding that problem. As to oil flying off the crank, that oil slings off in every direction. The scraper only catches it at one point.
I would also consider a kickout on the pan to give the oil a place to go after it is scraped off the crank instead of "balling up" against the throws.
I should have made this a little clearer , Dry sump with scraper in different locations in the pan not just on the rail
What I posted is real world testing and experience, not assumption or anecdotal belief. But, if you don't believe it that's ok with me. All I can tell you is that it is good info. You would recognize the names of at least some of those who have invested the time, effort, and expense to investigate and experiment with this. They probably wouldn't appreciate my saying as much as I did.
The larger the "box" on the right side of pan as well as depth of the pan...is what is most efficent in a drysump Also a minimum of a 4 stage but pref a 5 stage oil pump Sealed valley with 1 stage scavenging valvetrain oil 3 stages sucking on the pan Sealed vc's Vent on the tank This way also creates a vacuum in in the engine of a approx 12-14 in with good ring seal Keeps oil pulled down off cylinder walls Lighter ring package can be used This will make more power than any scraper will Tony
The oil does not sling off in all directions, it clings around the crank/rods in an aerated mass. And yes, I want to hear the names of the guys who came up with that crock, feel free to pm me if its too "top secret".
I race with a very high rpm sbc (800+ hp). We find 17-20 hp with a scraper hand fabricated and biased to the right hand side. Run 8 qt Milidon Pan and use 5w-30 XRP racing synthetic oil. Street motors won't benefit much.... Just seen your added comment about a dry sump system.....rarely used and minimum effect. Hope this help !
I can't see why a scraper in a dry pan even more than one scraper would not be worth HP . The deeper the dry pan and 4 & 5 stages & venting is a no brainer. I just wonder if anyone on here has played with this
And getting it away from the crank as fast as possible. One thing I think some folks don't realize, is it's not just the spinning crank that causes the oil to be flung all over, but the pumping of the pistons in a 90* V8 creates turbulence. This turbulence is what will also churn oil, that's already in the pan, up. This is where a windage tray works its magic. It helps collect the oil being slung about, and prevents the turbulent air from directly churning up and aerating the oil already in the pan. If there is room in the pan you are using, a windage tray in conjunction with the scraper will aid in freeing up power and prolonging engine life with good oil control in a street car.
Wrong... The oil forms a "streamer" that is wrapped around the crank. Some guy named Yunick (heard of him?) got a slo-mo camera inside an engine and filmed the components under actual operating conditions. The streamer would dip down into the oil in the pan sump and replenish itself. They measured a still photo and found that streamer was over 20 ft long at 8000 RPM. That's where the original idea for a crank scraper came from. If you go to a parts house that still has one of those Lucas Oil gear models on the counter, you can see that streamer begin to form just cranking it by hand...a far cry from extreme high RPM... IIRC (from the book), they positioned the scraper to slice the oil streamer off as it came down past the "leading" pan rail. That kept it from picking up more oil on the way past. I believe Smokey mentioned that they got rid of so much oil that they burnt the valvetrain up on the dyno engine before they realized it was dried out.
Similar design to mine but I had no pics of it....several iterations were created and some helped and some didn't. The store bought screens didn't show any gains but the scraper does. I Also have to use a vacumn pump and run 9-11 HG of vacumn which is another 17+hp gain.
Depending on the particular point made, both of you are outright incorrect, or misunderstanding what you are seeing or what you read. You have plenty of company, so don't let me change your thinking. Smoky wasn't a dummy, but he didn't know everything, and like anyone else, he didn't always understand what he saw. He wasn't the god most think he was. Things he did and said over the years prove that, and his books document it in writing. Yes a crank may pick up oil from the sump, but that's not the same as high RPM windage, or the idea of a fantasy ball of oil clinging to a crank rotating at 5,000 RPM. George, Why would I PM you with more info? Your mind is already made up, and I don't feel obligated to convince you that what I posted is valid. I'm just some guy on the internet anyway, so believe as you wish.
This is my point with crankshaft rotation clockwise ,think were the oil is going coming off the scraper mounted on the pan rail . There has to be gains moving the scraper lower in a dry pan . This is taking in account of deep pan , vaccum pump , windage tray ect
Right away ...we have all started a debated We have also missed an obvious part of the equation.... We never asked what type of engine we are working on.....v8,v6,L4, chevy,ford,Toyota etc, While the basics apply.... We dont know if it's a high hp unlimited engine where gains found with scrapers described are debatable Or something small inch with many restrictions where your fighting for every last hp It also matters where the crank centerline is... Example. SBC vs a 426 Hemi or Y block style case Tony
Another really good point. I talked to a BBM SS racer who added a plate to the pan rail and kicked the side of the pan out 4", told me he saw 15 hp on the dyno over a conventional Milodon full-length sump/swinging pick-up combo. Dean Nicopolis used to run a similar set-up. Thats HUGE in a well scienced out SS motor. A wiper alone wont help as much in an FE or BB mopar, as the walls are so close, and extend below the centerline of the crank, and theres nowhere for the oil to go.
In my opinion, if there is enough distance between the crank/rods and the oil level and sufficient baffling in the pan, a tray can actually work against you. If the oil level is low enough, I think you are better off with a wiper and a kick-out, no tray.