Aluminum Oil Pan Info and designs
 

Hey Guys,

I would like to add a bit more oil capacity in my 12a as I track it a fair bit to keep oil temps cooler and also add a baffle system. I have seen a few trick design for the oil baffle with hinged doors and I think this might be the way that I'll be going.

What are your thoughts on that? Also thickness of aluminum should I be using as the flange, and what grade of aluminum is best suited for this application. Also any tips to keep the flange as straight as possible while welding besides just clamping it a much as possible.

At the rate that I'm going at, everything on my car is going to be one of lol. As long as I try to keep it a bolt on matter it might not be too bad if i break down far away from home.

Will you be trying to bend the aluminum? If you have a break, I would suggest 5056 or 3003 in their standard hardnesses (I can't remember what they are off teh top of my head).

If you aren't going to be bending them; that is, at every point you have a break line you'll be welding it, then I would suggest 6061-t6. It its more stiff than the other two, and I feel it is easier to weld.

1/8" will be the easiest to weld. If you're really good, you can try 0.063" aluminum, but you may have problems with warpage and over penetration. Perhaps try making the flange out of 1/8" and the rest out of 0.063. It really depends on if you are trying to save weight or not. If you're not concerned with weight, then use 1/8". Something to think about is whether you'll have more heat rejection with a thicker or thinner pan.

As far as tricks, an oil pan seems to be fairly easy as all the welds occur at angled sections and along edges, which usually doesnt cause noticable warpage. Where I have always noticed problems is when you are trying to weld into the middle of a flat panel, not along an edge.

I made this for a Nova with a 13b-re. The outside is made of 3/16" due to the fact that there is only about 3.5" of ground clearance when the car is dropped down, so I wanted it to be hella stout. The flange was waterjetted out of 3/8". I would build a backing plate jig out of 1/4" - 3/8" steel. Without it, the pan will definitely warp. But, that means you will have to drill the oil pan holes first. As I'm sure you know, after welding the aluminum will shrink and your bolt holes might not line up correctly anymore (ask me how I know). To keep this from happening, drill the holes in the pan and jig so the bolts fit snugly. You'll have to tap them out after welding. Preheating will also help with the warping and shrinkage.

I think 1/4" on the flange would be the absolute minimum thickness.

Make sure to post pics when you're done.

If i were to do it, it would probably look like what 13brenova did with his. I remember seeing your thread somewhere with those hinges and really liked that idea so I might copy it. So 6061 i guess would be what I'll be doing.

Now if I were to have the flange laser cut, out of 3/8" aluminum, and bolt every hole on to a table top or something, do you think when i try to take it out it would be tensioned and hard to still put in?

Another thing that I have to keep in mind is budget. I'd like to keep it under 200$, do you guys think that will be doable with laser cutting all the pieces?

It will still shrink a little, but should be good. I'd lazer cut the holes to fit the bolts very snuggly, and then when you are done welding, drill the holes a tiny bit larger to ensure everything fits nicely. $200 will be very hard to do unless you find some free material or lazer cutting. 3/8" aluminum plate is a bit pricey.

Sam, if you're trying to keep it budget, why not just use mild steel? Won't be as light or reject as much heat but it will meet every other requirement. And shouldn't warp as violently as AL will.

what would it cost roughly to get it made? I know cutting that 3/8" piece is going to be a pretty penny, I had an intake spacer cut out of 1/2" thick material and that was getting close to 100$ by itself. Unless I grab a piece and cnc machine it myself.

I could go the mild steel way if it came down to it, but i would rather have it out of aluminum.

Also here's actually a good question, how good do you think it will hold up to the elements. I drive my car all the time (rain, snow or shine) so the effect of salts and what not at it.

My pineapple pan has not been engatively affected by the elements in three years. Although I would change alot of things about it - weather has done little to it. It is coated though with what they call "wrinkle finish" I.e some urethane texture spray.

I'd say it would hole up fine though. As fine as any other aluminum piece on the engine.

What are some things that you would change to the pan you have?

-Thicker mounting flange (believe its 3/8).
-Less corners on the o-ring (less leaky. It'll leak on 2 out of 3 installs....actually seep more so then leak...)
-Real drainplugs instead of stupid tiny allen key heads on massive bolts. Had to weld 14mm nuts onto them after about my 4th oil change because the allen key hex's were stripping. EDIT: In all fairness they *may* have been OK but when I did the first oil change I nearly stripped them right then and there because it came from pineapple with about 6000ft/lbs of TQ on them.
-Add temp sending unit boss and fluid level boss.

Overall happy with it though, the baffling and windage tray are great. Just I'd go a little further with the whole design if I were making one myself. And I'd likely do steel since I am not a very good AL welder.

Why would you want the flange to be thicker than that?

As for welding aluminum I'm not too shabby with that. I've started welding a gas tank out of aluminum out of 0.049" thick aluminum. It's half done right now and with no leaks. I would of been easier to weld if those guys bent the whole thing on a break as oppose to pliers and a hammer.

I tried to order a gasket through Mazda to take measurements from, and they wanted about 80$ for it! Outrageous I tell you! An aftermarket one is about 15$.

.

dj55b,

If you're going with a thicker flange or a deeper oil pan, I also recommend extending the oil pickup line. For example, if the sump is 1 inch deeper than stock, extend the oil pickup line so that it scavenges oil 1 inch lower than stock. That way the extra oil will actually be used to cool the motor because that extra quart will get circulated with the rest of the oil instead of just sitting out of reach at the bottom of the sump.

If you're tracking your car, oil coolers add even more total circulating oil, in addition to cooling all the oil in the system. Then there's a vented hood, larger radiator, ducting....

If I were doing it I'd go with:


- .500" 6061 flange with sealant groove. Rotary oil pans love to leak. The thicker flange and groove will help prevent this.
- 0.125 5052 aluminum for the walls. Cheaper then 6061 and corrosion resistant, used mostly for marine stuff. Can be a bit difficult to machine depending on temper. Also bends nicely.
- 0.25 5052 for the bottom with 0.125" grooves in it to increase surface area and cooling.
- 0.500 thick weld in flange for drain plug.

To prevent warpage I'd bolt it down well before welding, and then lap/surface it afterwards.

I will finally be taking out that beehive cooler on my car and swapping in a second gen FMOC in there. All lines will be -8AN braided lines.

Good note on the oil pickup line. That just unbolts from the bottom of the engine correct?

As for putting groves on the bottom of the pan, I have thought about that. I could still also consider making the whole thing out of a billet chunk. Not sure how much a chunk of aluminum like that would cost.

That extra quart will be circulated anyway, there's a ton of mixing going on in there from acceleration in all 4 directions to the constant flow-through of oil from the engine and back through. Pickup from the bottom is good anyway.