418W Oil Recommendation

[alan_mac]

I have a 351W motor that is stroked to 418. Forged rotating assembly with a billet roller cam. It has .0025 to .003 main bearing clearances and .0024-.0027 rod bearing clearances. These clearances are a bit larger since it is a street / strip race prepped motor. The motor has a Mellings HV oil pump. The engine consumes little to no oil. Its in a classic car that only gets 500-1500 miles/yr. Oil changes 1 time per year when going to sleep for the rainy season. I have always (8years) used Royal Purple (10w40, weight I think) with a Wiks filter. With RP my warm idle pressure was always around 18-22psi and would ramp progressively to 50psi when off idle. I recently changed to Mobile 1 (5w30) because it was on a huge sale at costco. Now my oil pressure is at 12psi at idle (850 rpm) It ramps up the same as before to 50psi. I use a Autometer electric oil pressure gauge, but see no reason to believe it isn't accurate. My questions to you Oil Experts is: 1) is 12psi idle pressure enough with full synthetic oil? 2) what weight oil should I use? (5W40 comes to mind). What brand of full synthectic do you recommend? (Castol Edge, M1, RP come to mind). Your reasons why would be great to understand. I enjoy reading this forum. Regards, Alan

 

[CarbonSteel]

Forget the oil; where are the pictures?

What about Rotella T6 (5W-40) if a synthetic is what you are after? Obviously, you could go Mobil 1 in 0W-40 or even 15W-50 (if the upper end of the viscosity is the concern).

 

[dave1251]

Your 12 psi at idle sounds fine. But with your low miles and annual oil change synthetic oils are a waste of money. I do not recommend any specific brand because each major brand performs about 99.9999999999% the same in real world applications although I have my personal preferences.

What are your driving habits on this garage queen?

 

[skellyman]

So you went from 18-22 at idle to 12 psi , most of what your seeing is from moving from a 10w to a 5w , really I don't see a huge problem , though if your still concerned just move back to a 10w syn oil.
Mobil has some great products an the UOA threads have a lot of UOA's shown there.

 

[CATERHAM]

Originally Posted By: skellyman
So you went from 18-22 at idle to 12 psi , most of what your seeing is from moving from a 10w to a 5w , really I don't see a huge problem , though if your still concerned just move back to a 10w syn oil.

Yes what you're seeing is the effect of the higher VI 5W-30 oil but I wouldn't go back to a 10W oil under any circumstances.
Your OP sounds fine but if you wanted to increase it a bit just add a quart of M1 0W-40. This will increase your hot OP somewhat while having a negligible affect on you cold OP.

 

[alan_mac]

Here is what the motor is in.

Interesting suggestion to use a qt of 0w40 to boost the idle oil pressure up a tad. I think its a good idea worth trying.

 

[OVERKILL]

I'd use M1 0w-40 in the engine, as that is my choice for the Windsor engines. It'll bring up your idle oil pressure a little (I think 12psi is too low for a Windsor, mine and those of my Mustang buddies are usually over 30psi hot at idle) and will give you good cold start performance, solid anti-wear protection and is in general just an excellent all around lubricant.

 

[DragRace]

Originally Posted By: alan_mac
I have a 351W motor that is stroked to 418. Forged rotating assembly with a billet roller cam. It has .0025 to .003 main bearing clearances and .0024-.0027 rod bearing clearances. These clearances are a bit larger since it is a street / strip race prepped motor. The motor has a Mellings HV oil pump. The engine consumes little to no oil. Its in a classic car that only gets 500-1500 miles/yr. Oil changes 1 time per year when going to sleep for the rainy season. I have always (8years) used Royal Purple (10w40, weight I think) with a Wiks filter. With RP my warm idle pressure was always around 18-22psi and would ramp progressively to 50psi when off idle. I recently changed to Mobile 1 (5w30) because it was on a huge sale at costco. Now my oil pressure is at 12psi at idle (850 rpm) It ramps up the same as before to 50psi. I use a Autometer electric oil pressure gauge, but see no reason to believe it isn't accurate. My questions to you Oil Experts is: 1) is 12psi idle pressure enough with full synthetic oil? 2) what weight oil should I use? (5W40 comes to mind). What brand of full synthectic do you recommend? (Castol Edge, M1, RP come to mind). Your reasons why would be great to understand. I enjoy reading this forum. Regards, Alan


Amsoil dominator oil is what personally I'd use.

Quote:
12psi idle pressure enough


Nope,I wouldnt be happy with that low of oil pressure myself.I'd be trying a different filter / oil combination for sure.


Awsome car and combo btw!

 

[alan_mac]

Thanks for the suggestions, I try M1 0W40 to improve my happy factor

I do feel wasteful dumping 8 quarts of brand new oil.

 

[alan_mac]

I can reuse the oil in our 2001 trooper that barely ever gets used

 

[alan_mac]

I spoke to the Mobile 1 Technical Expert. His comments were: 1) 12 psi hot oil pressure for a 351W is fine if there isn't an increase of valve train noise. 2) with a 351w they like the hot oil pressure at ideally 22 psi. 3) 0W40 would be a good choice for me to increase the pressure. Alan

 

[OVERKILL]

Originally Posted By: alan_mac
I spoke to the Mobile 1 Technical Expert. His comments were: 1) 12 psi hot oil pressure for a 351W is fine if there isn't an increase of valve train noise. 2) with a 351w they like the hot oil pressure at ideally 22 psi. 3) 0W40 would be a good choice for me to increase the pressure. Alan


Sounds about right

As I said in my earlier post, I like to see them above 30 hot at idle, but that's with stock clearances.

 

[A_Harman]

With the loose bearing clearances, you should be running a 40-weight. M1 10w40 High Mileage would be my suggestion, as it's a little thicker than M1 0w40. From your first post, it looks like RP 10w40 was giving you about the correct oil pressure profile from idle to high rpm, so you could probably go back to RP, although I prefer M1. I've seen too many cases of UOA's on BITOG of RP oils shearing significantly to be comfortable with their 10w40. But if your engine is maintaining good oil pressure over the life of the oil, RP is probably OK for a 1500 mile interval. (As you have been demonstrating for the last 8 years!)

Or you couldn't go very wrong with Rotella T6.

 

[alan_mac]

So is the HTHS Viscosity test a good indicator to use for higher oil pressure when hot?
M1 0W40 HTHS Viscosity, 3.8
M1 10W40 HTHS Viscosity, 3.9 High mileage

What is in the high mileage oil that makes it different than the advanced fuel economy grade? Anything particularly good or bad about the HM additives?

 

[A_Harman]

Yes, the HTHS viscosity is the number to look at to compare how different oils will behave when they are being sheared in a bearing at high speed and high temperature. It ultimately indicates how thick the oil film will be under high stress conditions.

I don't know that much about the specifics of how the oils are formulated. Since your engine has low miles on it since the rebuild, there is no inherent reason to use the High Mileage oil. I have had good results running M1 HM in my Camaro, where it decreased oil consumption by ~25% compared to regular M1.

 

[tinman11]

Built a similar engine for my 1969 mach1(410 windsor) billet roller,.0027-.0029 mains(3.0" mains),.0021-.0022 rods(2.1 rod journal).Engine builder says to use 10w30 for break in-flush,
2 quick oil and filter(w/magnet)changes about a hour each.Then run what ever 10w30 oil I want.
Was wondering if m1 0w40 would be a good choice in place of a 10w30? Never see winter,temps would be lows 40s in spring-fall and highs 90s mid summer.If m1 0w40 isn't a good choice will probably stick with brad penn grade1 semi-synth 10w30. I keep a stash of m1 0w40 for my polaris atv for it would be convenient.Any suggestions?

 

[Shannow]

A Harman is on the right track with bearing clearances in the .003 range.