Oil Weight ?'s

What are the pro's and con's of running a heavier weight oil, and what dictates when it would be necessary? I have used 20-50 and now my motor is good and broken in the oil pressure is not what it used to be. Idling hot it sets about 20psi and goes back up with rpm increase. I put some 50wt in today to try. I was thinking now that things are worn in and the d&d headders putting a primary right on the oil pan on both sides a heavier wt should be ok when its hot and the oil is warm. Cold pressure would set at 55psi and on warm days and when the motor reaches 170 to 180 and the oil thins it drops.

When the motor was first built I could idle at 190 and still have about 60psi

sounds like time for a fresh up on the motor , rod& main bearing anyways and a new oil pump , before it goes knocky, knock - bang
Frank
It's easier to fix before it goes bang

TN Bullit, I would like to make a few comments relative your post, if I may. First of all I'm not the person who can tell you what direction you should take concerning oil. There are many people on the www.429-460.com website that are much more experienced about oil. I do however believe that an engine's design (bearing oil clearance) should be a consideration as to the type and weight of oil to be used, not an after thought! Tight bearing oil clearances may like a light oil and visa versa with loose bearing oil clearances may like a heavier oil. I suppose the "general idea" of bearing oil clearance of .001" per 1.0" journal diameter is a good starting point. Synthetic vs. petroleum (oil) may be a factor as to bearing oil clearance. I suppose a heavier weight oil may have a place in an engine application that is operated at a upper level of engine speed over extended periods, if bearing oil clearances are toward the "loose side". If elevated oil temperature exist, my preference would be an oil cooler instead of heavier oil. I think I can be safe stating heavier oil taxes the engine components of different areas and may cause poor service in those areas if not failure. To make a long story short, if you take Frank's advise, think about oil and bearing oil clearance in the same sentence!

Just more bullsh*t,
Dave.

the wife' getting tired of heating the oil on the stove in the motorhome between rounds to keep the oil pressure down !!! LOL sick but true in the early spring and the late fall meets!!
Frank

I have wide clearences on the motor. The motor has mabe 20 passes since I built it last year. Has street miles to. When I changed my cam over the winter, everything checked out good so I put it back together. I see what you saying about the cooler and might call Lem to see what he can get me.

Something doesent sound right my pressure stayed the same after 2 seasons of bracket racing ?

Did you change the cam bearing to you could be loosing some in thew cam bearings