yep. this is sad. so sad.

 

Royal Purple 5W30, I swear it's given my SS more HP.

 

German castrol 0w-30 here year round

 

I would not use anything thicker than 10W-30. 10-40, 15-40, 20-50 straight 30w are all too thick. 90% of harmful engine wear comes on start up. Thinner oils lubricate better at startup. Thicker oil gives higher oil pressure but less flow.

I recommend 5W-30 year round. If its an extremely hot climate then use 10W-30.

 

mabe people should read this

http://www.synthetic-oil-tech.com/d....weight_oil.htm

 

what do you guys think of amsoil 10w-40? would you guys really believe the 25,000 mile change or no? and what kind of filter would be best for it?
thanks

 

I use amsoil 0-30. I change it once a year in my Z (only driven 1k miles or so a year), and in my beater (15k miles a year), and twice a year in my tahoe (every 10k or so). Its supposed to be good to 25k miles, or 1 year. I dont drive one car that much. You are supposed to change the oil filter every 12k if you go that long though. Oil is cheap, even amsoil, when compared to building an engine. I just change mine enough that I know I wont have a problem.

 

do you think 0-30 is good for warm-hot weather? and what brand oil filter would you use to 10k miles? mobil? bosch?

 

So I'm guessing that the 5w-30 is fine for my car and weather conditions? The weather is weird here compared to the rest of the country. Only in NE Ohio can you run the heater and air conditioner on the same day.

 

And you would know more than those of us who actually have looked at used oil analysis reports and such right?

PLEASE everyone look at that link I posted, most of you will find out just how WRONG you are in that you thought you knew about oil. If you search in the UOA section for "LT1" you can find out exactly what wildly popular oil for this motor performs poorly is the most commonly used weight and can find out what actually does work well. Talking real measured data in personal vehicles, not some ball bearing marketting gimmick or "used such and such forever" crap.
Think of it as dyno charts and timeslips for oil, those are all that matter in proving a performance mods worth right.

 

The amsoil 0-30 is actually closer to 40w than 30 from what Ive heard. It gets a little thicker as it gets old. Mobil 1 on the otherhand starts out thin, and ends up closer to a 20W. At least thats what Ive read from threads here where people have done the analysis.

I use either amsoil, or ac delco filters usually. Just amsoil filters for the Z though.

 

If your going to run mobil one, run a 40 weight. They show the best wear results on a LT1. Ideally though, is the German Castrol Syntec

 

Would I still run a 40 weight on castrol as well?

 

No. Running too high a viscosity gains you little in oil film performance but has a pretty negative impact on fuel economy.

If you have good warm oil pressure, you'll be fine with 5W-30....

 

I run the thinnest oil I can that still gives decent oil pressure... less to turn the pump/more horsepower!!

Who the hell needs 40 psi at idle lol... as long as I have 10-20 psi, I don't worry about it.

I purposely built my motor loose so that I wouldn't have high oil pressure. Oils better at start-up, too.