Dry Sumping Motors
 

Dean or anybody what are the advantages of Dry Sumping Motors. I have a 36 Skater with Quad Whipple Motors Dynoed at 1025 HP at 6,200 RPM. Winter Project could be Dry Sumping and or Changing from Twin Small Whipples to one large Whipple. Trying to get a little bit more HP without running more than a 1/4 Race Fuel Mixture and still maintaining some reliability. What are the advantages and disadvantages of Dry Sumping? I know Drysump motors create more vacum so less Oil spillage but will it also pick up some HP.

Drysump should give arround 30-35 HP more. But alot of work.
Complette engine has to come apart , need to close some oiling holes in the block and sofort.

The engine does not need to come apart to change it to dry sump. First, you need to change the oil pan and remove the stock oil pump and rod. You will need to buy a dry sump pump and tank. For your engine, I would recommend a 4 stage pump. It has 3 scavange sections and 1 pressure section. Your current oil filter and oil thermostat should work fine. You will also need a mandrel on the front of the crank to drive the oil pump and a belt. It does require quite a bit more plumbing, since you have all the scavange lines going to the pump and then on to the tank.
It will increase some power by not having the crank spinning in oil. As soon as the oil hits the pan, it is sucked out. It will also help with oil temp since the oil is stored in a remote tank and not in the engine. You also don't have an issue with leaks, since there isn't any oil in the engine. You have less of a chance of the pump sucking air and less of a chance of windage from the crank digging a hole in the oil in the pan. You will get a better, more steady supply of oil.
It is a costly conversion, but well worth the money. You are on the borderline of needing it IMO. You could get away without it, but it would be a worthwhile addition.
One other thing, you should not need to run any race gas (even 25%) with 1025 hp and a Quadrotor. I regularly make 1200 hp with a 2.3L Quadrotor on pump gas with a hydraulic roller camshaft. There are other builders doing similar builds with similar results. I do a LOT of Whipples, so I'm pretty familiar with them. You may want to verify the need for the race gas with the builder to see if it is nesseccary. You may be wasting money buying that fuel. Give me a shout if you have any questions or if I can help you in any way. I can also do the conversion to a 5 liter Whipple if you are interested. Thanks, Eddie.

Eddie, sorry thats just what i heard.
But dont you need to block someting up in the motor ?????
Because when you wetsump a supercat you need to open something in the block ?!:cool:

Hi Eddie,

What are your thoughts on using a 5 stage pump,closing the valve covers and pulling 10" or more vacuum ???

Cat,
I think we have had this conversation, but I am too old to remember! My experience is a vacuum set-up in a boat is a plus as the bilge stays much cleaner. We experienced minor HP gains on the dyno at 10-15 in of vacuum with std tension oil rings.
Does your current dry sump set up produce any vacuum at idle?
Ben

We build several hundred marine dry sump pans and tanks a year at Stef's. I see your on the West Coast, REX Marine is stocking dealer for us and and DNE also is a WD for our stuff. As mentioned the retro fit is not to complicated except for mounting tanks and new plumbing along with the oil pump mount. Our offshore tanks are 2.5 gallons of oil and we have the prints for several Skater mounts. Pan wise I might suggest going to a divider pan and going 5 stages. The pan would have 4 compartments sectioning off each with its own pickup. This style of pan we have seen on engine applications promotes very good ring seal and is worth a few HP. Pans are available in steel, stainless steel, and aluminum.

You do have to block off the rear main cap, where the old oil pump was. If you don't you will not have any oil pressure.

You don't have to block off where the pump was in the rear main cap if you use your same oil adapter. You will only be putting oil into the block, and not back into the main cap. They are 2 seperate passages. They also make an oil filter adapter that only has one fitting and covers the entire area where the stock filter would go. If you use that one, you will need to block off the rear main where the stock pump goes since you are pressurizing both passages. I use a standard oil filter adapter with 2 fittings(1 in and 1 out). I just put a plug in the one labeled OUT and only use the IN. The oil leaves the tank, goes thru the pump, filter and cooler and then to the IN fitting in the adapter as if you had a stock pump in the pan.
You could use a 5 stage pump if you wish. I would close off the oval shaped holes above the camshaft and put a pickup/strainer in the lifter valley to scavenge the oil from the top end. You can then put a bulkhead fitting in the china wall at the back of the block to run the oil back to the pump. This stops any oil from running past the cam and onto the crank, thus robbing horsepower. If you did that, I highly recommend pistons oilers. You will no longer get any splash lubrication from the oil draining down from the top end.
I would then put 3 scavange lines in the pan and the 5th is the pressure section. Hope this helps, Eddie.

Ben,We know you are at that young tender age where memory doesn't fail ! Yes, I also recall you and I talking about our 5 stage,sealed system pulling vacuum. However,it seemed interesting to hear Eddies comments. Also,I'm curious why more is not said about closing the valve covers and pulling vacuum.

We are pulling 11" at 5,000 and above...the vacuum decreases as rpm decreases,until positive pressure occurs at approximately 1,500 rpm and increases as rpm continues to decrease. However,the flapper valves open as positive pressure starts to occur,thus protecting the seals. The flapper valves would also open in the event of a piston burning.

We also find a fringe benefit at idle. In summary,the system idles well.

Incidently,the pan,tank and pumps come from Stef...good stuff.(The tank is square--4 gal.) The pulley ratio should be sized for volume of oil consumed. For example,we have piston sprayers,lifter sprayers,valve spring sprayers,honed push rods, HP6 filters and dash 12 lines w/nascar screens.