mark944turbo

As an alternative to dry sumping, I am trying to design a new oil pan for my car. It will be for track only and produce 4-500 hp.

The problems with the current pan that I am trying to solve are that the baffleing is insufficient (the pickup still sucks air when going over a hill, braking, or turning) and that the crankshaft sloshes the oil around and causes too much air to be mixed in.

I would like to use the stock pan as a start, and just weld in the modifications.

I have some ideas including an air oil separator, baffles, and trap doors, but if anyone has considered this idea before I would appretiate any discoveries you have made.

My goal is to increase oil capacity, eliminate air and oil mixture, and solve the bearing failure problem.

adrial

Actually Milledge (IIRC) believes that the oiling issues come from the oil pump being spun faster than designed and causing air bubbles in the oil (in addition to baffling issues).

mark944turbo

Well, without costly dry sumping there is no way to avoid that problem. Im just trying to do my best on a budget.

adrial

You may want to check out the Lindsey Racing oil pan baffle kit. (It's a weld in baffle).

turbite

In addition to the weld-in baffle.
Also theres crossdrilling your crank (this won't help anything but the bearings obviously
Also modifying the pickup tube screen with a band around the outside so it doesnt pick up from the sides.
Accusump maybe?

All are options, depending on who you talk to some are a waste of money, others arent.
edit: 4-500 hp is a bit much for an oil pan.

hosrom_951

Cross drilling the crank and rods are an expensive way. To help, an economic way, the Lindsey Oil Pand Baffle it looks good, you get the door flaps and a modification for the oil pick up tube.

David Floyd

Can someone tell me a little more about the pick up mod ? I am having a flapper door welded in now and I could modify the pick up now also.

The crank is already crossdrilled and knifed.

turbite

Its just a band that goes around the outside of the screen pickup.
As it is, the pickup can get oil from the sides, so under hard cornering, it can pickup air from the sides.
Getting the little band tack welded on there supposedly prevents this.

I havent seen one in person, but I plan on doing it.

951 S

I did a bunch of research after blowing 2 #2 rod bearings at the track. As Adrail said these motors create alot of bubbles or foaming in the oil under racing conditions. Dwyane at Koklen expalined that alot of the rod bearing failure is due to the foaming and small part of it was the pan and pick up design. The airing of the oil does not help the bearing to rod clearance The best way to solve this problem is to run an oil and air seperator, much like a turbine jet engine uses. I was told that Millage is a strong beleiver in this theroy also. The seperator is not cheap ($1,000) but it beats rebuilding another motor. Powerhaus also sells a pan and pick-up mod for about $300.00.......

David Floyd

Can you direct me to a site with info ?

M758

Do a search on rod bearings and you will find lots of theories and little concrete evidence. I believe that short of a dry sump all you can do is attempt to minimize the problem, but can't prevent it entirely. Thinks like baffled oil plans help, but cannot prevent. After doing some research I don't think that cross drilling helps one bit. I have looked at the oil flow paths from the main bearings to the rods and believe this in earnest. That said there are lots of small things that can be done.

For example
1) Engine RPM .. .Keep to a max of 6500 or so. More RPM's mean more heat and greater chance for frothing.

2) Make sure you don't run low on oil. Run at the full mark to just a tiny bit over for each session. Just don't run too much over since that makes the frothing problem worse

3) Keep the oil cool. Cooler oil will provide better protection at the rod bearings and oil coolers are important in doing this

4) Run a high quality racing oil like Redline or Amsoil in a 20w50 or similar thick grade. Mobil 1 actully tends to thin under racing conditions and loose oil pressure. I rum Amsoil Series 2000 20w50 and it maintians oil pressure even without an external oil cooler (stock NA motor) when Mobil 1 would loose pressure over time on the track.

5) Keep you Rod bearings AND main bearings fresh. Worn bearigns will leak more oil thus take a greater volume of oil maintain proper operation. This applies to rod bearings and mains since the oil source for the rods is the main bearings. Even through the main bearings would fail first larger clearance mean lots of oil leakage and thus less oil get pumped to the rods. Thus the rods can go boom. I have seen a few engine spin brand new rod bearings when the mains were old and had not been replaced.

6) Keep the balance shafts and ensure they are timed right. I had a rod bearing spin on me any cause a large hole to develop in the side of my block. I still can't confirm it be I am believeing more and more that it happened when my oil pick-up tube cracked due to mis timed balance shafts. The cracked tubed sucked air and boom.

7) Oil pan baffling can help to ensure that the oil pickup is cover when on the track durign cornering. You don't want the oil pick up to suck air.

8) I guess air/oil sperators can work, but have heard of failues even with them. So like everything else on this list don't count on it alone.

Sam Lin

Mark, have you looked into an Accusump? It'll achieve all your goals for less hassle and less cost. Pair it with something like Lindsey's pickup mod and call it a day.

Sam

turbinek

My guess is Porsche knows the facts but wont' tell. Guess why...
P.S. Last weekend took 24h at Nürburgring place "Grüne Hölle"
a 700 hp Porsche turbo would not reach chequered flag
engine failure.
Frank

951 S

David, the site is kokeln.com. I really beleive in this product and so do many on the top 944 engine builders. Yes you can put in new rod bearings every year $$$ to keep a motor from blowing at the track. According to Kokeln there are many 300+ HP motors they have built running the air/oil seperator with no rod failures after 3 years of track events. M758, I agree with alot you have to say but if there was no oiling problem with these motors then why would the rod bearings have to be replaced so much more often then other Porsche motors? There is little concrete evidence from your average consumer, but check with the major engine builders R&Ding for some answers.

Duke

Any more info about Accusump?