Dry Sump for NSX (C30A)?

[Ponyboy]

Wish the NSX came w/ a dry sump from the factory. Not second guessing oiling reliability is reassuring.

Sheesh, gentlemen. Give the guy a break. Even w/o the obvious benefits of a dry sump, some people just like tinkering with their toys.

 

[scorp965]

The advantage isn't limited only to oil availability, there's also a power increase, since the engine's internal parts are no longer sloshing around in oil. With a multi-stage pump system, like the one pictured above, you can create a pressurized crank case, place the oil where you want it, and when it's done passing through the engine it's immediately sucked out of the sump, and into a reservoir. It's an advantage similar to a lightweight flywheel, but with greater impact.

Curious to see your results when everything's installed and running; are you just using the factory oil filter location for the oil supply, or are you engineering a solution for oil distribution?

Since the part is created in CAD, and you've test-fitted everything, do you have any plans to do a limited run of these pans, or is this a one-off for your car?

 

[Mark911]

So, does that actually bolt to the main caps somehow, or does it just fit against them VERY snugly?

Also, how did you modify the balacer/pulley assembly to drive the belt?

Lastly, care to quote a price for a copy? :biggrin:

The pan and main caps are shear pinned together, the stock main bolts fit just fine if you are so inclined but they use clearance hole sizes and therefore don’t carry any shear. The pulley shown is for fit check only as I made a novice mistake during machining of the stock pulley which resulted in less than desirable cross section area. Autowave provided me with a used pulley and I’ll correct that problem. In theory, I could perform the same mod to the ATI pulley but I’ll be adding a 6”dia 8mm pitch High Torque Tooth ring over the stock alternator drive to eliminate any slipping issues if I decide to put my old SC system back on. Paying $600 for a new ATI just so I can hack it up doesn’t make sense so I’ll stick with a modified stocker.

As far as making another system for sale, well that has to wait until after I’ve proven my design works. In truth, I only did this as a challenge to myself as a designer, engineer and machinist. I have all the tools, machines, software, skills and knowledge to perform end-to-end solutions like this so why not? I’m not expecting to see any measurable changes on the dyno, the stock windage system is plenty good for all but the most demanding dynamic conditions. But the stock pan, even with trick fences and “trap doors” can’t keep oil from piling up and getting whipped around by the crank during hard braking, cornering and acceleration (even if the pickup remains submerged). That’s where the drysump frees up torque or in the case of braking maintains positive oil pressure. You’d be surprised how many bearings get spun during sustained hard breaking or "shutdown" at the drag strip. This kind of performance increase can only be felt “on the track”.

In any case, it’s going to be awhile before I can test the system. After this project I’ll be faced with the decision to either re-design my SC system or build a turbo system. My rebuilt engine should be able to handle 500 – 600 hp so it might just boil down to cost now that I’m retired (at the ripe old age of 55).

 

[Mark911]

The advantage isn't limited only to oil availability, there's also a power increase, since the engine's internal parts are no longer sloshing around in oil. With a multi-stage pump system, like the one pictured above, you can create a pressurized crank case, place the oil where you want it, and when it's done passing through the engine it's immediately sucked out of the sump, and into a reservoir. It's an advantage similar to a lightweight flywheel, but with greater impact.

Curious to see your results when everything's installed and running; are you just using the factory oil filter location for the oil supply, or are you engineering a solution for oil distribution?

Since the part is created in CAD, and you've test-fitted everything, do you have any plans to do a limited run of these pans, or is this a one-off for your car?

I’ve already ditched the stock filter as I’ve added TWO oil coolers in an attempt to keep oil temps below 250 degrees. You can see my system in the “Thermal Control” tab on my website. In fact is I was barely able to obtain that goal at the end of a long track session. Adding more cooling capacity was getting to be a challenge from both a packaging and pressure drop standpoint. One advantage of the external pump is the ability to add coolers to the suction side of the system somewhere before the oil tank. This results in the shortest pressure side line lengths and lowest pressure drops. Now, typically oil from the suction side tends to be full of air and its thermal conductivity is less than desirable making the cooler(s) less efficient. However, my design leaves room for the Dailey pump mechanical air/oil separator and I’m confident that it will mitigate this issue and allow much more flexibility in the size and location of my oil coolers without the fear of excess pressure drops.

Yes, I have all the CAD models and CNC machine codes but without a 5 axis machine I still need to do quite a few setup changes and it takes time. With my spindle speeds (and a conservative approach) I’m able to do about 40 in/min feed rates with a ½ inch end mil. Even at pretty heavy chip removal rates it still takes hours and hours of machine time. I can only do runs of an hour or so at a time as I’m not comfortable starting the machine and walking away. That means many (probably over 50) sub programs and every new program has the potential of some little mistake that could ruin the part, some tooling, the machine or all of the above. Bottom line, it took LOTS of machine time. Obviously, now my code has been validated it should be faster but in hindsight I already have several design and producability improvements that’ll invalidate much of it.

I’m retired now and some supplemental income would be nice but someone would need to really want one (interpret as $$$s) for me to machine another. I think there’s more demand for a cheap (sub $5k) supercharger system and I think I’ve got the solution. Just need to find the time to develop it.

Mark

 

[scorp965]

I’m retired now and some supplemental income would be nice but someone would need to really want one (interpret as $$$s) for me to machine another. I think there’s more demand for a cheap (sub $5k) supercharger system and I think I’ve got the solution. Just need to find the time to develop it.

Mark, why not a well-packaged twin turbo solution, since you have a pressured oil supply? This was the goal when we explored dry sumps about a year ago, taking the platform to its extent, if you will.

Our designs never left Solidworks, so it's nice to see your efforts.

 

[Mark911]

Mark, why not a well-packaged twin turbo solution, since you have a pressured oil supply? This was the goal when we explored dry sumps about a year ago, taking the platform to its extent, if you will.

Our designs never left Solidworks, so it's nice to see your efforts.

Problem is I don't think a "well packaged" twin design is possible with the NSX, at least not without MAJOR rework of the engine compartment. SOS already has a fairly decent "bolt on" system at what I consider a reasonable cost. If I were to do it I'd figure out some way to mount both turbos in the engine compartment above the transaxle behind each cylinder bank feeding a custom plenum/intercooler dumping into individual throttle bodies. I've got a layout in my head but I need to scan the entire engine compartment so I can model it and my laser scanner is broken. If I happen to stumble on an extra $10k someday I might get it fixed. Mark

 

[sparky]

why do you what dry sump anyway?
I know it's good way to feed oil, but I heard dry sump is useless unless you'll be pulling lots of Gs all the time.

The biggest advantage of dry sump would be significantly lowered center of gravity.
Because the oil pan isn't there anymore, you can mount the engine whole a lot lower.
That's why a lot of Mazda Rotary enthusiast go for dry sump.

Otherwise don't do it. If you're doing dry sump just for "cool factor" then that's very pointless.

Having blown TWO engines in a 2002 Boxster S due to lack of a proper dry sump (plus taking long fast sweepers on a race track with sticky tyres) I can assure you it is can be a significant advantage. Although I do agree it's of little / no use for a street car. Interestingly Porsche advertised the Boxster engine as having an 'integrated dry sump' (marketing speak for the dry sump you get when you don't get a real dry sump)