New Engine. Need help deciding on an oil

[BrocLuno]

Originally Posted By: ARCOgraphite
flow is not the main concern here - its maintaining journal float under big loads. That take some viscosity.


+1 That's why you do what the builder says. We don't know what the bearing clearances are... We can assume 0.002"... But they could be 0.0035" and then we'd be asking for 20W-50 too. We also don't know the piston to wall numbers, so do what the builder says ...

 

[KL31]

Well the first number in the oil can never be low enough so why not a 10w50 instead? That way you get better cold start flow but still maintain that required 50 grade.

 

[Merkava_4]

How's that 20W-50 gonna jive with multi-cylinder displacement and variable cam timing ?

 

[FCD]

I would suggest Mobil 1 15W-50 or Redline 0W40

 

[ATex7239]

I'm going to just echo what most are saying here; don't see area a good reason to use 50, 40 seems more appropriate.

But, I'm not the engine builder. Maybe he has some info I'm missing.

 

[Kuato]

Originally Posted By: Mccull
They weren't specific. Just said Joe Gibbs break in oil. I'm not going to ask because it allows me a bit of freedom that they weren't specific.


Apparently Joe Gibbs break in oil comes in 15w50, 10w40 and 5w30. Taking both of your builder's suggestions into account, I'd use the 15w50 for break in. If the builder doesn't have an "after break in" suggestion, well, there's some good 5w50 synthetics out there, and as mentioned 5w40 Rotella T6 would probably be a good fit.

 

[Mccull]

No VVT and DOD on this engine anymore. It all has been deleted. I am not sure on the clearances either. When I voiced my concern about the 20w50 is when they said use Joe Gibbs so it seems they are ok with Mr using a lower viscosity. The 20w50 recommendation came from a general break in procedure they gave me. The break in procedure states, "20w50 is best for high hp big cam motors." It doesn't give the reasoning as being larger clearances. I wouldn't qualify my engine as "high hp big cam."

So based off that and your guys opinions it seems I would be ok with somewhere in the middle of what Joe gibbs offers and use their 10w40?

 

[Kuato]

Originally Posted By: Mccull
No VVT and DOD on this engine anymore. It all has been deleted. I am not sure on the clearances either. When I voiced my concern about the 20w50 is when they said use Joe Gibbs so it seems they are ok with Mr using a lower viscosity. The 20w50 recommendation came from a general break in procedure they gave me. The break in procedure states, "20w50 is best for high hp big cam motors." It doesn't give the reasoning as being larger clearances. I wouldn't qualify my engine as "high hp big cam."

So based off that and your guys opinions it seems I would be ok with somewhere in the middle of what Joe gibbs offers and use their 10w40?


Ah, so the recommendation is not specific for your engine; plus you said above that the lower end is stock so your suggestion of 10w40 for break in sounds reasonable. THEN switch to T6 at 5000 miles and drive on...

 

[Mccull]

Originally Posted By: Kuato
Originally Posted By: Mccull
No VVT and DOD on this engine anymore. It all has been deleted. I am not sure on the clearances either. When I voiced my concern about the 20w50 is when they said use Joe Gibbs so it seems they are ok with Mr using a lower viscosity. The 20w50 recommendation came from a general break in procedure they gave me. The break in procedure states, "20w50 is best for high hp big cam motors." It doesn't give the reasoning as being larger clearances. I wouldn't qualify my engine as "high hp big cam."

So based off that and your guys opinions it seems I would be ok with somewhere in the middle of what Joe gibbs offers and use their 10w40?


Ah, so the recommendation is not specific for your engine; plus you said above that the lower end is stock so your suggestion of 10w40 for break in sounds reasonable. THEN switch to T6 at 5000 miles and drive on...


T6?

 

[vronline]

Rotella T6 5W-40

 

[ammolab]

VR-1 comes in 10W-30 also. I mix this with the 20W-50 for my bike to make a great "sort of 15W-40".

 

[cronk]

Honestly not sure why a 20w50 would be required with a stock bottom end and a roller cam.
Seems like this engine builder is an "old school" guy with the thicker is better mentality.

Of course, we don't know all the modifications done to the engine besides the cam.
If the bearing clearances and pistons are all within oem type specs, I can't see running 20w50 as having any benefit.
Maybe a 5w40 or 0w40 with the more aggressive cam and extra power levels.
20w50 in an Indiana winter is not going to flow well.