Oil pressure question

[MAURICE BLENDHEIM]

Ron… X2 on taking oil pressure from the front of the engine. Oil pressure reading will be after all internal leakage. MB

[Ron Gusack]

The pressure is about 50 at 2500 against the converter, goes up to 55ish on launch, then drops to low 40's for the rest of the run. After the stripe it climbs up a little. I put a gopro in it for one pass a couple weeks ago.

I've taken it from the #1 main before, is that good enough or is it better to get from the end of that galley? Is -4 braided what most use?

The last race of the 2017 season I over reved it bad on one run and I'm waiting for the analysis from that oil now. I hit 8400 in 1st gear and somehow it stayed together. Maybe this analysis will paint a different picture.

[Mike Pearson]

Ron,
I have been running a Moroso Billet pump in my 350. I had one of the Melling pumps break off and kill the engine. No more Melling pumps for me. Could be an issue with the pump. The billet pump does not have a standard pick up. it pulls the oil right from the bottom of the pump.

[bry-war]

Originally Posted by Mike Pearson

Ron,
I have been running a Moroso Billet pump in my 350. I had one of the Melling pumps break off and kill the engine. No more Melling pumps for me. Could be an issue with the pump. The billet pump does not have a standard pick up. it pulls the oil right from the bottom of the pump.

Order up rebuild parts for your moroso billet pump and you will get melling parts.

BW

[HP HUNTER]

Type of cam bearings? BBC - you have to pay very close attention to cam to cam bearing clearance, at least that's what I've found. When you drop pressure on a run its usually a windage issue, type of pan and amount of oil?

[Ed Wright]

Originally Posted by HP HUNTER

Type of cam bearings? BBC - you have to pay very close attention to cam to cam bearing clearance, at least that's what I've found. When you drop pressure on a run its usually a windage issue, type of pan and amount of oil?

I was thinking amount of oil. Or, drain back issue. Returns blocked off? Personally, I would try adding a quart.

[CMcAllister]

I like -3 for pressure gauges. It's more responsive than -4 due to the reduced volume in the line. If using a Racepak, why not go total electric and use a transducer?

[Ron Gusack]

[QUOTE=Ed Wright;569241]I was thinking amount of oil. Or, drain back issue. Returns blocked off? Personally, I would try adding a quart.[/QUOTE
My last oil analysis was the last 26 runs from 2017 and that oil sat in the car over the 2017 winter. I forgot to send it in until a few weeks ago and when I got it back it showed 5% fuel dilution. My only explanation for that is a couple start ups in pretty cold weather over the winter with no choke and a very lean idle circuit. I just sent in a sample for the first 31 runs this year and if the dilution numbers are still bad I'm thinking that could be the issue.

The oil is fresh now and if pressure doesn't improve, I'll add a quart and see what happens.

[Ron Gusack]

Originally Posted by HP HUNTER

Type of cam bearings? BBC - you have to pay very close attention to cam to cam bearing clearance, at least that's what I've found. When you drop pressure on a run its usually a windage issue, type of pan and amount of oil?

Cam bearings are King's but I don't know part number. The pan is a 7 quart Moroso which is basically a stock pan with a deeper sump, nothing special. I run 6 quarts of Penn 10-30. It's possible that I have the pickup to close to the pan. I recently read a post that said it should be about 1/2" and I've always put mine at 1/4 to 3/8.

[HP HUNTER]

Originally Posted by Ron Gusack

Cam bearings are King's but I don't know part number. The pan is a 7 quart Moroso which is basically a stock pan with a deeper sump, nothing special. I run 6 quarts of Penn 10-30. It's possible that I have the pickup to close to the pan. I recently read a post that said it should be about 1/2" and I've always put mine at 1/4 to 3/8.

I run the pick up .310 off the bottom of the pan. I use coated Durabond cam bearings. The Durabond CH12 bearings go oval, never use these, especially if clearance isn't maintained. 6 quarts is fine if there's no excessive leaks. What is inside your pan?