I use 20w50, but that's what my engine builder told me to use.

 

I did a bunch of back to back oil tests a couple of years ago and found that the light weight synthetics were always faster.
In my new Top Stock LT4 I will be running 3.5 quarts of 0-10 weight.

Daren

 

GUMP- What kind of oil pressure do you get with that?

 

No kidding. Why are you gonna do that? You must be wanting to rebuild your motor bad. For one that's way way thin and you only running 3.5 quarts?

I can say one thing....good luck and I hope your just real smart.

 

I am currently using 10W-40, I used to use 15W-50 in blower + N2O car. I realize it costs some hp, but I like the idea of protecting the bearing aginst the "shock" of the nitrous hit.

Rich Krause

 

This is a drag race only thing. It makes quite a big difference in ET.
I only run a factory pump and restrict all of the center drain backs in the lifter valley. As far as oil pressure goes, I really don't think that it is that important for the short period that I am at WOT. You would be really surprised at how good the bearings look when I tear the motors down at the end of the season.

Daren

 

Daren- I'm guessing you pull about 40 PSI off the line and close to zero through the traps in top gear?

I used to keep taking oil out of my motors at the track until I started to lose serious oil pressure at the top end. I wouldn't let it get to zero or anywhere near it, but back then I was not familiar with synthetic oils and their "magical" properties. I was just running parts store oil. It could get me a solid tenth, maybe a smidge more on a car only running 13s and shifting at 5500. On a faster, higher winding engine the benefits are probably magnified.

However, it should be noted that this is DRAGSTRIP ONLY kinda stuff. Driven on the street like this the motor would become a paperweight very quickly.