OUTLAW EAGLE MANUFACTURING

herrhauptman · Joined: 28 Jan 2012 Posts: 17

Fellows, I need some answers here. I have a big block Chev, capable of 6000 with an A3. it has awesome oil pressure up until 5100. If I exceed that the oil pressure will start to drop off. I think the oil pump is pumping the sump out, and the oil is not returning fast enough. So, realistically the engine is limited to 5000 or less. Now, here are the things I have tried. A different oil pan, different oil pump, pickup tubes, distance from pickup to oil pan, adding extra oil, reducing vacuum, no vacuum, oil restricting lifters. I am at the point where I think the only solution to this is going to be a dry sump. Have any of you encountered this? This has never shown up on a dyno, and I think that is because dyno pulls are never that long. The engine is not mounted at a severe angle. Surely, someone has had the same thing happen. I am just asking before I spend another 5K (at least) to dry sump this thing.

picklefork · Posted: Sun Oct 04, 2015 9:38 am Post subject: Oil pressure issues

You don't mention what pan ( marine? capacity?) or oil pump you are using. HV? The only other thing is too much oil?

picklefork · Posted: Sun Oct 04, 2015 9:56 am Post subject: Oil pressure issues

Oil cooler? Oil temp?

herrhauptman · Joined: 28 Jan 2012 Posts: 17

I have always used hv oil pumps. I do run an oil cooler, and my oil temperature maintains 225-240 at high cruise speed (4000). As far as oil pans go, I have used a stock Corvette pan (LS6), a 12 qt Dooley, and a Moroso 7 qt. ( that is supposedly superior in controlling windage). I have tried overfilling by 1 qt. to see if that made any difference, and it doesn't.

boosted · Joined: 04 Jun 2009 Posts: 378

If you have too much oil in the oil pan you can run into a situation where you start to foam the oil. BBC are known for this. Usually you will see the oil temp be fairly high also. Try running it a couple liters low and see if it helps. BBC do not like airated oil also they have pretty high bearing speeds and they usually won't last long before turning a bearing.

picklefork · Posted: Mon Oct 05, 2015 9:47 am Post subject: Oil pressure issues

As boosted said too much oil can cause problems, I would use the Dooley pan. I have never seen a 12 qt Dooley pan, they are usually 10 or 14 qt. The 14 qt has kick outs on the bottom. I would think you probably have the 10 qt and I would only run 8 qts in the pan after the oil cooler and lines are full. Also you could probably use a bigger cooler if those are the temps you are getting at 4000, I would think that running 5100 or more would put you in to high oil temps

Brojax · Joined: 17 Apr 2014 Posts: 15 Location: USA

I had the same problem once. What the guys mentioned above is correct.. to much oil..If the pan is off you can take it and pour oil/Water in the pan until you have the right amount in the pan where the crank wont whip the oil. You can then mark the dipstick, or just keep track of how much you should put in it when you do a oil change. Then you will know the right amount every time. This should help your issues

rustyzipper · Joined: 08 Oct 2009 Posts: 67

I had this BBC in the BBFX race class several years ago. I had same issue at long sustained RPM runs, Oil pressure would drop off or bounce extremely. turned out is was a stock oil bypass valve opening and closing. forgot the part number but PACE performance has them for about $30 US. install new higher pressure bypass in the block. Wahlah...fixed oil pressure issue. I also had Tri Metal main and rod bearings which saved the motor during no pressure periods, note stock BBC bearings are junk...no lead or zinc....they are aluminum which will stick under stress/heat. Hope this helps.