Engine oil recommendation for Turbocharged Airboat

[RDY4WAR]

You don't need a cooler. That's another benefit of using a boutique, top shelf tri-synthetic like those listed. They not only tolerate high heat but thrive in it. Where oils like T6 and other common API rated oils are pretty much done at 240-250°F, those oils listed will handle 280-300+°F without a problem. The HPL Bad Ass oil doesn't even see peak friction coefficient until 305°F, much less thermal breakdown. Hot oil is happy oil, especially with E85.

 

[mobilnissan1991]

Do you use the boat for work or personal use?

Nice setup, plenty of those running around here in South Louisiana.

 

[KeySmallBlock]

Do you use the boat for work or personal use?

Nice setup, plenty of those running around here in South Louisiana.

Just personal. I built the whole thing with a friend in our shops/garages. There's more water/swamp then there are woods around me so it makes more sense than a side by side or anything else.

 

[OCD-OCI]

Now this is a good topic for BITOG.

 

[KeySmallBlock]

I reached out to HPL. They are working up a few options. They believe their products will be fine for an extended OCI in my application and hold up exceptionally well.

I've never used that "top shelf" of an oil before.

I guess I may try it for a summer and see.

 

[AdmiralYoda]

I'm curious. Do the Gen-III/IV LS engines have a built in oil temp sensor? Considering that it probably isn't cheap to build a boat like this an oil sensor and dedicated temperature gauge seems like a good idea. I'd still consider adding an oil cooler because....why not?

I'm sure the turbo would be happy with cooler oil.

 

[RDY4WAR]

My take on heat is if the oil can't take the heat, use a better oil. A PAO/ester based synthetic is going to run cooler anyway just due to having a better friction coefficient (lower hydrodynamic friction = less heat generated) and a higher specific heat capacity (better heat absorption from surrounding metal), on top of having better oxidation resistance so it'll survive in higher temps for longer.

Like most all things in chemistry, heat drives additive reactivity. The hotter the oil, the better those additives are going to work and less fuel and water dilution you'll have in the oil. Like I say about my daughter when she wants habanero wings "If she can take the heat, let her eat."

 

[BrendanC]

I'm curious. Do the Gen-III/IV LS engines have a built in oil temp sensor? Considering that it probably isn't cheap to build a boat like this an oil sensor and dedicated temperature gauge seems like a good idea. I'd still consider adding an oil cooler because....why not?

I'm sure the turbo would be happy with cooler

no they don’t have built in oil temp sensors. The only vehicles that i know of that got temp sensors are ZO6/ZR1 Corvettes.

 

[oil pan 4]

Posting a potential unique situation, and looking for insight from the experts here. I've been researched and have a few ideas. I have built a forged bottom end, pretty aggressive cam/valve train LS (V8) with a turbo running on e85. It is making about 750-800 hp but I plan to turn it up to ~900 soon. This is on an airboat running in Florida so it never gets run below ~40°F but run consistently over 85-90F. It gets run for long amounts of time and we beat on them pretty hard. It sees boost constantly. I have been previously using Driven racing oils 10w40 but was looking for a more economical or potentially better oil to use. One other thing to add is the boat will sit for a few weeks at a time, so something with some corrosion protection would be nice.

I had two schools of thought. A cheaper oil but still quality that is easily available that I can change more frequent. Such as Penzoil Platinum Euro 5w40, or one of the other 5w40 that maybe meets the A40 spec. For a little more I can go with Amsoil Signature Max Duty 5w40 or their Premium Protection 10w40 (I already have a membership so it's ~$44ish a gallon). I need 8 quarts.

Or finally go all out with a top tier oil that is more expensive such as Redline, HPL, even stick with Driven it would just come at an extended oil change interval.

I am open to ideas and opinions I would like to keep 5w40 or 10w40.

Thank you all!

How hot does the oil get on those extended runs?
It sounds like the w part of the oil is just completely irrelevant for your application.
So you just don't even need to worry about a 5w or 10w oil.
At say 45f a 0w-40, 5w-40, 10w-40, 15w-40 and a straight 40 weight are all going to be nearly identical viscosity.

 

[oil pan 4]

I believe my bearing clearances are good for a 40wt oil, I would have to go back and find them. In my research the "more is better" isn't always the right approach. It's making plenty of oil pressure at the current weight. I guess I could try a 50wt. I just don't know if I really need it.
I don't believe the oil actually gets super hot. Cooling isn't a problem. There's an 82 inch prop that's pulling a tremendous amount of air over the radiator, engine (all aluminum), and oil sump. In fact the motor typically operates at or under about 190F. My Intake air temps are typically right around ambient as well under boost with the A2A intercooler getting that good airflow.

As requested here's a picture of the boat.

View attachment 265311

The only time bearing clearance becomes a problem is when you don't have enough oil pressure when hot at idle.

 

[RDY4WAR]

The only time bearing clearance becomes a problem is when you don't have enough oil pressure when hot at idle.

Bearing clearance dictates the viscosity (really the MOFT) needed to sustain full HD lubrication of said bearings.

.0016-.0021" = 20 grade
.0022-.0028" = 30 grade
.0029-.0034" = 40 grade
.0035-.0042" = 50 grade

If the viscosity is too high for the clearance, you get insufficient flow and increased hydrodynamic friction which increases bearing heat and thus bearing fatigue. If the viscosity is too low, you have insufficient oil film thickness to support the oil wedge, resulting in mixed and boundary lubrication regimes that damage the soft metals of the bearings. If there's insufficient pressure at hot idle or when revving, and there's no other problem like wrong pickup to pan clearance, stuck bypass, missing plug/restrictor, etc... then you need a higher volume pump, not a higher viscosity. Also, having 10 psi oil pressure at hot idle (in a healthy engine) is perfectly fine. You don't need 40 psi at idle like some people would lead to believe.

 

[burbguy82]

Economic and good......hard to do.

VR1 comes to mind first or Amsoil Premium 10w40 like others have said.

 

[97prizm]

Posting a potential unique situation, and looking for insight from the experts here. I've been researched and have a few ideas. I have built a forged bottom end, pretty aggressive cam/valve train LS (V8) with a turbo running on e85. It is making about 750-800 hp but I plan to turn it up to ~900 soon. This is on an airboat running in Florida so it never gets run below ~40°F but run consistently over 85-90F. It gets run for long amounts of time and we beat on them pretty hard. It sees boost constantly. I have been previously using Driven racing oils 10w40 but was looking for a more economical or potentially better oil to use. One other thing to add is the boat will sit for a few weeks at a time, so something with some corrosion protection would be nice.

I had two schools of thought. A cheaper oil but still quality that is easily available that I can change more frequent. Such as Penzoil Platinum Euro 5w40, or one of the other 5w40 that maybe meets the A40 spec. For a little more I can go with Amsoil Signature Max Duty 5w40 or their Premium Protection 10w40 (I already have a membership so it's ~$44ish a gallon). I need 8 quarts.

Or finally go all out with a top tier oil that is more expensive such as Redline, HPL, even stick with Driven it would just come at an extended oil change interval.

I am open to ideas and opinions I would like to keep 5w40 or 10w40.

Thank you all!

Mobil 1 5w-50 or Castrol 10w-60 used by a few BMW's. Or you Could send a note to hpl for a suggestion.

 

[KeySmallBlock]

I'm curious. Do the Gen-III/IV LS engines have a built in oil temp sensor? Considering that it probably isn't cheap to build a boat like this an oil sensor and dedicated temperature gauge seems like a good idea. I'd still consider adding an oil cooler because....why not?

I'm sure the turbo would be happy with cooler oil.

It's a water and oil cooled ball bearing turbo. I have some extra inputs on my terminator X I could temporarily add a temp sensor. I don't want to add the oil cooler if it's not necessary. It's just more complexity, more lines, opportunities for leaks, etc.

My take on heat is if the oil can't take the heat, use a better oil. A PAO/ester based synthetic is going to run cooler anyway just due to having a better friction coefficient (lower hydrodynamic friction = less heat generated) and a higher specific heat capacity (better heat absorption from surrounding metal), on top of having better oxidation resistance so it'll survive in higher temps for longer.

Like most all things in chemistry, heat drives additive reactivity. The hotter the oil, the better those additives are going to work and less fuel and water dilution you'll have in the oil. Like I say about my daughter when she wants habanero wings "If she can take the heat, let her eat"

This is interesting information. At what temperature is that type of oils "sweet spot"?

The only time bearing clearance becomes a problem is when you don't have enough oil pressure when hot at idle.

Hot idle is 30-35ish psi which is more than enough I believe.

Bearing clearance dictates the viscosity (really the MOFT) needed to sustain full HD lubrication of said bearings.

.0016-.0021" = 20 grade
.0022-.0028" = 30 grade
.0029-.0034" = 40 grade
.0035-.0042" = 50 grade

If the viscosity is too high for the clearance, you get insufficient flow and increased hydrodynamic friction which increases bearing heat and thus bearing fatigue. If the viscosity is too low, you have insufficient oil film thickness to support the oil wedge, resulting in mixed and boundary lubrication regimes that damage the soft metals of the bearings. If there's insufficient pressure at hot idle or when revving, and there's no other problem like wrong pickup to pan clearance, stuck bypass, missing plug/restrictor, etc... then you need a higher volume pump, not a higher viscosity. Also, having 10 psi oil pressure at hot idle (in a healthy engine) is perfectly fine. You don't need 40 psi at idle like some people would lead to believe.

This is my school of thought. More weight isn't always better and having the right oil pressure and viscosity throughout the rpm range is more critical.

Economic and good......hard to do.

VR1 comes to mind first or Amsoil Premium 10w40 like others have said.

So VR1 synthetic was something else I was looking at. I was going to mix their 10w30 and 20w50. With that I could almost change it monthly it's so cheap.

Mobile 1 5w-50 or Castrol 10w-60 used by a few BMW's. Or you Could send a note to hpl for a suggestion.

I am talking to HPL. I think I'm going to try one of their products for this summer coming up and see how it holds up if there's a good fit.

 

[burbguy82]

I am not sure that would be a great idea, if you do, i would strongly recommend an oil analysis. The chemistries might be very different between the grades.

One thing you have going for you is s the load on the engine. I would say being as all that is being moved is a fan, there is less load than lets say a truck towing a heavy trailer. Plus, you have a lot of cooling airflow to aid the oil's work.

 

[oil pan 4]

Then it comes down to operating temperature.
If it runs hotter than 230f then definitely use 40 weight. I would be surprised if it runs less than 220f on those extended power runs.

 

[KeySmallBlock]

I am not sure that would be a great idea, if you do, i would strongly recommend an oil analysis. The chemistries might be very different between the grades.

One thing you have going for you is s the load on the engine. I would say being as all that is being moved is a fan, there is less load than lets say a truck towing a heavy trailer. Plus, you have a lot of cooling airflow to aid the oil's work.

At this point it's Amsoil or HPL. I'm going to make the decision soon. I got a quote from HPL and it's honestly not as bad as I thought for what they claim it will do. There's only good thing about them on here too so I believe it will be backed up. I will say one thing their customer service is top notch. Makes me want to buy from them just to support the small business.

 

[burbguy82]

At this point it's Amsoil or HPL. I'm going to make the decision soon. I got a quote from HPL and it's honestly not as bad as I thought for what they claim it will do. There's only good thing about them on here too so I believe it will be backed up. I will say one thing their customer service is top notch. Makes me want to buy from them just to support the small business.

of course, one of the criteria you asked for was cheap....

Amsoil of HPL will undoubtedly serve perfectly.

Good luck

 

[RDY4WAR]

At this point it's Amsoil or HPL. I'm going to make the decision soon. I got a quote from HPL and it's honestly not as bad as I thought for what they claim it will do. There's only good thing about them on here too so I believe it will be backed up. I will say one thing their customer service is top notch. Makes me want to buy from them just to support the small business.

You won't get better customer service from any other oil company than HPL. They don't pump millions a year into advertising like other brands, allowing them to keep prices more reasonable. They make oils for Pro Mod, Top Alcohol, Pro Stock (and PSM), Monster trucks, Sprints, Late Models, race boats, and NASCAR. Their oils are bred from testing in all of these areas so there's a lot of R&D behind their formulas.