Full Synthetic

5W30 synthetic is supposed to be worth 5 HP at like, 5000 RPM or something.

I never ran synthetices ever. Just gold old Castrol GTX 10W30... And I was fairly hard on the car, but just kept up on oil changes.

Shouldn't be any real power difference for the same viscosity oil. Go to the following, to see why.
http://www.carcraft.com/techarticles/15378/index.html
They tested different oils, and got more power with "thinner" oil, but also lower oil pressure. The people who make ONLY synthetics, like Amsoil and Royal Purple, are the ones who make the strongest claims for more power, etc.

Our cars were set up to run 10-30 from the factory even tho others were rated for 5-30.

Better be sure you have enuf oil pressure if you try 5-30 as it may be awfully low after a couple of blasts.

I think any quality oil is fine as long as you keep it cool and changed fairly often.

Synthetic will go higher before coking but our cars should not be coking oil if all is right.

What Steve said, exactly. If he got any smarter, they would make him post on "the other board".

I'll just add to the confusing topic of which oil is the best, by saying my favorite oil to use was Mobile1 20-50. I used it in a tired motor that saw lots of abuse. Blown head gaskets, water in oil, super knock, wasted turbos, lifting heads. The worst was when I made a pass at the track and the oil pickup tube fell off the block. I didn't realize I had zero oil pressure for about 20 minutes. No lie! I thought man my lifters sure seem loud all of a sudden!

One day I am going to tear this motor down and see what kind of super bearings or super crank is in this thing. Oil pressure was always right on the money. Did it live because of the oil? I don't know but that's how people come up with a favorite! headbang poon

Orlando_87GN:
I'll just add to the confusing topic of which oil is the best, by saying my favorite oil to use was Mobile1 20-50.

Click to expand...

I run Valvoline 20w50 dino oil in my car because it doesn't have an oil cooler... and the oil gets pretty runny after a few hundred miles of highway driving @ 2500-3000rpm, but this helps keep oil pressure up near 60psi at all times. I had 5w30 dino in there during the winter and thru the early part of the spring and the oil pressure was 5psi lower during/after long drives on the HWY.

I'd like to run a thinner oil, but I don't trust the oiling system in these engines. On the other hand, my MCSS' Chebbie 350 gets the lightest synthetic oil I can find wink

I still think the Buick leaks more oil.

does anyone run royal purple?

The Royal Purple Racing team runs mobil 1, its a rumor, but I heard it from sombody that would know.

Joe

oh well stick with the mobil one.. oh a old racing trick... mix half redline to half reg. oil its amazing the results