Roller Cams and Crank Scrapers..

[BlackoutSteve]

What is the general consensus regarding the use of crank scrapers / windage trays together with (solid) roller cams?

I do wish to keep my oil under control with the use of a scraper, but have heard (unfounded?) recommendations that advice against.

In theory, the roller wheel and lobe interface have far less friction and would require far oil than a flat tappet. Also, most/all HiPerf roller lifters have additional oiling orifices that pressurize their axles and shoot oil directly onto the lobe, so is the Splash & Throw Off from the crank/rods still considered a requirement?

I have never heard anything against the use of scrapers when using flat tappets that have more friction and therefore would require more lubrication against the cam lobe.

Also, if scrapers are considered bad with rollers, how do dry-sumped engines with roller cams survive?

[Newold1]

If you are building an engine for sizeable power and rpms, oil control and windage is usually always an issue and many times a problem. With a good oiling system and solid roller lifters with proper oiling provisions in them I would always consider a crankshaft scraper and windage trays a must for a great build. In my opinion trying to oil camshafts and lifters off of oil splash from crankshaft and windage issues is a real bad place to start.

[cjperformance]

Control that oil ! Scraper, windage tray, baffle/s, kickout etc all good.
Any 'throw off' oil thats going to hit the cam and lifters is going to anyhow as it coming out of the rod bearings etc above the crank centerline and scraper before coming back down. The tray and scraper will help oil from below the crank centerline from being drawn up into the rotating assembly, there is plenty oil coming out above that to lube anything that may need splash lube.