Oil for Cammed LS?

Messages
5
Location
SF Bay Area
Hey guys, long time lurker here just looking to see what you guys think about the oil type that was recommended to me for my mild LS2 build. Let me give you the rundown on the engine and how it's used:

-2007 Corvette w/LS2, MZ6 manual trans, about 55k miles. Doesn't burn a drop of oil.
-Cam Motion cam with 227/235 duration, ~.615/.615 lift, 113+2 advance. Lot's of lope with around 8.5* of valve overlap.
-Johnson 2110 drop in lifters
-Melling high pressure oil pump (10295 iirc). Cold oil pressure = ~45lbs, operating temp ~34lbs
-C5R timing chain + damper setup
-Upgraded pushrods (can't remember length, brand)
-Trunion bearing upgrade for the rockers
-BTR double valve springs w/titanium retainers
-1 7/8 American Racing Headers to full 2 1/2 X-Pipe, catback
-Stock intake, stock 243 heads, stock bottom end
-Custom tune
-Located in the SF Bay Area (for general weather and altitude questions)

The car is usually used as a weekend car but lately I've been using it for the daily commute. I originally built the engine to be a mean street / backroads car that would eventually be an amateur road race setup with an emphasis on reliability as I do romp on it pretty good every few times I take it out but I wasn't willing to sacrifice reliability for power. As per my tuner I'm running Redline 10w40 and change the oil every 2500 miles (as per his recommendation) but can't help thinking that it's a bit thick of an oil for an LS engine? On startup I do have a split second of a clacking sound, it sounds almost like slack in the valvetrain that's being taken up when the lifters are filled with oil, however my tuner said he set the preload of the lifters on the looser side so they don't pump up at high rpm. Regardless, this is a daily street driven car that I use to take long road trips with the occasional freeway or backroads race. Considering that 5w30 Mobil 1 is the factory fill, would I be better off with a slightly thinner Redline 5w40 (vs. the 10w40 I'm using now), or perhaps something else entirely?

TIA for your answers.
 
Last edited:
Messages
4,632
Location
Decatur AL USA
Hey guys, long time lurker here just looking to see what you guys think about the oil type that was recommended to me for my mild LS2 build. Let me give you the rundown on the engine and how it's used:

-2007 Corvette w/LS2, MZ6 manual trans, about 55k miles. Doesn't burn a drop of oil.
-Cam Motion cam with 227/235 duration, ~.615/.615 lift, 113+2 advance. Lot's of lope with around 8.5* of valve overlap.
-Johnson 2110 drop in lifters
-Melling high pressure oil pump (10295 iirc). Cold oil pressure = ~45lbs, operating temp ~34lbs
-C5R timing chain + damper setup
-Upgraded pushrods (can't remember length, brand)
-Trunion bearing upgrade for the rockers
-BTR double valve springs w/titanium retainers
-1 7/8 American Racing Headers to full 2 1/2 X-Pipe, catback
-Stock intake, stock 243 heads, stock bottom end
-Custom tune
-Located in the SF Bay Area (for general weather and altitude questions)

The car is usually used as a weekend car but lately I've been using it for the daily commute. I originally built the engine to be a mean street / backroads car that would eventually be an amateur road race setup with an emphasis on reliability as I do romp on it pretty good every few times I take it out but I wasn't willing to sacrifice reliability for power. As per my tuner I'm running Redline 10w40 and change the oil every 2500 miles (as per his recommendation) but can't help thinking that it's a bit thick of an oil for an LS engine? On startup I do have a split second of a clacking sound, it sounds almost like slack in the valvetrain that's being taken up when the lifters are filled with oil, however my tuner said he set the preload of the lifters on the looser side so they don't pump up at high rpm. Regardless, this is a daily street driven car that I use to take long road trips with the occasional freeway or backroads race. Considering that 5w30 Mobil 1 is the factory fill, would I be better off with a slightly thinner Redline 5w40 (vs. the 10w40 I'm using now), or perhaps something else entirely?

TIA for your answers.

Based on HTHS Redlines are really more like 50 grades. M1 15W-50 or a RL 40 Grade are good track oils for 250F+ Sump Temps. You still have a roller cam. You don't need an especially high amount of ZDDP or HTHS in that application for street oil temps. Something along the lines of M1 5W-30 ESP or M1 ESP 0W-40 would be fine. Something between 3.5 - 4.0 HTHS and that plays nice with your emissions equipment (assuming you still have cats in Cali). If you want to stick to RL try one of their 5W-30 but I don't really see it as ideal for that application. Their street oils would work but in that case I would just buy it in the Kendall GT-1 Bottle and save the RL Tax.
 

J-Mama

Thread starter
Messages
5
Location
SF Bay Area
Why would the 10W-40 be too thick?

I've loosely read that LS' are especially picky with oil weight in regards to how quickly they can get the oil through the system on startup and how the valvetrain sounds at idle, and I'm still running the stock bottom end bearings (OEM clearances). What I've read warns not to go too thick on the oil with these engines as it could cause issues.
 

OVERKILL

$100 Site Donor 2021
Messages
46,022
Location
Ontario, Canada
With a stock bottom end and heads, you'd probably be just fine on the factory spec oil, it's not like you've put on a turbo or supercharger either. GM ran M1 0w-40 in the Race Program Corvettes, and may still, unless they've switched to the ESP 0w-40 now. You'd likely be perfectly safe running that.
 

Strokenmerc

Site Donor 2021
Messages
196
Location
Va
What filter are you running? Could be the ADBV in the filter but to answer your question I would be perfectly fine with M1 0w40 or M1EP 10w30.
 
Messages
10,693
Location
Jupiter, Florida
Since it's not still a stock engine, you can throw the factory oil spec out the window. I would use what the tuner recommended.


I'm going to say the same. My reasoning is as follows. We don't know what your operational oil temperature is, when operated "hard". Oil viscosity is only marginally different once operational temperature is reached between small differences in choices 10W-40 vs 4W-40. However, when oil temperatures reach operational extremes, oils with higher HTHS will provide protection when thinner choices will not.

Also oils with a lower viscosity spread sometimes have fewer viscosity index improvers, leading to less shear over time. Among quality oils, a 5W-50 will likely shear faster than a 20W-50.

LS engines operating at the local road race track here in hot-n-humid S. FL (PBIR) have a tendency to reach some pretty righteous numbers. I've seen 300 degree oil temps in street driven race cars. These guys properly choose a 50 viscosity synthetic. Often M1, 15W-50.

Serious teams often use a much thinner oil, but they have excellent oil temperature management systems, and almost always use a dry sump system. These guys can use a 5W-20 and maintain a 200-210 degree oil temp!


Conclusion; your engine builder probably chose that oil either through successful experience (I know this works because it works) or through knowing your setup and it's viscosity needs (I know you don't have active oil temperature management and the engine oil temp is likely to climb under harsh conditions)
 
Last edited:

J-Mama

Thread starter
Messages
5
Location
SF Bay Area
I'm going to say the same. My reasoning is as follows. We don't know what your operational oil temperature is, when operated "hard". Oil viscosity is only marginally different once operational temperature is reached between small differences in choices 10W-40 vs 4W-40. However, when oil temperatures reach operational extremes, oils with higher HTHS will provide protection when thinner choices will not.

Also oils with a lower viscosity spread sometimes have fewer viscosity index improvers, leading to less shear over time. Among quality oils, a 5W-50 will likely shear faster than a 20W-50.

LS engines operating at the local road race track here in hot-n-humid S. FL (PBIR) have a tendency to reach some pretty righteous numbers. I've seen 300 degree oil temps in street driven race cars. These guys properly choose a 50 viscosity synthetic. Often M1, 15W-50.

Serious teams often use a much thinner oil, but they have excellent oil temperature management systems, and almost always use a dry sump system. These guys can use a 5W-20 and maintain a 200-210 degree oil temp!


Conclusion; your engine builder probably chose that oil either through successful experience (I know this works because it works) or through knowing your setup and it's viscosity needs (I know you don't have active oil temperature management and the engine oil temp is likely to climb under harsh conditions)

This is the information I was looking for, if I'm understanding this correctly it seems that there is a marginal difference in viscosities at operating temps but the 10w40 has higher shear rating and temperature stability, so this would be a good choice for a hard run engine. The highest I've gotten my oil temps are ~240deg. when driving hard and about 220deg. sitting in traffic on a hot day so not too bad (I asked him for a more conservative tune that's able to be driven in all conditions). The only oil temp management I have at the moment is the stock Z51 engine oil cooler which I've found works adequately for romping around and a bit of backroads racing.
 
Messages
10,693
Location
Jupiter, Florida
I would not speak in absolutes when comparing oils of similar 100c ratings. But it 'seems' true that a modern 0W-40 will shear faster than a robust 10W-40 such as Redine or Amsoil. It's also likely that the HTHS (viscosity at 150c) is higher in the 10W-40. People make the assumption that the 40 rating gives equivalent performance. That's often just not so and I've seen 5W-30 oils outperform 0W-40 oils in high shear motorcycle use.

As for such frequent oil changes, I'd say 5000 miles is generally fine. Perform a few UOA tests and find out.
 
Messages
17,231
Location
Upper Midwest
I've loosely read that LS' are especially picky with oil weight in regards to how quickly they can get the oil through the system on startup and how the valvetrain sounds at idle, and I'm still running the stock bottom end bearings (OEM clearances). What I've read warns not to go too thick on the oil with these engines as it could cause issues.
No. As long as the winter rating isn't completely inappropriate for the starting conditions the oil will "get through the system" the same.
 

J-Mama

Thread starter
Messages
5
Location
SF Bay Area
I would not speak in absolutes when comparing oils of similar 100c ratings. But it 'seems' true that a modern 0W-40 will shear faster than a robust 10W-40 such as Redine or Amsoil. It's also likely that the HTHS (viscosity at 150c) is higher in the 10W-40. People make the assumption that the 40 rating gives equivalent performance. That's often just not so and I've seen 5W-30 oils outperform 0W-40 oils in high shear motorcycle use.

As for such frequent oil changes, I'd say 5000 miles is generally fine. Perform a few UOA tests and find out.

I recently ordered an oil test kit from Blackstone to see exactly where I'm at, still waiting on it in the mail. I was told to change the oil that often purely because of gas dilution of the oil due to high exhaust reversion from valve overlap. Is this something to be concerned about?
 
Messages
108
Location
NY
For reference I have a 2002 z06 with a larger cam, PP heads and plan on running PP Euro L 5w30. Ran any old 5w30 previously and UOA came back good. When I had the blower then the 5w30 got its ass kicked but that’s another story. Plus the PP Euro L is basically a 40 weight. My STI which is known to put up a fight against oils loves it.
 
Messages
17,231
Location
Upper Midwest
I recently ordered an oil test kit from Blackstone to see exactly where I'm at, still waiting on it in the mail. I was told to change the oil that often purely because of gas dilution of the oil due to high exhaust reversion from valve overlap. Is this something to be concerned about?
Considering that Blackstone is apparently incapable of distinguishing between mechanical shear and fuel dilution, even if they show a viscosity deviation you won't know what caused it.
 
Messages
16,006
Location
N.H, U.S.A.
Hey guys, long time lurker here just looking to see what you guys think about the oil type that was recommended to me for my mild LS2 build. Let me give you the rundown on the engine and how it's used:

-2007 Corvette w/LS2, MZ6 manual trans, about 55k miles. Doesn't burn a drop of oil.
-Cam Motion cam with 227/235 duration, ~.615/.615 lift, 113+2 advance. Lot's of lope with around 8.5* of valve overlap.
-Johnson 2110 drop in lifters
-Melling high pressure oil pump (10295 iirc). Cold oil pressure = ~45lbs, operating temp ~34lbs
....
...
The car is usually used as a weekend car but lately I've been using it for the daily commute. I originally built the engine to be a mean street / backroads car that would eventually be an amateur road race setup with an emphasis on reliability as I do romp on it pretty good every few times I take it out but I wasn't willing to sacrifice reliability for power. As per my tuner I'm running Redline 10w40 and change the oil every 2500 miles (as per his recommendation) but can't help thinking that it's a bit thick of an oil for an LS engine? On startup I do have a split second of a clacking sound, it sounds almost like slack in the valvetrain that's being taken up when the lifters are filled with oil, however my tuner said he set the preload of the lifters on the looser side so they don't pump up at high rpm. Regardless, this is a daily street driven car that I use to take long road trips with the occasional freeway or backroads race. Considering that 5w30 Mobil 1 is the factory fill, would I be better off with a slightly thinner Redline 5w40 (vs. the 10w40 I'm using now), or perhaps something else entirely?


Here is what GM performance recommend on their Hi-Po Crate LS376 / 525 horsepower crate engine:
__________________
Camshaft LS376/525:............................... Hydraulic roller tappet Lift:............................................................ 525” intake, .525” exhaust Duration: ................................................... 226° intake, 236° exhaust @.050” tappet lift Centerline: ................................................ 110° LSA Rocker Arm Ratio: .................................... 1 .7:1 Oil Capacity: ............................................. 5.5-quart (with filter) Oil Pressure (Minimum, with hot oil):........ 6 psig @ 1000 RPM .................................................................. 18 psig @ 2000 RPM .................................................................. 24 psig @ 4000 RPM Recommended Oil:................................... DEXOS1 Oil Filter: ...................................................AC Delco part # PF48 Fuel:..........................................................Premium unleaded-92 (R+M/2) Maximum Engine Speed: ......................... 6600 RPM Spark Plugs: ............................................. GM 12609877 ..................................................................AC Delco # 41-985 Spark Plug Gap: ...................................... 040” Firing Order: ............................................. 1-8-7-2-6-5-4-3 Information may vary with application. All specifications listed are based on the latest production information available at the time of printing.
TIA for your answers.


________________

I have a fair amount of Gen I SBC build experience ( along with other marques ). Most of this is experience transferable to all engines, though some have their quirks.

1) Your "tuners" cam choice has too much lift for daily street driving, IMO. Plus a 0.600"+ cam should use solid tappets.
2) This build does not warrant a hi volume oil pump. That is lost HP.
3) The builder (tuner?) likely set the tappet pre-load at 1/4 turn or less. You will get some racket on warm-up.

My rec would be to go to a REDLINE 30 grade or Mobil racing. Yo can always call REDLINE and chat.

Enjoy the car! - Ken

p.s: GM performance specs a "synthetic" 5W30 oil on their warrantied monster crate Gen VI big blocks.
 
Messages
108
Location
NY
Here is what GM performance recommend on their Hi-Po Crate LS376 / 525 horsepower crate engine:
__________________
Camshaft LS376/525:............................... Hydraulic roller tappet Lift:............................................................ 525” intake, .525” exhaust Duration: ................................................... 226° intake, 236° exhaust @.050” tappet lift Centerline: ................................................ 110° LSA Rocker Arm Ratio: .................................... 1 .7:1 Oil Capacity: ............................................. 5.5-quart (with filter) Oil Pressure (Minimum, with hot oil):........ 6 psig @ 1000 RPM .................................................................. 18 psig @ 2000 RPM .................................................................. 24 psig @ 4000 RPM Recommended Oil:................................... DEXOS1 Oil Filter: ...................................................AC Delco part # PF48 Fuel:..........................................................Premium unleaded-92 (R+M/2) Maximum Engine Speed: ......................... 6600 RPM Spark Plugs: ............................................. GM 12609877 ..................................................................AC Delco # 41-985 Spark Plug Gap: ...................................... 040” Firing Order: ............................................. 1-8-7-2-6-5-4-3 Information may vary with application. All specifications listed are based on the latest production information available at the time of printing.
TIA for your answers.


________________

I have a fair amount of Gen I SBC build experience ( along with other marques ). Most of this is experience transferable to all engines, though some have their quirks.

1) Your "tuners" cam choice has too much lift for daily street driving, IMO. Plus a 0.600"+ cam should use solid tappets.
2) This build does not warrant a hi volume oil pump. That is lost HP.
3) The builder (tuner?) likely set the tappet pre-load at 1/4 turn or less. You will get some racket on warm-up.

My rec would be to go to a REDLINE 30 grade or Mobil racing. Yo can always call REDLINE and chat.

Enjoy the car! - Ken

p.s: GM performance specs a "synthetic" 5W30 oil on their warrantied monster crate Gen VI big blocks.

The LS376 is not a big block.

.600 to .650 lift for a DD is going to be fine with a proper setup.

Anyone who doesn’t measure pushrod length properly and just does 1/4 turn deserves noise.

Hydraulic lifters are not even close to being needed to switch out for solid lifters at that lift. OP even has upgraded lifters so it won’t even sweat.
 
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