Another oil thread

[mcmmotorsports]

Ranger wrote:

[quote]I’m switching from Valvoline VR-1 to Brad Penn. It’s cheaper and has far better specs. I just got box of Brad Penn 15W40 and I’ll get a box of 20W50. Then I’ll do some testing and decide on a visc.

For the lazy…just use Mobil1 15W50. Not 15W50 “enhanced performance”, “enhanced mileage” or “enhanced breasts”, just 15W50. It’s not the cheapest and it’s not the best. But it is pretty cheap and pretty good.[/quote]

Isn’t taking oil advice from you like taking dieting advice from a fat chick?

I mean, how many engines have you exploaded?

[cwbaader]

I like to sample oil temp in the pan…a good indication of the temp of your bearings. CB

[Ranger]

turbo329is wrote:

Where is oil temp normally measured at? I always read that oil temp should be in the 200’s but my iS always shows the oil temp lower than coolant temp. While my cylinder head temp is 190 my oil temp is only 140. My brother has been the caretaker of my iS for the past few years and I’m not sure where he has all the sensors at.

There’s no perfect answer. Much of data collection isn’t so much absolutes but comparing against a baseline. No matter how you collect temp or pressure data, once you’ve been doing it a while you’ll be able to spot something out of the ordinary quickly. And this is true no matter if you are measuring temp before or after a cooler or radiator, or pressure in various places.

Oil pressure is tricky because it is so dependent on temp and oil choices. Consider…Thick oils show greater OP because they present more flow restriction. But thin oils exchange heat better so if you have an oil cooler they dump more heat and come back to the engine cooler. Since they come back cooler they come back thicker. So the lower visc oil could result in higher OP, if the OP is measured before the oil gets heated up again.

So it depends on oil choices and where you are measuring things. My point is that it’s hard to make absolute comparisons. My engine may run hotter or have higher OP then yours, but there could be a half dozen variables causing that, none of which are cause for concern. But if your hot OP drops 10psi over the course of a couple events and you’ve not changed anything, you know something is going on.

[Ranger]

mcmmotorsports wrote:

[quote]Ranger wrote:

[quote]I’m switching from Valvoline VR-1 to Brad Penn. It’s cheaper and has far better specs. I just got box of Brad Penn 15W40 and I’ll get a box of 20W50. Then I’ll do some testing and decide on a visc.

For the lazy…just use Mobil1 15W50. Not 15W50 “enhanced performance”, “enhanced mileage” or “enhanced breasts”, just 15W50. It’s not the cheapest and it’s not the best. But it is pretty cheap and pretty good.[/quote]

Isn’t taking oil advice from you like taking dieting advice from a fat chick?

I mean, how many engines have you exploaded? :P[/quote]

Mike, You don’t want me to build an engine for you. Heck, beyond something easy like swapping heads, I’m done with engine work. But there’s a lot of oil information out there if you’re willing to spend a couple months reading. My reading comprehension skills are at least average. From a 3rd party’s perspective it’s a lot more efficient to simply read the cliffnotes that some obsessed geek provides, then go read it all yourself and reach the same conclusions.

But if I go to the bother of trying to provide you with those cliffnotes, I’d encourage you to disagree with physics, chemistry and data, or keep a civil tongue.