engifineer

They were pretty tough. I was broke and drove a 75 Chevy with a 350 that had a rod knock for months until I had enough to rebuild it. Wore over a 1/8" groove in the crank before I did. Scared the hell out of anyone near it when I started it because it would hammer so loud! Never came apart lol. Replaced the crank, that rod, cleaned it up and put it back together and ran like a champ until someone stole it and took it out by the river and did donuts at WOT until they blew up the motor

But, be careful about running higher weight oil in this car. With the way it is designed to run and be driven, I would prefer putting in more oil than running a higher weight and possibly sacrificing oiling performance.

s2000Junky

10/40 works fine/safe in this engine and would be as high a viscosity as I would go.

I would still consider replacing the valve seals just because it may solve some of the oil consumption and can be done for around $400- $600 tops. So you have to decide if its worth that money to find out or keep running it as is.

Chuck S

Engine lubrication depends on oil flow, not oil sitting on the surfaces. Oil that's too thick will not flow to spec. 10W-30 and 5W-40 grades are the specified oils for this car. The upper number is what we're concerned about here. I'd also not go thicker than 40 grade. The lower number helps on startup.

Had an engine oil analysis? This will show what, if anything, is wearing abnormally. Visit Blackstone Labs and request their free oil bottle. I think the actual analysis is under $30 and they have a nice database on S2000 engines.

-- Chuck

Live Fast

Yes, just as Chuck says the "Cold weather" weight for the oil is probably the one to use to see if consumption gets better. From standard 10W30 the 5W-40 oil will be less thick on start ups. You should never increase this number unless the engine builder/OEM specify a track oil weight which usually they don't recommend on the street. The 5W-40 will just be slightly thicker when at operating temperature.

If you want to try Amsoil it seems to have the best sheer strength and resistance to burning off, I forget the scientific term for it.

Performing a valve adjustment then leakdown testing the engine will show where your issue lies. If you have above 15% leak down in one cylinder through the crankcase it's most likely the rings or the cylinder liner

With some LS style engines we have played with we also had luck using a small amount of Marvel Mystery oil squirted ontop of the piston and turning the engine over a few times before sitting for a day and starting. It will smoke for a bit but the day after when cold we noticed less leakdown and a bump in compression. It might help or not.

We didn't perform hot tests since it's a PITA on LSx engines

windhund116

I'm not sure I'd use Amsoil ($$$) in a car burning a lot of oil.

Remember, my story is based on 60 year old cast iron US V8 technology. Just an anecdotal tale. For his AP1 S200, I'd prolly go to 10W-40. And really check the dipstick.

rakkzi

I was considering it! A friend told me about when they did it and I was curious about it. I think they even used the same place (blackstone labs)

I'm planning to boost it down the line and I want to make sure that the internals are in good shape before I do.

Yeah, in hindsight I probably wouldn't either. I wanted to see if the "good stuff" would make a difference to the consumption as compared to the stuff you can get at walmart.

engifineer

I am not all that convinced Amsoil is that much more "good stuff" than many other oils in practical application. Their sales folks are like snake oil salesman and have come up with some great lines of shit. I have known a couple of them lol. I have used it in the past, but honestly do not think it is worth spending the extra money. There is a LOT of hype in the oil industry! They can point to numbers that seem better, but is it really going to show up in any sort of actual results in the use case it is intended for? I mean, we see this all the time in engineering and product development. "Over-engineered" many times mean no usable benefit other than on paper and more cost to the end user. If it meets the requirements of its intended use, it many times means nothing at all for it to "exceed" those requirements if you know what I mean. In some instances this is not the case, but in many it is.

jyeung528

i agree. it's the wonders of marketing.

if i'm not mistaken, they obtain their base oil probably from Exxon-Mobil, and their additive package comes from a popular additive company as well. their expertise is in marketing.

windhund116

Yes the hard, cold fact is there are very few companies refining or synthesizing the base products. Additives is where the market varies.