5W20 oil in winter?

[CandyCaneXj]

Anyone run 5w20? My 4.8 stroker has about 500 miles on it so time to change the oil again. I have been using comp cams 10w30 break in oil. Black K and N Filter, stock volume melling pump, and 180 degree thermostat. Engine runs completely smooth and basically no noise besides exhaust and fuel injectors. According to the factory 1994 sensor it has usually been around 60lbs cold and 30 warm. I assume it's somewhat accurate seeing how old engine was 55lbs cold and 20lbs warm using same sensor. Now with 30 degree mornings it's been around 65lbs cold and 35lbs after half an hour of driving. Somewhat dreading 0 degree weather. I'm definitly going to switch to 5w30 minimum but have been wondering if I should try 5w20 or perhaps 0w30? Also is there any negatives to using break in oil all the time? Not concerned about catalytic converter health.

[Russ Pottenger]

I wouldn't recommend the break in oil past 500 miles.

Lots of good oils out there, but I've been very happy with Comps 10w-30 synthetic blend. It's got the additive package that includes ZDDP, Molybdenum and detergents.

Don't worry about the catalytic converter warning.
Would only be an issue if you drove it 1,000,000 miles.

I sell it for $7.50 qt shipped, and $5.50 for the break in oil

[Cheromaniac]

I use 10W-40 semi-synthetic year round but where I live, the outside temp. varies from 70*F in the "winter" to 125*F in the summer. Cold start oil pressure is 60psi. Hot oil pressures are 25psi idle and 50psi on highway.
You could easily use 0W-30 in 30*F winters as that'll be thin enough to enable quick cold starts and thick enough to protect the engine when it's up to operating temp. You'll definitely need the ZDDP additive to protect the cam and lifters.