Just got my new 406 running this weekend. Id like some feedback on if my oil pressure is OK.

Cold start at 1200 RPM, oil pressure is 60 psi.
When motor gets hot, the oil pressure drops to 20psi at 800 rpm, 40 at 2K, 45 at 2500, 50psi at 3,000. No metal found in first oil filter, engine runs well and has good power, no strange noises. Melling 54DS oil pump, 6.8 rods, ross pistons, FM4040M mains, Clevite 743H rods, brng clearances were .002".

thanks,

robertg

Just got my new 406 running this weekend. Id like some feedback on if my oil pressure is OK.

Cold start at 1200 RPM, oil pressure is 60 psi.
When motor gets hot, the oil pressure drops to 20psi at 800 rpm, 40 at 2K, 45 at 2500, 50psi at 3,000. No metal found in first oil filter, engine runs well and has good power, no strange noises. Melling 54DS oil pump, 6.8 rods, ross pistons, FM4040M mains, Clevite 743H rods, brng clearances were .002".

thanks,

robertg

Sounds ok to me...

Sounds good to me too http://forums.performanceyears.com/g...icon_smile.gif

What weight oil are you using?

Those are the numbers I get on my 455 and have had since I rebuilt it a few years ago. When I was rebuilding it, I noticed the lifter clearance in each bore was 0.002" which seemed high to me (you could feel the lifter rocking in the bore) but it was within Pontiac's spec (just). I wonder if the oil leakage past 16 sloppy lifters explains the pressure being somewhat low? Anyway, I don't worry about it.

Although I don't think you'll have a problem with those pressures, the hot numbers seem on the low side. You didn't say what oil- synthetic? What viscosity? Any out-of-the-ordinary lifter situation- rollers with no lifter-bore restrictor, etc.?

What weight oil would you use to bring the oil pressure up?

A switch from 10-30 to 15-40 or 20-50 will bring the pressure up but, how low is it and what is it covering up. Mine likes 10-40. 15+ at hot idle and 55 at cruise.

Thanks for the replies,

Using Castrol 10W30 and AC Delco filter. After 100 miles I'm going to cut that filter open and look for metal. If no metal found, I'll install a WIX filter and top the oil off, change in another 400 miles. Hopefully I'm being paranoid, this engine has crazy power and I want to enjoy it.

Thanks!

Chip,

Where is the oil pressure line tapped into, filter housing or next to distributor?

Next to distributor at oil galley. Gauge is an Equuis gauge I bought at O'Reilliys about 2 months ago. Should I bench-test with another gauge? Sometimes the pressure "flutters" like the relief spring is oscillating or something.

thnx

robertg

I get very similar pressures and I have the Eagle stroker kit in mine. I did run a second gauage at the oil filter housing to double check and it was approx. 8-10lbs higher. I think we should be OK. I will consider these pressures normal for my set up and if they drop outside my 'normal' range I'll have to address it.

sounds like a good idea. My 350 in the car previously had the gauge hooked to the filter housing. I'll try that as I have time. Keep the ideas coming, what else should I look for.

thanks!