Originally Posted by TomZ

So yesterday I was chasing a ignition issue that required me to do some rewiring. I did not get the engine started (my module might be gone because it got wet), but I noticed while cranking that the oil pressure was coming up strong on the gauge (25 psi on a slow crank... tired batteries). This was not the case before (the gauge would not move until running), and would lead me to believe that the filter was probably the issue. We'll see next weekend when I play with it some, but this is a positive change. I have yet to cut into the other oil filter, but the oil that came out of it was clean (though somewhat dark from assembly lubes). If I have time tonight, I'll open it up.

Clearances on this build:

Mains are .00275 with #5 at .003
Rods are .0023

The general thinking here is that these clearances may be tight, but I've built them similar with no issues. So long as pressure and oil temp are good, it should live just fine. We'll see.

Regarding oil pressure being 79 psi... I was quoting the exact number per its readout on my dyno paperwork. Let's call it 80 psi from here on.

Originally Posted by mike tkach

tom,i only pointed out the 79 pound thing so people could see what kind of pressure it made without the merc oiling accessories,i was not being a wize guy.just wanted to make sure you did not think i was being a dikkhead.edit in,15w40 would be the correct oil to run with those clearances imo.

Originally Posted by TomZ

Just an update...

Got the batteries charged up and changed plugs (fuel fouled from dealing with the wet ignition). Fired right up and we have about 70 lbs on the gauge on cold start with 50-55 lbs at warm idle. Revving the engine some on the hose bumps the pressure up into the 65-70 lbs range.

I would say that the POS AC Delco filter was to blame for the funky pressure. The pressure on the gauge wouldn't even move much no matter how much it was revved.

Sticking with my K&N filters from here on!

Thanks for all the help everyone! -Tom