Dry sumping a BBC
 

Hello all.

A little background first:
I bought a 2001 supercat 522 (.060 over) engine from ilmor last year for my 24-7 pantera project. It will be de -tuned to run on pump gas. The engine came set up for a dry sump oiling system and I plan on keeping it that way. It came with a custom aluminum pan that was used with a marine bellhousing starter and I have a bravo that takes a conventional starter so the pan was useless to me.

I had a pan made and bought a barnes five stage pump, a bunch of -12 hose and fittings and fabricated a pump mounting bracket. I have a parallel filter assembly that came with the engine and will have a 10 to 12 qt. oil tank with -16 fittings made.

Pics of the pan:
http://i205.photobucket.com/albums/b...ps7fb8e2b9.jpg
http://i205.photobucket.com/albums/b...ps9f7b93fb.jpg
http://i205.photobucket.com/albums/b...ps0c50fead.jpg

Pics of the pump:
http://i205.photobucket.com/albums/b...ps7a64d1d6.jpg

According to the folks at barnes, I should drive the pump at around 60 to 65% for a marine application.
I'll be using a CV products "twin pin" HTD belt and pulley system for the pump drive.

I'll try to keep this thread updated with everything I learn so others thinking of giving it a go can see how I did mine and get ideas.


Any thoughts?

REmember..its better to dry sump than to dry hump.....

I try to talk all my customers into dry sump for many reasons..........thanks Rob (phragle) now I have 1 more reason.

Hey Brian.
Can you elaborate on the benefits of a dry sump system on a marine application?

Is this hearsay or is this the voice of experience?

Higher volumes of oil can be used in the system. This allows the oil to run cooler, last longer, and also de-gas better (from ring blow by). The pan can be much lower profile, meaning the engine can be dropped for a better CG. No sloshing issues so extreme cornering or pounding from waves will not starve the pump. Pressure can be adjusted. External oil pump, so it can easily be serviced. Basically a dry sump system is better in just about every way, but they can be a little pricey and are also more complex.

Other benefits are the crank does not have to fight its way through the oil splashing on it, constant vacuum inside engine so no oil leaks and more HP. The only negative is the cost.

All good points brought up by SS930 and Brian41. My buddy that I drag race with, runs a big cube SBC (approx 500 CI) that is a dry sump. He spins it hard too. Ther was more up-front cost, but everything else is a plus. Including, it just looks nice!

I would imagine in a marine application, all of the same advantages apply, especially the larger oil volume with the tank and the lower CG.

In a system with 4 scavenging pickups on the pan, what kind of crankcase vacuum can I expect and what does that do to my piston ring selection?

I plan on 2 -16 return lines to the tank and 1 -16 supply to the pump from the tank.
Also 1 -12 supply to the filters and then into the block. As stated earlier, it's a five stage pump with 4 -12 scavenging pickups

Also, due to the expected cooler oil temps due to the increased oil volume, I was hoping I wouldn't need an oil cooler. Am I crazy on this one?

Also, any thoughts on venting the system?
Should I have a vent in each valve cover and then another on the top of the tank?

And if the belt falls off/breaks! :D

I thought of that but, the HTD belts are supposed to be the bees knees, the engine is enclosed and not subject to road debris damaging the system and ensuring good alignment should mitigate belt failure. The belt orientates itself via a "hat" washer on the crank pulley and, if aligned correctly, centers itself on the driven pulley.

But, yeah, it would suck if you lost the belt! Lol

Pressure switch should be all that is needed.

You need the oil cooler or you will need a new engine.

I do have this mercruiser oil cooler. I think it's the hp502 type but I'm not certain. It has 1/2" NPT threads on the oil in and oil out. Would this suffice for flow and cooling capacity?
Pretty sure they make a 1/2"NPT to -12AN fitting.
http://i205.photobucket.com/albums/b...ps891419c0.jpg
http://i205.photobucket.com/albums/b...ps5a044178.jpg

You will want a thermostatic oil cooler that will handle your HP goal +20% to insure proper oil temps. Never lost a belt and proper tension will keep the belt centered, to tight they walk to the front of driven pulley. You should be able to slid the belt back and forth on the driven pulley with your fingers with moderate force. We run 4 stage pumps up to 600 CU and regulate the vacuum to 6-7 inches. No breathers on the valve covers, vent the system from the tank to your flame arrestor. If you use a vent tank you with always have a oil smell when you come to a stop after a good run.

Yup, they sure do.

Good tip.

Thanks for the replies guys.

So, if I use a bypass thermostat on the oil cooler will the cooler I have work with the 1/2" NPT in and out?

Brian, how do you regulate the crankcase vacuum and what size vent hose to the flame arrestor?

Thanks, rob

Only use that used oil cooler if you know the history of it ,if a motor has ever gone bad like spun a bearing with that oil cooler it is scrap buy a new one.

I reverse engineered them from Moroso vacuum pump system and they worked great.

Does the forward facing barbed fitting off the valve cover vent to the flame arrestor? I'm trying to wrap my head around how all the vent hoses get plumbed. Am I correct in thinking that you tie the two valve cover vents and the oil tank vent together and vent the whole system to the flame arrestor?

Thanks for taking the time to reply and post pics. Much appreciated.

Vent goes from the top of 1 valve cover to the vent "in" on tank and then another hose goes from vent "out" on tank to flame arrestor. The pic I posted is engine on dyno and it is a temp hook up to vent can just to run on dyno.

Thanks Brian.

Anyone else have any input on what I'm up to here?

I appreciate any and all help and ideas.

Thanks, rob

I'm sure you will have several responses with different ideas of what works. There is usually always more than one way to accomplish something.The dry sump plumbing is pretty straight forward. A 4 stage pump will have 3 scavange sections and 1 pressure section. In most cases, a 4 stage pump is sufficient. The 3 scavange sections will go to the pan. I will have the pump set up with (3) #12 scavange lines and (1) #16 scavange return line to the tank. I run a small breather tank that is attached by a #12 hose to the dry sump tank. Any oil vapor leaving the dry sump tank will get caught in the breather tank.

Personally, we don't run any crankcase vacuum. I just vent the valve covers to the atmosphere. In a wet sump engine, the wrist pins are being oiled by splash lubrication. In a dry sump engine, you are pulling all of the oil back to the pan. If you have pistons oilers, then no problem. For that reason, a lot of dry sump engines will use piston oilers. They also have other benefits, like cooling the pistons. I don't want to pull any more oil away from the wrist pins than need be. But, that's me. I don't have any issues with running this way and have for years and years. Like I said, there is more than one way to get it done. Read the comments and do what you feel is best and suits your needs the best.
Eddie

Thanks for the reply Eddie.

The engine came with valve covers that are vented to the atmosphere and they have -4 AN oil feed lines feeding small internal manifolds that appear to oil the upper valvetrain.

I'll post a couple pics of the valve covers later.

Thanks again,
Rob

Here's a pic of the engine and you can see the filter assembly, the feed into the engine (looks like I'll be adding a cooler in this section of plumbing) and the -4 line going into the valve cover oiling manifold:
http://i205.photobucket.com/albums/b...ps2864915d.jpg

Here's a pic of the underside of the valve cover. Notice the discharge tubes are down by the gasket mating area. I would think the oiling would be to wash the springs but they are not directed that way? :
http://i205.photobucket.com/albums/b...ps7535408a.jpg

Here's a pic of the pan that came with the engine. Like I said earlier, I couldn't use it as it has no cutout for a conventional starter. Also, I would have needed a 6 stage pump for the pan to function as it's Completely segmented. Super cool scrap aluminum. Lol.:
http://i205.photobucket.com/albums/b...ps0501d140.jpg
http://i205.photobucket.com/albums/b...ps442d6cf8.jpg

Here's a better pic of the pump. I ordered new ORing to AN fittings from barnes and we took it apart for inspection and cleaning and it's in nice shape.:
http://i205.photobucket.com/albums/b...psfb7ce82d.jpg

Is dry sumping something that's generally left for higher HP applications? I am building a set of efi's (at some point lol) for my 38 and just wondered of I would see the benifits in an engine in the 500 HP range

While power does factor in, it's more about rpm than anything. However, the 2 do go hand in hand in a sense. In order to make more power, you usually need more rpm to do it (ie, larger cam). It's a little more involved than that but you get the picture. For example, you could have an 800 hp engine that should be dry sumped and 1000 hp that can stay wet sump. Let's say the 800 hp is similar to a Supercat engine....510 ci turning 7400 rpm. You would need to dry sump that engine. You would have a hard time controlling the windage (air) coming off of the crank. On the flip side, let's say you had a 598 with a 4.0L Whipple. It would be able to make 1000 hp at 5700 rpm, or less. There is no need to dry sump that engine.

Another thing to consider is power output. A consequence of horsepower is heat. The more power, the more heat that is rejected into the oil. In a wet sump setup, you can only have so much oil in the pan. It's get tough to control the slosh much over 14-15 qts. I did some pans in the past that were almost 18 qts. I played hell with them because once all of that oil starting moving around, it was impossible to control it. We had bulkheads and trap doors everywhere. It still sloshed all around and flooded the pan rails and leaked. With a dry sump setup, you can have as much as you want. We regularly use a 5 gallon tank. We run just over 4 gallons in the tank, but the lines, cooler, filter, etc, add up to another 4-5 qts. With the larger quantity of oil, it takes longer to heat it up and longer to contaminate it.
Eddie

Just to be clear.......I realize that dry sumping an engine with my intended use is overkill.
That said, the engine I bought is set up for dry sump oiling and it was easier (well, almost) for me to keep it that way.
I'll keep this thread updated as I build this system and hopefully the info will be useful to others.

Thanks to those who took the time and interest to reply.

Dangit ,I should have gotten me a dry sump system too.I'll put it on my christmas list. hf...

Tonight I was getting the engine ready to take to the machinist to start the process.
I started gathering all the odds and ends that would need cleaned/painted/annodized etc.... And was looking at these valve covers. I though it was strange that the discharge ports were down by the valve cover/head mating area. Upon closer inspection, the apparent discharge ports are tapped and plugged and there are two tiny discharge orafices on each side of each tube. They look to be engineered to wash the springs like I would have thought.

Pics:
http://i205.photobucket.com/albums/b...ps4bf06789.jpg
http://i205.photobucket.com/albums/b...pse7e748a5.jpg

Here's the filter assembly:
http://i205.photobucket.com/albums/b...ps39f47f1a.jpg
http://i205.photobucket.com/albums/b...pseed72fc1.jpg

did you buy an /oil tank yet?i have a peterson 3 gallon tank [used] from my drag boat days along with two complete systems that i will never need.

Hey mike. I haven't bought the tank yet.

7000 rpm :)

Vintage- I would change those filters and use Wix filters.

Cool thread- learned a lot!!!!

Got the pan painted and starting playing with the lines a bit:
http://i205.photobucket.com/albums/b...pssahnw4zv.jpg
http://i205.photobucket.com/albums/b...pswmfexj3l.jpg

Pan went on the engine last night. :coolcowboy:

Last look before pan:
http://i205.photobucket.com/albums/b...psmmosbj8c.jpg

Pan on the engine:
http://i205.photobucket.com/albums/b...psobfykoup.jpg

Also, just picked up this combo cooler and a KE thermostatic oil valve.

http://www.cpperformance.com/p-13617...il-cooler.aspx

I made a "mock up" of the stringer so we could articulate the oil pump and get a belt length and make sure the -16 return lines cleared the stringer:
http://i205.photobucket.com/albums/b...pseovsuhzf.jpg
http://i205.photobucket.com/albums/b...pshvpaoa0g.jpg
http://i205.photobucket.com/albums/b...pslmfaxrkn.jpg