Oil Weight for big cube street / strip Motor

What weight oil are you guys running in the big Hemi's and Wedges?

Valvoline VR10X30Wt
Works good, last a long time in my motors with vacuum pumps

Driven GP-1 synthetic blend 15-40. Very clingy oil.

15-40 delo 400. Change it often.

Rotella 15-40.... 540" wedge.

Depends on the clearances used when building the motor. Typically bigger clearances need heavier oil.

Exactly. Most new cars are running thin synthetics, but their bearing clearances are tighter. As an example, if your clearances are say .0025" on the mains and .002" on the rods, that's a little looser than most engines came from the factory, and you're okay running a medium weight oil, like 10w-30 or just 30w if you want something a little thicker. If you're engine was built loose like some racier engines are, say .003"-.0035" on the mains and .0025" on the rods, I would think you may want to run a heavier oil.

I also like the idea of running an oil with zinc, even on a roller cam motor that may not require it.

Penn Grade 20/50 in my 505 wedge . If you are sitting peak hour traffic for extended periods or extended highway use heavier oil may be a good thing . I do run a solid flat tappet cam . JMO .

Tex

VR1 20/50 mostly but I have used the 10/30 also. Its just not as accessible as the 20/50.

Weight will be determined by how much it's internally hemorrhaging (bearing clearance, lifter bore clearance, oil leakage through pushrods, etc) and oil temp. My new motor isn't particularly "oil efficient" plus with the block being filled the oil temps are on the high side.

So for me I had to put 20w-50 in it to get the oil pressure up where I liked it.

My piston to wall clearance on this one is tighter than previous, but most are about .003" for clearances. I typically run Brad Penn 20-50 and was wondering if I should switch to straight 50w? I burned #7 bearing last year again, so I do not want to do that again.

I would think you'd want to run (ideally) the thinest oil that will get you the pressure you need.

Idea here being:

1) any system leaks will bleed the pressure
2) thinner oil will make that bleed easier to happen: the thinner it is the easier it will be for it to escapte through any such path
3) of course you need volume to carry the heat away, so pressure isn't the only metric to watch, but as far as leaks go it's a darn good indicator

My stroker motor has:
1) 0.032 - 0.035" clearance on the MAINS
2) 0.020 - 0.023" clearnace on the RODS

I intend to run VR1 10W30, but if that nets me an uncomfortably low pressure I'll move up to 10W40, or 15W40.

Right now the crankcase is full of break-in oil (30), only 1 startup so far, but it was a steady 45-50 at idle and 75 at the initial start and about 2K RPM.

I found this DRIVEN reference chart to be pretty handy, take a look at the attachment.

540 street/strip Hemi, and 499" street/strip wedge. Used to run 20-50, then tried the 15-40, and then tried the 10-30.

Valvoline VR-1 10-30 is what has been in both engines the last few years. No synthetic, no additives. Both engines have SFT cams. Good hot pressure and no problems.

I use 20w50 VR1 and have used Brad Penn in the past.

I primarily use that weight it because we use nitrous and try to absorb the shock a little better.

I pulled it apart a couple of winters ago and was surprised at how well the bearings and the main caps looked! Almost no fretting on the caps and the bearings had virtually no wear.

This is all on a stock block with studs and spraying 250 shot.

I use 15W50 but also try to make sure the engine has some oil temperature in it before making passes. Thinner oils are better if you don't spend any time warming it up at the track for sure. The thicker and/or straight weight oils don't flow as well cold. In some other applications we've failed engines with heavier weights at cold ambient temps because while it has pressure, the oil isn't flowing to all of the appropriate bearing surfaces.

Yep, even after a brief warmup down the return road, the car will usually gain quite a bit due to all the oils and lube being warmed up after a pass.

On the oil pressure with warm, above 160 F or hot oil I like to see 10 Lbs. per thousand RPM, if it shifts at 6500 RPM I like to see 65+ Lbs. at that RPM.
I do trim or add spacers to the bypass spring as needed to achieve that, my old pump gas 400 stroker motor would idle at 850 RPM in gear and have from 18 to 22 Lbs oil pressure 60 lbs at 1500 RPM with 180F+ oil temps when revved up above that and gain another 5 lbs. above 3000 RPM

Driven XP3 in everything for me. Street car and racecars, all aluminum blocks.

I try to run as thin as possible. Thin enough to have 15-20psi at hot idle but also not have 100PSI through the traps once the oil cools off from the drive. My car is faster the cooler I can run it so I try to keep the engine as cool as possible. I normally try to hit the burnout box at 140 coolant temp, it slows down .1 if I hit the box at 160. Stupid naturally aspirated racing lol.

Castrol GTX Conventional 20W-50 in a 512".

Lucas 5/50 in my T/A 392, Lucas 20/50 in my 512 Charger

It's not big cube but,

With the 20w-50 pressure seemed rather high.

1150 idle, 49psi

2000rpm 70psi

7600rpm 78psi


With royal purple XPR 5w-30 it's now

1150 idle, 37psi

2000rpm 65psi

7600rpm 71psi

VR1 20/50 in the 580 (clearances are on the loose side now) I'll be running a lighter oil on the 655, likely 10/40.

Best off the shelf oil that works fine for me that doesn't break the bank is the RED LABEL 15W50 Advanced full synthetic "Nascar" oil that Walmart sells. 850 hp 502 that gets pounded at the track weekly.

6.00 a quart and plenty of zinc.

20-50 or Lucas plus 50,I don't keep it in very long .0028 rods .0032 mains on the 514 wedge on the street.

It hasn't been in the car yet, but I fired up the 572 on 10w30 Rotella conventional.

On the high side it was fine, hitting the bypass 68-70psi like the other big blocks with M63HV pumps I have had.

On the low side near 1000 rpm when it warmed up it was safe pressure, somewhere in the 20s, which I'm sure is actually fine but it does not give me a warm fuzzy feeling like
a solid 40-something does on the low end.

I may or may not adjust it to a different grade when I start driving it, but at least know it's within safe reasonable limits now.
Rods and mains were all between .0032 and .0033.

And I should probably get over that warm fuzzy feeling thing.

This probably doesn't help answer the original question at all but just trying to participate somewhat!

When the oil gets up to temp and after it shears its going to get even worse at idle. With the 15W50 I have around 40 at 150 degrees oil temp. Hot lapping going rounds it drops to 25 or so at 200 degrees. You are going to end up with something more than 30 weight most likely.

Rotella is good just to fire it and break it in, but it's not a good full time oil for performance engines anymore. No way would I run it full time in a serious engine.

575" street/strip hemi, aluminum block, .0035" main clearance, .0025"-.0028" rod clearance, 7.5 quarts of 20w50 Valvoline VR1. Been running it this way for years w/ no issues.
I ran Mobil One 15w50 synthetic until, for some reason, it became near impossible to find several years ago. I went to the VR1 then b/c it was readily available.

Agreed, I will probably end up with a 15-40 or 20w50. I have always liked a 30 for initial fire up of most anything, though.

The Rotella I used is an older and more desireable specification that is no longer available off the shelf. I have close to 20 gallons of it do plan to use it, eventually.

Have large quantities of SAE30 straight weight, also older spec that nobody I know had problems with, to try out eventually.

It's big CI but is a low compression pump gas street engine, and beyond that pretty sure nobody besides me would consider it "serious" for no other reason than I built it myself.

This thread clearly demonstrates (again) that there are many, many modern oils that will satisfy the needs of our engines.

Obviously, some engines have different needs than other engines; wider or tighter clearances, turbos, primarily track use, etc. But the OP is asking about a specific application; his street/strip big inch Mopar. He does not need an overly expensive, difficult to obtain, or exotic oil for his engine. Many members on here prove that every day.

And for his application, why would the OP want any weight heavier than the guidelines that many of us successfully use in this application, which is; At least 15lbs at hot idle and at least 10lbs for every 1000RPM till about 60LBS max. Now, those are guidelines. Not set in stone. But, without some special oiling needs, what advantage would more pressure or a heavier weight oil provide the OP?

Now, it would be prudent for the OP to experiment with the weights to find the right one. Maybe start with a heavier weight like 20w50 or 15w40 and if everything looks good, try a 10w40, and then if all is good, 10w30 or a straight 30. That's the way I have done it several times and have ended up with 10w30 in both of my 500+ inch street/strip wedge and Hemi. They usually hold 20lbs or so at hot idle and usually hit 60lbs or so by 3,500. Been running them that way for years.

I have used 20W50 I have noticed my bronze gear breaks down fast and I believe the heavy weight if a culprit

i like and use Valvoline VR10x30WT in my race motors
No issues ever, even in my last 15.1to1 comp. ratio 517 C.I. bracket motor with a solid roller cam and lifters shifting it at 7300 RPM and crossing in the 1/8 mile around 6500 RPM, 7300 RPM in the 1/4 mile
That car ran 5.50 at 125 MPH in the 1/8 mile, 8.80 at 150. MPH in the 1/4 mile with out maxing it out

Well, as mentioned, many different combo's with many different oils but fairly similar weights. We find the Penn Grade 20-50 to be a very good oil, and based on the responses, probably about the right weights for us. I do like the straight 30wt idea, I was considering straight 50wt when I wrote this and it seems no one went that far, and in a Steve Morris SMX vid, I caught him saying they run straight 70wt in the SMX due to them running methanol and I thought maybe I should be running a straight one weight oil like 50wt. ......But none of you suggested anything that heavy.

But, in the Hemi, my issue, is probably more of a volume issue. Which brings me to my next question about cam bearings. I see Steve Morris running 55mm-65mm roller cam bearings on all his street engines and no oil feed holes, only splash oil....

So I do not have a raised cam block, but is that somthing I could do in the next tear down? Block off the oil feed holes for the cam bearings and go roller bearings? I never really thought you could run those on the street, but I am learning more and more about these high end engines, and what makes them live where traditional tech may not. I also know many Mopar builders won't build one of these without bushing the lifter bores....Another area I have not gone into...

What say you guys with after market blocks?

The low deck 512 in my Duster had roller cam bearings in it. It was built as a street engine and I never had any issues with the roller bearings. It changes the oiling for the top end so you have to sort that out. In the 512 we just drilled a connection between the main gallery and the rocker arm oiling feed.

I also run 55MM roller cam bearings in my 528 Hemi on the street with no issues. Yes, with modified oiling.

My KB block has no lifter oil galleys...splash/drainback oiling only. Possibly one reason my engine has never had any oiling issues even w/ only 7.5 quarts in the pan?
Mine still has typical cam bearings.
If you're running solid lifters and not pushrod oiling, no reason not to bush the lifter bores?

These are the kinds of things I should know about before building one of these....Now I am starting to see where my build might have gone off track and why others work so well.

Either way, the updates I did this year should work. You do not have to do this with a 800hp wedge engine, but god help you, if you want a big Hemi....

So let me ask this, on a Callies standard cam position block, can I bore it for a 55mm roller cam bearings and plug off the feed holes?

You mean sort of like this? Looks like they have been doing it for awhile now.

Was checking out a pile of used up $uper $tock blocks and they all had it done, but no idea on the cam dimension or oil feed situation.

The blocks did have R@y B@rton logo stamps on them if that helps at all.

Seems like a must do....

I may be wrong here, I'm certainly no Ray Barton, but the roller cam bearings in those blocks are for friction reduction due to insane spring pressures (and larger cam cores) moreso than oiling. Taking oil away from the lifters where it isn't really needed is more beneficial in your case than having roller bearings.

Mine runs .0030"/.0027" clearance. Its run a 50/50 mix of JR1 5w20/ 5w30 for yers. Pressure runs 50@idle/80@7000. Oil temp is normally around 150 degrees. Same babbit cam bearings for over 950 passes. Springs are 310/805 psi
Doug

Yes exactly....For me, its a volume issue. I have been killing #7 & #8 bearings for years when they starve for oil....Wondering what other folks due differently. Obviously, an accumulator might be in order as well. So roller cam bearings and maybe sleeved lifter bores sounds like what I have been missing.

Maybe a better oil pump or and more oil volume in the oil pan

He's not lacking oil in the pan. I think he runs a 10-12 quart pan already. I think he runs the good Milodon external pickup style pump also.

Going to run 13 in the pan after we tested the oil height at 12, we still had room....

Driven GP-1 10/30. 508 BB 650HP and agree with RICRAW very clingy oil. I used to run the Valvoline VR1 10/30 and wasn't unhappy with that but really like the GP-1. Check out Lake Speed's videos on YouTube. some good info there.

At this point, if you had a 55 gallon drum for an oil pan, it wouldn't matter. I don't think the amount of oil you have in that motor is gonna matter...it's where the oil is going (or isn't going) that's the issue.

I run 5W20Wt Valvoline petroleum base oil in my hot street cars, I've seen 12 HP gain going from 30Wt to 5W20Wt with the same oil temps
Oil does two things for our motors, it lubricates and cools, look at all the current production cars running really thin synthetic oils and living

I think it all depends on your engine. My 426 hemi solid roller 7-quart pan and melling HV pump has more than enough pressure with 10w-30 mobil 1.

With my 55MM roller cam bearing cam. I run Penn Grade 10W30 with a Melling high volume oil pump that I took apart clearanced, ported and polished. Also run bronze bushed lifter bushings with push rod oiling and the RBRE rocker system that has built in spray bars. Also a 10 quart Milodon flat bottom top fuel/funny car oil pan with Milodon external pick up. and a 3 quart Accusump (just in case). No issues on the street with hundreds of miles or strip.

"I have been killing #7 & #8 bearings for years when they starve for oil"

In the interest of not being totally useless, thought I should mention during the WP/MP/Royal Oak boring era I did replace two iron blocks because the drill bit
for the main oil feed broke through the side of the main structure.

This type of defect would create the type of pinhole internal leak that could
cause a similar problem.

At the time, the oil feed hole was 5/16", which is pretty huge given the lack of material in the area of the main structure above the crank, where the hole passes through.
I never found out whether the hole was to print, or a world famous engine builder's idea.

It's not hard to repair with a tube pressed in..... but a messy job to confidently find it.... as the whole thing has to be assembled, pressurized, and viewed with the oil pan off, to look for leaks where there shouldn't be.

Might not need exotic parts or machine work, might be something wrong with the block

OK, back under my rock I go.