The oil pressure was in the 60psi range when idling on the lift. Drove it for maybe 10 miles under varying RPM's on the interstate and then exited. Coming to a stop light, the oil pressure dropped to maybe 20-25psi as the RPM's fell. Cruising pressure is +/-40psi. I'm trying to not run it higher than 5000RPM during break-in.

Engine is using a new Katech oil pump, new oil-pickup screen & o-ring, and 10W30 dyno oil for break-in. I only have about 20 miles on the motor at this time. I seem to recall seeing .001 stamped on the Clevite-H main bearings but I have a call in to the machine shop which clearanced the mains, and a message into Katech to see if their design would give me different oil pressure readings than the SLP ported unit it replaced.

There seems to be a lot opinions on minimum oil pressure. Some say 10psi per 1000RPM's is fine, but coming from always having ~40psi even at hot idle (and 50+ at WOT), it makes me nervous, especially on a fresh engine.

I planned to change the oil & filter after the test drive but ran out of time at the shop. So I guess I'll start there and see what happens. But if anyone has some constructive ideas, I'll listen

 

20-25 hot idle oil pressure is fine as long as it goes up with more rpm.

 

...and how much is appropriate for WOT? The rev limiter will be at least 7200, maybe 7500, if that matters.

 

I have the same concern on my new rebuild. Spent a week with a mechanical gauge strap tied to a wiper arm and found the lowest my pressure ever was was about 18 psi on an extremely warm day.. Pressure responds well to rpm increases, (40 psi at 2k) so I'm not as concerned as I was before..


link to my previous post:
http://web.camaross.com/forums/showthread.php?t=535642

 

Oil pressure sounds good to me.

What kind of engine is this that needs to be spun to 7200-7500 rpm on an LS6 intake manifold?

I can't think of anything that would require that unless you're going with a huge cam (low 250s-260s duration @ .050") and stock cubes.

Mike

 

I would try to stay under 80psi max for oil pressure.

 

I know the LS6 intake manifold will restrict peak power to around 6300RPM, but I want my shift points to take advantage of mechanical gearing. I won't know what I'll set my RPM limit to be until I can get it on a dyno. But I built the valvetrain to accept a 7500RPM limit.

 

Mine is 25-35psi at idle depending on temperature outside, WOT 50-60psi and cruising speed is about 40psi i wouldn't worry about it too much just keep an eye on your oil level.

 

I'm starting to relax on the oil pressure. I wonder if the Caddy lifters affect the oil pressure as a result of the internal changes?

http://speedtalk.com/forum/viewtopic...w+oil+pressure

http://speedtalk.com/forum/viewtopic...essure&start=0

http://speedtalk.com/forum/viewtopic...t=oil+pressure

 

I found an old post which indicates Katech stopped shimming their oil pumps for higher pressure...

http://www.ls1tech.com/forums/showthread.php?t=67432

And another post with a Katech exhibiting the same oil pressures I have...

http://www.ls1tech.com/forums/showthread.php?t=251796

Not that I really want to take apart the oil pump, but I wonder if my old SLP ported pump has a shim in it which is the correct size.

 

Most 23x/23x duation hydraulic roller cams make peak power around 6000-6200 rpm on a 346/347ci motor.

If you went with a bigger high 230s/low 240s cam, you can expect to make peak power around 6200-6400.

There's absolutely no reason you should ever shift a motor 1000 rpm over the peak. You'll probably be making 50 less rear-wheel horsepower at 7000 rpm than you do at 6500.

 

I'm including the tranny and final drive ratios. Will I accelerate harder with the numerically higher gear even with the power dropping in the next 1000 RPM's vs. a numerically lower gear after shifting? Why would you shift early if you continued making more force at the wheels without shifting?

 

Nope. You simply gear your car for its intended use and shift from there. If you're running the 1/4 mile at 130 with a 4.10 gear @ 7000 rpm with a 7200 rpm redline or running it at 130 with a 3.73 gear @ 6500 rpm with a 6800 rpm redline, then what's the difference if you're still making peak power at 6300?

The only difference that I can see is that 7000-7200 rpm will kill your motor faster, but not make any difference in your times.

 

Then build the motor correctly The difference is after you shift. The 1000RPM between, say 6200 and 7200, combined with driveline gearing may give better acceleration during those 1000RPM's than shifting into 2nd gear due to the gearing advantage. Google 'optimal shift points'.

 

My motor peaks at around 6200 rpm, but I've taken it to 7200 rpm. Did I go faster when I shifted it at 7200 than when I shifted it at 6500? Nope....but then again... I digress....maybe I should base my experience on Google.