Blast From The Past

Here's something that's not been on the market since my Comet was still fairly new...

Barely sloshes at room temp, must be straight 50W or so, can has no weight grade...

 

why would you think "racing motor oil" would be that heavy?

 

Cuz back in the day I can't remember any Racing oil that wasn't 40W, even 60W was avail...

 

When I first started in stock car racing, 50W racing oil was the standard but no so much these days

 

Machining procedures and materials are soooo much better now, bearing clearances can be safely reduced to where 5w oil will work just fine...

 

has come a long way...

XPR 0W-5
is our lowest viscosity engine oil designed for the most competitive classes such as Pro Stock, Pro Stock Bike, Comp Eliminator and NASCAR Cup (qualifying). The ultra-low viscosity provides the most horsepower possible by keeping parasitic losses to an absolute minimum while providing unparalleled protection.

 

You don't want to use that 0W-5 in anything but a race engine and then as noted for NASCAR, just for qualifying... For ¼ mile runs, oil temp is still low enough that 5W oil is thicker than a hot 30 or 40W..

A few years back Stewart-Haas(I believe) tried similar for their race oil, yep engines blew up approx 2/3 through...

 

The Stewart-Haas racing team now runs 20 quarts of Mobil 1 synthetic oil in their engines though I don't know what weight.

 

Came across a recent ad for Amsoil "Racing oil". It was 100% synthetic 5W20.

MD

 

Here is the Amsoil ad.



MD

 

Kewl I'll be checking HTST, cSt, NOACK etc... My bet it's a "heavy" 20W meaning at 100C* it's all but in 30W range... Funny thing about oil is there are cuts off for each grade, 20w ends at 9.2 cSt, 30w begins at 9.3, per SAE grades there is no in-between, it's one or other...

I've thought of running 5W-20 in my T-Bird along with a 160* T-stat, to keep oil temps down... But besides being a weekend racer it's a year rounder so has to provide heat in winter and cool in summer...

 

To confuse the issue Amsoil still makes a high viscosity racing oil all the way to 60 weight. Different "stokes" for different folks!

MD

 

Nitro cars run 50 or 60 weight oil, helps with the fuel dilution. Ever seen what comes out of the pan on a fueler after one run? Looks like a mix baby diarrhea and good old 3M "monkey snot" yellow adhesive...

 

Ughhh, so much for finishing breakfast... Kiddin'

In a low RPM/High Hp condition(comparatively speaking) the thick oils reduce bearing stress... At full throttle off the line, nitro engines are turning what? 2500 RPM? And making 3000+ HP? There's so much torque that with thin oils bearing is slammed into crank... No doubt also happens with the 60W generally used but at least to a lesser degree...

 

I remember the Castrol 20-50 Racing oil in the '70's.