Blown Alcohol Oil & Windage Control ???'s

A lot of the oil pans that I see for blown alcohol motors are pretty simple in terms of being small'ish in volume and no significant right side kick-out, whether wet or dry. Is there much to be gained from taking some design ideas from the Pro Stock guys?

For example, big kick-out, big volume, crank oil scraper, knife edging, super polish or oil shedding coatings, vacuum pump, over sized scavenge pump, compartment bulkhead walls up to under each main cap, coated bearings, etc..... ?

This would be for an engine spun well in excess of 10K rpm on a routine basis.

Or in the big scheme of things is the benefit to be had tiny in terms of the overall power being produced? Just curious as to people's thoughts or findings.

 

170 views but no thoughts ?...... I guess the gains must be pretty small then.

 

I read somewhere once that top fuel engines actually ran the cranks partially submerged in oil to help quell some of the harmonics inside the running engine .i would think that a hemi pumps so much oil up top that windage is not much of an issue.

 

I have seen some blown alky engines with vacuum pumps. Some people swear that they are worth something, others not so much. The vacuum pump was designed for a normally aspirated engine with no appreciable cylinder pressure. I would be concerned with a larger net pressure difference between the bottom side of the piston and the top side, but that's me. The bearings dont stay in the engine long enough to get your moneys worth with the coatings and if you have the proper bearing with the proper clearances you shouldnt be having any issues to begin with. Windage trays would get into the way of checking your bearings, plus most of the wetsump pans have some sort of crank scraper deal built into them. As for baffles, bulkheads, etc they are there mostly for acceleration/deceleration to prevent the oil from running away from the pickup in either situation. The kick out in a wetsump deal might be worth something as oil likes to congregate in the passenger side, which would be where oil would sling if it was caught on the crankshaft. Dry sump systems have an advantage in a funny car or door car because you can run a larger volume of oil due to ground clearance issues. Again, I wouldn't run a two stage dry sump pump off the stock Hemi location, but that's just me. A true dry sump could possibly have an advantage in the weight department (oil volume) because you can scavenge from enough areas that you wouldn't need 12 or 14 quarts to cover you for the 1/4 mile. In summary, our engines get so hot and with the oil being diluted with alky, it doesn't much matter what you do with the oil control as long as there is enough to maintain oil pressure for 1320 feet.

 

Hopefully I can shed some light on some of your questions. I have delt with the oiling systems of both Top Fuel and Blown alcohol and both NHRA & IHRA pro-stocks for a while. Obviously Moroso builds oil pans and oiling systems along with vacuum systems for both.

So to answer the question on vacuum pumps:
A long time ago we came up with the #22643 Pro-Mod vacuum pump and installed it on two blown Pro-mods, one a nationally known car and the second a local, but top 15 in the country car. Both racers said they saw a mph gain, and was happy with the way the oil looked after the vacuum pump would pull a majority of the methanol out of the oil. Once the alcohol becomes a vapor, the pump pulls it out before it recondences and turns backing to a liquid.
The down fall was the extra plmbing, check valves, and another parts to run off the front of the engine with a special drive mandrel. You still have to run the burn down tubes, but need inline check valves to pull vacuum. And you need to pull vacuum from both valve covers..period! So theres a gain, but to much stuff and effort. I can set up someones car with it, and have had interest, but no one has pulled the trigger. NHRA has made "vacuum pump and evacuation devices" illegal in TAD & TAFC. Thats another story for another time.

Kicked out oil pans and windage control:
If you wanted to "follow the lead" of pro stock tecnology, the first thing you would do is cut the block shirt out of both sides of a Hemi block, and them would have to machine and build a special rail that would accept a two piece oil pan. Its been done, and cost a lot of maney and is justified on a pro stock engine. If you notice now, they dont run that HEMI block in pro stock anymore because of this reason. The old Buick V-6 oval track engines did this to hundreds of them and ran a "L" shaped oil pan. Again, way to much work and a loss of bottom end strength to make it worth it.

The windage control is nearly impossiable to make as good as a standard cap level block. The biggest issue is the balance in how much oil goes to the top of the engine versus gets back to the oil pan. There many different ways its done. The way certain teams want things and do things is different than others. Ive had windgae tray designs work well for some and not for others. When you buy our product, we have much of work in our production pan. we are always willing to build what you want though.

True dry-sumps are multiple pick-ups, and I have worked with one team that went from a standard Pluguer pump to a 6 stage dry-sump pump. It went having 18 quarts in the system to 12. Worked well when it was happy. But once again, alot of plumbing, and stuff that makes the possiablity of something being left loose or breaking not worth it. Oil life increased a bunch, and its easier to control engine heat. The multiple stage pumps get tore up pretty good when junk goes through them, and its not a cheap endevor to fix that all the time.


The coated bearings work well, but in so many cases the journals are so big and the clearance is great, the coating is beneficial, but for different reasons.

On the wet sump oiling systems, the extra oil thrown around the system pulls heat off the rods and such, so the windage is an aid. I had one season where everyone had us build smaller volume oil pans for weight reduction. 10 races in to the season I had all those teams ask for the bigger pans back because they all where throwing rods out and said that the less oil in the system was not getting the heat of the parts and causing failures.

Thats about all I have to contribute to your questions. I hope I have explained some of what you wanted to know.

Scott Hall
Sales Engineer
Moroso Performance
TAD 115A

 

Thanks for the replies. Very informative !