Sanity check on oil for Supercharged C6 Corvette

[Nate_KY]

It's been a while since I went down this rabbit hole and unfortunately due to my home situation I just don't have a ton of hours to dedicate to research right now. I appreciate your grace in answering my question below. Just let me know if you need more information.

I recently installed a blower on my 2008 LS3 C6 which has about 55k miles on it. I'm running around 11 lbs of boost making 694 to the wheels. Running stock rings, pistons, rods, and crank. I drive it pretty hard most of the time. I never drive it below 45 degrees outside because of the tires. I put less than 5k miles a year on it, so oil change intervals are irrelevant to me. I've been running PUP 5w30 for years, but I want to make sure I'm protecting from engine wear as best I can. So, the big question now is (and I know it's a loaded question), do I stick with PUP or is there a better wear protection oil I need to consider based on the age, power, and OCI? How about weight?

Thanks all!

 

[JavierH19]

If it was mine I'd be using a euro 40 at minimum but if it's not gonna run in cold temps which I don't think Kentucky has even in cold snaps I'd rather use delvac extreme 15w-40. Don't think 15w-50 is necessary but that's something I'd use on the track but if it's street only delvac extreme 15w-40 is more than enough. Very stout additive pack with 1300 zinc and 1200 phos and higher hths than 0/5w-40's. PUP 5w-30 is ok but I still wouldn't use it.

I run 15w-40 in my 03 and 05 trucks and have been for a long time. They seem to love it. Dead silent valve train on both even after running for hours in the summer heat, with all 5/10w-30's I've tried they were definitely noisier at that high temp.

 

[Nate_KY]

That's diesel oil right?

 

[SR5]

I would run a 0W40 or 5W40 Euro A3/B4 oil like M1 0W40 FS or Castrol Edge 0W40 or Pennzoil Platinum Euro 5W40.

They are all Porsche A40 and MB 229.5 rated oils, which are very high quality standards.

They are thicker than standard ILSAC oils (more HTHS), with more zinc (about 1000 ppm) for wear protection. A good performance oil for the street.

 

[SR5]

That's diesel oil right?

Mixed fleet oil, suitable for both diesel and gas engines.

 

[Astro14]

An oil that meets MB 229.5 will meet every need of this engine with the blower.

Mobil 1 0W40 FS would be a great choice. Excellent HTHS. Cheap. Readily available.

 

[Patman]

PUP 5w30 is a great oil for a stock Corvette but with that kind of power you definitely need something more stout. At minimum you should be running an oil with an HTHS of 3.5, although I personally think closer to 4 would be ideal for that extra margin of safety when you are driving it hard with higher oil temperatures. What kind of oil temperatures do you typically see?

 

[userfriendly]

That's diesel oil right?

Yes. Delvac 1300 meets API CK4/SP, so it’s either a gasoline oil that meets Diesel specs or a Diesel oil that meets gasoline specs. Take your pick.
The Delvac Extreme may be viewed as over the top for your application with redundant zddp, tbn and dispersant package which could hurt performance.
Havoline 5w40, the API offering, not the Euro one is never mentioned on this site, but noack is 9.0, P 900 and Zn .105
M1 5w50 Supercar might be an option, it meets Dexos R. HTHS is probably around 4.5.

 

[BMWTurboDzl]

It's been a while since I went down this rabbit hole and unfortunately due to my home situation I just don't have a ton of hours to dedicate to research right now. I appreciate your grace in answering my question below. Just let me know if you need more information.

I recently installed a blower on my 2008 LS3 C6 which has about 55k miles on it. I'm running around 11 lbs of boost making 694 to the wheels. Running stock rings, pistons, rods, and crank. I drive it pretty hard most of the time. I never drive it below 45 degrees outside because of the tires. I put less than 5k miles a year on it, so oil change intervals are irrelevant to me. I've been running PUP 5w30 for years, but I want to make sure I'm protecting from engine wear as best I can. So, the big question now is (and I know it's a loaded question), do I stick with PUP or is there a better wear protection oil I need to consider based on the age, power, and OCI? How about weight?

Thanks all!

694 HP at the wheels? So that's around 750hp at the crank? Wow!

On a highly modified engine with stock internals my first thought goes out to Redline High Performance 0w40 with a HTHS of 4.1 cP.

 

[Nate_KY]

PUP 5w30 is a great oil for a stock Corvette but with that kind of power you definitely need something more stout. At minimum you should be running an oil with an HTHS of 3.5, although I personally think closer to 4 would be ideal for that extra margin of safety when you are driving it hard with higher oil temperatures. What kind of oil temperatures do you typically see?

Thanks for the detailed input. As for temps, that's a great question. I'll be out and about today so I'll take a look.

 

[JavierH19]

I agree with the others basically anything that has at least 3.5 Hths will do but anything beyond 4.5 of 15w-50 is unnecessary. Standard 5w-30 is around 2.9-3.1 which is a bit low for a high power engine but not terrible but not something I'd use. Almost all euro 30's are 3.5-3.6. Euro 40's are can range from 3.5-3.7 for off the shelf options while boutique euro 40 oils can do almost 4.2. I've never seen a 15w-40 be below 4.0 but most are 4.1-4.2 and boutiques can do around 4.5.

 

[Nate_KY]

694 HP at the wheels? So that's around 750hp at the crank? Wow!

On a highly modified engine with stock internals my first thought goes out to Redline High Performance 0w40 with a HTHS of 4.1 cP.

Yeah, she's making some pretty good power so far. I've seen drivetrain loss for manual in the neighborhood of 15-18%, so probably closer to 780-800 crank. But, when you're up in that range, you're splitting hairs LOL.

 

[wpod]

How long can you hold WOT ? A guy in the housing tract has a Hellcat Challenger and I hove gone for rides and it doesn't take long to run out of road.

 

[edyvw]

An oil that meets MB 229.5 will meet every need of this engine with the blower.

Mobil 1 0W40 FS would be a great choice. Excellent HTHS. Cheap. Readily available.

^THIS!!!

 

[PoorMans180SX]

Lol @ using Mercedes certs for loosey goosey LS engine oil recommendations. Why would you run 0w40 when thicker is just cheap insurance? I’m sure he’s not concerned about mileage. Chevrolet recommends 50 weight for the track, and this level of power certainly warrants it on the wet noodle aluminum LS block.
5w50 Mobil 1 racing or some other brand of 5w50/10w50/15w50, I’m partial to HPL personally.

 

[Nate_KY]

How long can you hold WOT ? A guy in the housing tract has a Hellcat Challenger and I hove gone for rides and it doesn't take long to run out of road.

Depends on location and time of day, but either way, it doesn't take long to get to triple digits.

 

[JavierH19]

Lol @ using Mercedes certs for loosey goosey LS engine oil recommendations. Why would you run 0w40 when thicker is just cheap insurance? I’m sure he’s not concerned about mileage. Chevrolet recommends 50 weight for the track, and this level of power certainly warrants it on the wet noodle aluminum LS block.
5w50 Mobil 1 racing or some other brand of 5w50/10w50/15w50, I’m partial to HPL personally.

Yes that's true the bearings are all wide open and make a rod knock sound after the first few seconds after an oil change until pressure builds and the cam cap bolts are are all loose and the heads aren't even tightened down with bolts missing on some of the head studs from the factory. The crank and cam clearances and tolerance variance is definitely not very close or sometimes identical to all other modern performance engines from germany... 5w-50 shears down to a 40 in no time. fords 5w-50 shears to a 30 which is worse.

 

[userfriendly]

I wonder what the shear stability is with M1 Dexos R 5w50?
Maybe for fun I’ll run it for 10,000 miles in a LML Duramax and find out.

 

[Patman]

Yes that's true the bearings are all wide open and make a rod knock sound after the first few seconds after an oil change until pressure builds and the cam cap bolts are are all loose and the heads aren't even tightened down with bolts missing on some of the head studs from the factory. The crank and cam clearances and tolerance variance is definitely not very close or sometimes identical to all other modern performance engines from germany... 5w-50 shears down to a 40 in no time. fords 5w-50 shears to a 30 which is worse.

It’s this very reason why I never recommend 5w50 to anyone. You are better off with a 5w40 that will hold it’s viscosity a lot longer and will quite possibly be thicker than the 5w50 will be after a few thousand miles.

 

[PoorMans180SX]

Do Germain engines routinely walk the main caps and spin main bearings at 600wtq like an LS? Didn’t think so. The aluminum LS block is not that strong, and not that stiff.

If you want to buy trash 5w50, sure, or just run 15w50 or 20w50 since you apparently can’t find 5w50 with stable polymers (hint, it’s HPL).