Oil drainback on aluminum heads?
 

I've been doing some serious cleanup on my new Black Friday Special SM heads which really got me to thinking, is there something we can do to help get the oil back in the pan?

This head is approximately 45 degrees and you can see how much oil could collect on the edges before the oil is high enough to drain back.

I could be over thinking this, any thoughts??

We have done the same as post #6 here....

https://forums.maxperformanceinc.com...ck+drain+holes

Also oil hole radius and polishing.

The first generation Edelbrock heads were notorious for issues.

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I work and massage the drain troughs/holes that already exist. Haven't worked on any SM heads, but since they are a replica/copy of the Edelbrock heads, they should behave the same. I widen and polish the trough all the way to the spring seats, polish and enlarge the entrance of the hole making it more of a funnel shape. Lower it a little. Just removing all the sharp edges, smoothing and polishing the drain path, makes a big difference.

I bought my 330 CFM eheads from Dave at SD Performance. Although they have the earlier combustion chamber design Dave did modified the drain back holes to improve drain back. I think the need for putting on the external hoses for improved drain back may be somewhat dependent on the RPM that your engine is running at. Because of my cam specs my converter stall is 4,400 and I shift at 5,600 and shifting any higher does not improve ET or MPH. So at my RPM I don't believe I have any oil starvation issues. If I was shifting at 7,000 or higher then I would definitely install the drain back lines or get an accumulator to prevent oil starvation.

A restricted pushrod will slow the flow to the top also. I put drain back lines on the race engines I do.

I'm playing with this some more, here are a few pictures. I couldn't find any playdough so I used a piece of cookie :o to illustrate what I'm thinking.

At a 45 degree angle and NOT accounting for engine tilt or enertia during acceleration/braking, the ruler give an idea how high the the oil drain holes are.

I was thinking of cutting a groove in the valve cover bosses to smooth out the oil draining from front to back. I would also put in some high temp putty or tap and plug those two freezeplug holes and some putty at the back of the head around a couple of tapped screws to eliminate the void and help get the oil back to the drain back line like Steve C. suggested on his post represented by the black dot.

I run .030 restrictors on all my solid stuff and has served me well.
The High Ports currently in service look to have fine oil return-drain back qualities.
No where for oil to puddle up.

Here's what I did to reduce the resistance and allow the oil to drain to the back of the head. The dot is approximately where I'll plumb a line from there straight to the pan. Probably a bit overkill but... I have time to kill anyways.

A bit more progress. This is a 3/8" barb fitting, I'll be using 1/2" barb fittings (1/4npt) along with 1/2" braded line. I also ordered some 1/2" bulkhead fittings for the pan.

How about steel bent lines over your headers instead of rubber please
I love the work just don’t want to see it go up
In smoke literally

I use the Teflon steel braided lines with crimp.on fittings. No rubber. Weld in bungs to the pan to accept fittings. A 90 will usually work on both ends

Still doing some mockup work on this project, I had to wait for some 90 degree bulkhead fittings to get here. No worries, I'm not using this clear vinyl tubing for the finished project. I'll either use oil cooler hose or perhaps 1/2" aluminum fuel line and compression fittings. The engine is rotated pan up on the stand, I rotated and cropped the 2nd and 3rd picture for clarity... no Newton defying here LOL.:o

Just an opinion here. Get someone to weld fittings on the oil pan for you and tap the heads for fittings and use a teflon inner liner hose with braiding on the outside. Get the hydraulic shop to put ends on the hose for you. I know it's a bit overkill but no worries after.
I got my lines done by a company called Greenline hose here. I welded this fitting to the oil pan. and used a 90 degree fitting to position hose.
https://www.summitracing.com/parts/s...7b?seid=srese1 You can get these in steel cause oil pan is steel.