Don Terrill’s Speed-Talk

Engine pumps LOTS upstairs. What is the best baffle to keep excess oil out of the pump?

Increase the drainback areas and restrict some excess oil from upstairs is almost more effective that trying to get breathers to do all that work.

Newold1 wrote: ↑Tue Sep 18, 2018 7:36 pm Increase the drainback areas and restrict some excess oil from upstairs is almost more effective that trying to get breathers to do all that work.

And how would you do that on a complete running engine?

Didn't this come up recently?
Where is your valve cover outlet located?

Depending on where is valve cover breathers are or will be located in his valve covers, the effectiveness of the baffles from location will matter. If he just has a lot of excess oil and accumulation hanging around and being whipped by the valve train no baffle and location may correct the problem so obviously the best solution is to possibly remove the heads and try to improve the situation with possibly the things I mentioned in my first post.

Kind of related.
One of the Nostalgia Top Fuel teams that use the old 392 Hemi derivative moved their puke tank "breathers" from the valve covers to the valley cover. When there are no unscheduled disassemblies occurring the excessive problem was 90% improved. As newold mentioned much less frothing might be happening there. They still made their new breather outlet baffled.

This seems like an easy thing to try on a Tunnel ram engine. On a chevy, perhaps add in one of those valley lifter shields to the mix. Anyone still use those?

I have a 440 mopar with a vacuum pump, I had issues with it blowing oil out the puke tank breather in a 1/4 run. I still have to drain it every pass but it's not really a lot any more. They tell me any air leaks in the crankcase causes this problem. So I used a smoke machine to pressurize the crank case, had minor leak on the oil pan and at the rear main seal. Got a special double lipped seal, and fixed the oil pan gasket. I then moved the pump intake to the valley pan and fabricated a baffle. Also don't use the dipstick, have a tube, but it has a rubber cap I can take off to check the oil. I put a sock over the filter on the puke tank, just to catch any droplets. After all that I get about 3 ounces each run out of the tank. I am sure I could get several runs with out draining, but I just don't want to be the guy that puts oil on the track.

Dave. In a longer discussion on engine breathers on here, most gave the impression that to Place them in the valley was a no-go on a drag engine.

Valve cover should be the "best" Place to put them. I would assume high, up front... Now, do results show the lifter valley to work as good or even better- depending on...?

Just wondering.
Did anyone in that thread have A-B tests to verify that or was it passed down beliefs?
The example I gave was a blown nitro app which is usually pretty intense on the pan pressure.
It may or may not relate to anything NA but worth pondering and perhaps trying.

Many things contribute. But you need to make sure the engine is sealed up first. A leaker will suck up oil.

Also too small of a hose will pull oil. Use the largest diameter hose you can.

Like mentioned before drainbacks and amount of oil going to where you pulling vacuum from should be checked.

Crankcase pressure: it be correct to assume it's Equal- under the valve cover VS valley cover? Unless, there's a seal somewhere between the two.....
I think you are right, Dave. Lot less oil splash under there, as you say. Even less if you have a lifter Shield (which also stops hot oil getting the intake hotter...for a short period of time).

I might have to look up that thread. The Logic behind it was.... something to do With drainback? Maybe a smart guy said pressure under valve cover stop oil getting through the pushrods?


Baffles: I have seen some AN fittings With Integrated baffle. Did not find any when I looked for buying. Ended up With some Summit- pieces. Seems the have some desireable features, although I'd do them different.

https://www.summitracing.com/int/parts/ ... /overview/ Add some steel grid? I'll weld on AN 12 male weldbungs. Could be used on valleypan too, I Guess.

Well,.. I assume the goal is to pull or push air and not so much the oil.
I only know that the oil return on my BB heads is not so great even after carving here and there.
The angle of the dangle, pressure and g forces is not helping gravity do it's job.
It's always a flooded mess up there, which is a good thing I think.

Not so fond of cutting the oil off through the pushrods anymore. Restricted maybe but eliminated, no.
Had a Rodeck solid block with no upper oiling. That was fine when 600 lbs open pressure was the norm.
When it became 1000 lbs I could not keep pushrod ends alive more than 2 laps.
This in spite of all kinds of trick of the week goops and coatings.
I then learned how to drill really long passages through the lifters using my vertical mill.
End of problem.