Oil for engine break in?

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So a new gm goodwrench tbi engine is about to be installed but the manual that came with the engine says nothing about breaking it in. I found a break in procedure from gm for there 290hp crate engine. I am going to do that break in procedure on this tbi engine. The break in procedure states not to use synthetic oil for break in just a standard non synthetic 10w30. I was going to use delo 10w30 xle but i noticed its a synthetic blend. Is that oil ok to use or should i just use pyb 10w30 or something? i was going to use the delo because the voa indicate a higher amount of zddp that would be good for break in.
 
Drive to parts store. Look on shelf for oil that says break in. When I was a gearhead we always used comp cams bespoke break in oil. No failures ever.
 
If its a flat tappet cam i'd use delo, rotella, some high zinc oil. If roller cam i'd not worry too much. I don't see why you could not use syn, but its a waste. I'd change the oil after it ran 20 minutes to and hour, and dumping syn that early is a waste of money.

Btw if it is a flat tappet cam, don't let it idle, keep it above 2000rpm for 20 minutes or so varying the rpm.
 
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It is a flat tappet engine. The motor is going in my dads truck so im trying to tell him what to buy over the phone.
 
You have one shot and only one at breaking that cam in don't skimp on using a dedicated break in oil.
If the engine uses a distributor or has a plug in the distributor hole use a dummy shaft and electric drill to fill the filter and bring the oil pressure up prior to cranking.

Vacuum fill the cooling system and set the timing as close as possible so you can bring the RPM up to 2000-2500 right after she fires and has full oil pressure. Run it for 20 minutes then dump the oil and refill with another load of break in oil leaving the filter in place.
Run the engine for an hour at varying RPM (you can drive it) keeping it off idle as much as possible then change the oil and filter, use high zinc content dino of the first 3K before going to synthetic.

Run an oil with at least 1000 ppm zinc 1200 would be ideal.

https://www.summitracing.com/search/product-line/joe-gibbs-driven-br-break-in-motor-oil

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Many cam jobs are ruined by cranking the engine excessively with no start.

That's where you will love a modern engine with no distributor. Once you get everything hooked up correctly it will start immediately with little cranking.

Liberal use of assembly paste is all you got for the first few rotations...
 
Aren't the Goodwrench crate engines run a little to ensure that they work before shipping out? So they should have gotten lube throughout during that process and went thru the initial few minutes of break in. Should be pretty much plug and play. Only got one GM crate engine in the past, in 1999. Just dropped it in and drove it. Changed oil after about 8 hrs of initial operation and never had a problem with the engine. All it ever got was a conventional 10w30. Pickup didn't last all that much longer, but the engine was fine.
 
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That still depends upon SAE grade. The "ILSAC" grades, which are 0w-30, 5w-30, and 10w-30 have to follow the lower phosphorus limits if CK-4/SN. That doesn't apply to the higher grades. I just went through a stack of API appendices, ballot results, and position papers from oil companies to the API to get some handle on that, since they don't have one definitive document on the matter, quite like they did to describe the old loophole.

Of course, none of this prevents an oil company from making a low phosphorus 15w-40, be it CK-4, CK-4/SN, or completely uncertified.
 
Since flat cam break in can be risky, I would look into Brad Penn break in oil. It has extra ZDDP, is conventional, and has only enough detergent to be driven 500 miles.

Royal Purple also makes a non-synthetic break in oil with similar properties.

Joe Gibbs also has something similar.

You should be able to get one of those oils at your local speed parts shop.
 
Motorcycle oil has a lot of zinc, like 1700ppm or so. I have not tried it but i see no reason you could not use that as a break-in oil. Not cost effective, except against the cost of beak-in oil.
 
Built a bunch of flat tappet motors over the years including some with serious cams. Have one in the shop right now (built 283) and have a BBC waiting in the wings. Just to make sure my thinking was/is in line with the hot motor crowd, I ran a poll on oil used by serious engine guys at Chevelles.com. Some of these guys are in the 8's with steel bodies and roll-up windows.

VR-1 was number one by 2:1 over number two (Mobil1). Now the poll did not discriminate between flat tappets and roller motors. But these guys are not using OEM valve springs. Some have open spring pressures running over 700 #.

http://www.chevelles.com/forums/13-performance/831521-what-oil-do-you-use.html

Take you pick of any of the top polled oils. But, hardly anyone in that crowd uses a break-in oil that has a "tweaked" formula. Most just break in on what they run. Some will do three changes on VR-1 and the switch to synthetic.

And the HDEO's used all have a slug of Grp III which is OK to advertise as "Synthetic" in the USA, but won't pass muster in Europe as a real synthetic. So HDEO's are basically just fancy Dino oils and work just fine
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RP stuff seems to have some issues for some people including RAT on his blog. You can do a search on Chevelles.com about engine break-in and you will have a good hours reading on flat tappet failures and what they did that let it happens. Comp Cams break-in oil is listed in those threads as a cause, or at least a contributing factor. Can't remember if RP was/is mentioned ...

My actual preferred break-in oil is Delo400 15W-30 SD (Severe Duty) which I have at least 16 gallons just waiting for new motor break-ins.

The trick in the old days for all GM crate motors was to add a can of GM EOS to standard motor oil like say Chevron Supreme or something. I dunno if EOS is still available (?), but if so, that is the tried and true GM break-in chemistry. It has worked well on tens of thousands of crate engines up to ZZ
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Originally Posted By: BrocLuno
And the HDEO's used all have a slug of Grp III which is OK to advertise as "Synthetic" in the USA, but won't pass muster in Europe as a real synthetic. So HDEO's are basically just fancy Dino oils and work just fine
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It passes muster as "Synthetic" in any country in the world.
 
Originally Posted By: BrocLuno
RP stuff seems to have some issues for some people including RAT on his blog. You can do a search on Chevelles.com about engine break-in and you will have a good hours reading on flat tappet failures and what they did that let it happens. Comp Cams break-in oil is listed in those threads as a cause, or at least a contributing factor. Can't remember if RP was/is mentioned ...

Couldn't be that he's throwing a red herring out to his competition/non-customers, right?

Similarly, Comp Cams likes cam failures with their own break in lube because they just enjoy processing warranty claims.
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Yes, EOS is still available, at least up here. I saw it on the shelf last week at a parts store that sells a whack of AC Delco stuff. I haven't tried it on a one armed bandit, though.
 
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