Crank scraper design

[Reaper1]

I did a search both on Google and on these forums, but I didn't find an answer to my question.

I'm designing my own crank scraper/oil pan baffle system, but I think I've identified an inherent deficiency in most designs.

Our engines are tilted back about 12*. All of the scrapers I could find have the scraper mounted parallel to the oil pan rail. Here's the issue, part of the scraper is found on the down-stroke of the crank throws, which is in the front of the engine. If the scraper is parallel to the pan rail, then this means the oil that is being scraped off of the crank will want to flow back toward the spinning crank. Typically the scraper is mounted directly to the pan rail with only a few drain holes. The other part of the scraper is on the back rail, which is on the upswing of the crank. Now, with an oil pan that doesn't have a baffle system to prevent the crank from sucking oil out of the sump this makes sense, but with a baffle that blocks the sump from the crank it's not as effective, leaving the front doing the majority of the work.

So, to address this problem I'm planning to mount the front part down past horizontal to force the scraped off oil to flow away from the crank. Has anyone seen this done, or done it themselves? Thoughts?

[wallace]

I'm not sure how much benefit you would get from an angled scraper...wouldn't the best "scrape" be at 90*? Another source of windage with factory rods is the oiling hole for the thrust side of the block that has to contribute to quite a bit of windage. One of the things I see on the really well designed oil pans is the kick out on the windage side (back of the block) with a knife edge that sticks out into the air flow to break it up and force it over into the kickout preventing that oil mist from hitting the rotating assembly.

[ShelGame]

All of the scrappers I've seen have the scrapper at the rear of the pan, and just a spacer at the front. But, you're right; if you put a scrapper at the front also, you'll want it to be angled away so that it doesn't drop oil back onto the crank.

[wallace]

I bought the setup from IJ and it has one in the front and one in the back pretty sure both are just flat to the pan rail.

[Reaper1]

Yeah, I have an IJ one that I was running in the original engine for the car. I'm making my own for my Masi build and this was one of the things I was taking into account. After doing the reading last night I have some more revisions to my design to make as I found quite a few good ideas that reminded me of things I wanted to do, but forgot over time. It was a good refresher! :)

[ShelGame]

Mine was an IJ scrapper, too. But it must have been an early one...

[Reaper1]

I want to point out that I've run the IJ scraper for quite a few years on a completely stock '88 TII bottom end. Yes, it required a bit of "adjustment" with a grinder, but this is TOTALLY expected! You can NOT expect a tight tolerance part like this to come out of the box and fit an engine perfectly as there are manufacturing tolerances that just can't be taken into account while making a part like this.

I NEVER have any issues with it. I sealed it with MOPAR transmission RTV to the block rails and held it up while it cured by itself with the pan bolts and the little installation stubs that come with the 1-piece Fel-Pro pan gasket (you can't use that gasket with this part, but I had some paying around). I then used just the end seals for the pan with a small blob of the RTV and ran a good bead of RTV around the pan. It NEVER leaked in the entire time I ran the car.

I can't say what, if any difference in performance this part gave, but I do know that I never had any kind of oiling issues, even at high rpm during fast transitional maneuvers or sustained high(ish) G corners. I'd claim that as a success.