Oil Return Mods for HP Gains on Small Block

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Rocket

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I have read many articles about oil system modifications for small block engines but there was never much indicated on how to ensure quick and efficient return of oil to the pan to minimize windage around the crank and cam. I have seen pictures of small plates bolted over the cam tunnel but not much more than that. Any information out there that would benefit a performance build?

Thanks
 
What are you going to use the engine for? NHRA type drag racing,
towing a heavy trailer, snow plow/work truck??

A windage tray is all you really need, the factory oiling is pretty good,
Milodon makes one too.

Perhaps a Mellings oil pump would be a good idea.

I suggest using the Mopar cam Thrust plate, {timing slack reducer} kit.

http://www.jegs.com/i/Mopar+Performance/312/P5007709/10002/-1

Mopar Performance # 5007709

Mopar Performance LA TIMING CHAIN TENSIONER
312-P5007709.jpg
 
What type of camshaft are you planning for? What usage are you expecting? What oil system?
 
Lots of work for little gain, unless you are building a balls to the wall race engine.

Don't get hung up on those mods used in Engine Builder, shoot off, dyno competitions.

Get a windage tray, de-bure (remove the casting flash) from the oil returns in the block and heads.
 
Thanks for the reply's. I am building a bracket racer - low 10 second A body. Currently running a solid lifter cam but may go roller next time around. I have the windage tray and a Hamburger aluminum rear sump pan without the kickout. Just trying to see if there are any little tricks out there that I can apply when I pull the engine this winter.
 
For a bracket car I wouldn't worry about it. If you want to get better oil control, add a scraper to it. But as far as controlling the drainback, the cam NEEDS oil, and flat tappets especially. If you go solid roller you can do more, but the best way to ge the windage losses minimized is to remove it from the slipstream with a good scraper. Even beyond a windage tray. You can also set the clearances and modify the oil galleys so you can run a thinner oil and lower pressures to get some "free power".
 
Is it wise to run a scraper AND windage tray for a street/ strip engine?

If so, can anyone suggest a good brand scraper?
 
Gylptol the inside of the engine along with deburing the ruff casting flash. Done.
 
I like the idea of a windage tray in anything. I think it helps and when properly designed does a good job at keeping oil in the pan. The craper simply removes it from the airstream it doesny help keep it from whipping up in the first place. The tray does. There are real gains to be had in oil control. But with a flat tappet too much oil control on a street car is pushing it in regard to the lifters and camshaft relationship. I drill a few extra drainback holes, remove the flash and bumps, and smooth the existing holes to make sure the oil can get down quick. But I want plenty to come up and oil the cam too.
 
Where are you drilling the extra drainback holes?
 
All the R3 blocks I've had don't have any drain back holes in the valley at all. When I questioned MP about it they told me a single 5/8 hole at the back of the valley was sufficient. Granted I haven't built an R3 yet (I had to sell them) but that seems a little small to me. My current engine has the holes over the cam covered (solid flat tappet cam), and a windage tray. I've been comptenplating a scraper and a rear sump pan for the new car but the same engine.

As an observation though I didn't really notice any gain from the engine with the windage control and drain back mods from the the first incarnation that was just slapped together with no windage control because I had to be racing again within the week. So in retrospect it may not be worth the effort in a bracket engine.
 
most top engine builders will not want drainage from the center of the cam tunnle to eliminate oil falling on top of the crank and rods creating more windage, smoothing the path way towards the back of the block as fast as possible to get it back into the sump of the pan is the most desirable. there are some more modifications to getting the oil to the back of the block.
 
I add a few in the webbing between the lifters and cam tunnel to supplement the stuf the factory does. I also beldn them so there is no low area to hold oil. I want all the oil I can to hit the cam, as I said, my concern is life at idle on the street for the cam, not so much windage control. Also, the cam is splash oiled from the bottom, not the top. So you can stop the oil from dripping down onto the cam all you want. You want the oil to splash up off the crank and hit the cam from the bottom. That's why MP didnt sweat the holes. They let them go for maximum strength. You could also use the EDM lifters and completely surround the cam if you wanted. But it's a lot of work. I'd estimate 70% of the loss from windage is controlled by a tray and scraper or just scraper. The other 30% is a small figure for the effort and possible risk IMO. Were talking 0-30hp at best on a 500hp engine. You'll lose more than that on a hot day due to weather. Mal, the scraper pulls oil off the crank that "could" be splashed on the cam. So it could be an issue on a fast rate solid with a high spring load, or a roller where it just wears out the lifters faster. Or it might not be an issue at all... The big power producer is a dry sump. If it's a race car, dry sump will free up a lot more power, but is expensive and hard to package.
 
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