So the pan Matt buckey has on his 540s is a CP 219LT, he built the engines himself, brought them to me to dyno/tune. On my dyno, oil pressure seemed fine, in boat he sees a drop after staying in it much past 3500/ 4000 on up, he lowered oil level, it got better ( tells me its NOT because its flooding top with oil plus his drain backs in heads have been extensively opened up), he lowered level more to point hes got like 7 qts in pans instead of the 10 or 11 but says he still sees a drop to like 40 lbs form 60/70 but it drops LESS being ran on verge of sucking air. Oils no warmer then on my dyno, rods, mains are middle of road on clearance.I told him to put valvoline racing oil in one engine because it has alot of anti foaming properties. On that engine it drops less then other one when he stays in it, same weight, 20/w 50 but eventually it still drops. I feel his windage tray built in pan is too far from crank and its whipping up the oil, oils a big ball around crank. His plan is to pull them, have me pull pans, take windage trays bolted in pans out, add crank scraper and a stud mounted windage tray that are closer to crank throws then run them on dyno at 4000 for 5, 10 minutes vs 10, 20 seconds.
Now, in your case, your champ pan is a different part nu,ber, maybe its better plus it WILL be better then the piece of tin gm puts in and a stock pan

if possible could you run it on the dyno first to see what happens so you have a before and after based on time. also any chance that part of the problem is the boat? i.e. the angle of the motors when running vs sitting on the dyno. any good way to confirm that the oil is in fact foaming and it is not some thing stupid like the oil pump bypass changing with prolonged heat. just throwing stuff out there.

Looks like the only difference in his and mine is 1/4 inch of depth with his being deeper...kinda has me nervous now! Any suggestions or mods I should look at before I install it or just put her in and hope for the best?

Very interesting read! I might also Have weird problems with high rpm oil pressure with My milodon, Pan, full sump, kick Out, Trapp doors, windage tray, etc

Pleased let us know know The results, i Have exactly The same problem after i replaced The stock merc 8qt Pan with milodon 31180 Pan. I also switched For Johnsson lifters with axle oiling at The same Time, no others changes.

The oil pan is such an important part that gets overlooked.
I`ve always had pressure issues due to aeration, even with the best marine pans I could find.
Got tired of losing pressure on almost every engine and went external oil pump for that reason.
Got better but not great.

Eddie has custom oil pans built just for this reason to his specs.
These are the first engines I`ve had where both oil pressures are solid as a rock no matter the RMP or how long I run the boat.

Whatever he`s doing is working perfectly. No fancy oil pumps either ..

Whatever you do don`t skimp on oil pans. I don`t know what to tell you to get because I thought I was getting a good pan (canton marine) and still had aeration problems. The longer I ran the boat the lower the pressure got.


Eddies:


https://cimg1.ibsrv.net/gimg/www.off...a0e618703b.jpg

Your right that it might be ight be angle of the boat, i hadnt gave that much thought, we narrowed issue down to.oil control for sure because lowering oil.level to point it almost sucks air helped on both engines. Racing oil w more antifoaming in just one engine as a experiment prolonged time it takes over other one. Once it happens, he can lean into throttle and watch it drop. On my 1100 ho blower engune I had in my Baja, I had a 14 qt Hardin offshore pan, I could stay in it at 6300 prolonged after cruising at 4000 and never dropped. Customer knows the 14 qt won't fit amd 12 qt they sell probably won't fit.
we might try to duplicate it on the dyno befire tearing into it, I'll post a update if we do.
now answering a few other comments, I had a customer bring a 588 with a 5 3/8 stroke and "milodon stroker pan", it windaged so bad you could see it in 6 seconds on my dyno. You could literally bring it up to 4500 at 300, 400 ft lbs of tq partially loaded, accelerate it and watch oil pressure plunge from 70 to 40,50. He changed to a moroso race pan while it was still on dyno (yes, he layed under it on stand) and issues were gone. Another customer brought a 540 with same pan, did same exact thing, he changed to a Hardin 10 qt while on the dyno and it was fine, Smitty

Very interesting that this seems to be a trend to some extent...seems like the Hardin pans work well just going off what dan and artic just posted....wondering if I should just sell the champ pan and get a hardin...don't think this will end up on a dyno before it goes in the boat and would really hate to have issues and have to pull the damn engine....again hahaha

Oil pan angle is definitely a factor. Once the oil becomes entrained like egg in a beater, it doesn't want to come off.

Tight crank scrapers increase windage drag, but may be necessary for perf marine wet sump.

Darin Morgan has a great vid on windage/oil issues from about 3 months ago.


He also shared a photo recently showing the main bearings with lip seals to capture the bearing oil and drains them through pipes in the caps to the pan.

Eric Weingartner has a vid on oil level in pans on the dyno. There was quite a bit of hp difference in the higher pan levels. I thonknthere was some oil pressure factors as well.

I saw the 496 oil pan video, I've experienced pretty much same thing on my dyno. At one point I bought full featured 10 qt canton pans for my new boat, had kickouts, power pouches, they threw everything under sun at them. I put one on my 4.250 stroke blower motor out of my Baja minus the blower and fought w oil control over 5500. There were non pan related issues involved though too, early v1 afr heads without enough drain back. I would suck pan dry on dyno and twitch the oil pressure when it sucked air. I pulled heads off on dyno and tripled the drain back area and have on every aluminum head I've ever installed ever since then. Back together I still starved the oil but not as bad and not until 5800, 6000. Adding oil past what you were supposed to use made the twitching go away bit I then had windage issues and could make the oil pressure drop steady but not twitchy at higher rpms. Talking to canton they told me "yeah, we've heard that a few times and sometimes they don't work in certain applications , why are you revving it so high", you need a dry sump? (6300). Then to add to that, joe garafalo (mild thunder) bought the cheaper version for his 454 blower engines with half the features and had no issues (less stroke though).
I then rxrd the pan on dyno, mashed all the trap door springs so they flapped easier and it was OK at higher rpms but i didnt trust them since it was so touchy on level to sucking air or having windage with too much. In a boat they might have been fine since the engines would be tilted rearward some but i didn't want to FAFO, smitty
Since then I try to buy pans for stroker engines that are only rated for the stroke I'm using, ie, 4.250 stroke, pan company's says clears up 4.250 stroke w steel rods with idea that the scrapers and windage tray are close enough. A pan that will clear a 4.750 stroke on a 4.0 or 4.250 stroke engine is so far from crank the features dint do their job. Then it's time to put a stud mounted windage tray in that's closer