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Engine break in procedure

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sypherzero

15+ Year Contributor
461
7
Feb 14, 2008
Marion, North_Carolina
Hello everyone, first off, I know there are numerous threads on this, but I would like to narrow down the different opinions into something that more relates to my application.

I will be running a 4G63-t in my 95 GSX. Its going to be running ACL Tri-metal bearings (main and rod), not sure on piston rings (suggestions?), OEM head gasket, and will be running the stock T-25 on stock boost.

The head will be cleaned, and the block will be hot tanked and honed. 84k miles on the original 7 bolt. Just a few bolt-on as well. Dejon UICP, RRE LICP, 1g BOV, Injen intake, K&N open element filter, Megan O2 housing, DP, and custom 3" DP back.

So my question is, whats the best break in procedure? I want it to be fast, but I don't want to have to tear it back apart too often. I honestly don't want to take it apart again unless I get some forged internals, which will be a WHILE.

I've seen this link Break In Secrets--How To Break In New Motorcycle and Car Engines For More Power more than a few times. Anyone do it this way? Or any really successful personal break ins? Any help and suggestions will be greatly appreciated. Thanks guys/gals, Cj.
 
I have seen people have success and failure with both methods of break in. The baby it method and the drive it like you stole it method. I think the key thing to success is the machining, measuring, and cleanliness of the build. I tend to be a little on the baby it side at start and then build to more intermittent bursts of progressively harder runs. I think that article is a good one to follow. The part talking about the crosshatching being worn off before the rings set in kind of threw me. My 145k 4g63 still had the lines in it and held good compression. I talked with an old drag guy and he said good blocks that had alot of nickel in them would do that.
 
i've always been a fan of, break it in how your gonna run it.

if your going to run it hard, break it in hard, dont granny it untill 2K miles or whatever.

in my personal opinion, you need varying loads, rpms, etc to properly seat the rings and everything else in there place. only thing i make sure to do is change my oil frequently the first 2K miles.

changed at 200, 500, 1500, then normal from there on out. never had any problems with any of the motors i've rebuilt.
 
Warm the engine, let it reach normal operating temperature. That would be just under the halfway mark for dsms. Or if your running link/aftermarket temp gauge you can monitor it and weight until it reaches the temp of your thermostat.
 
You won't be disappointed. I've used that technique on 2 engines so far and still have perfect compression across the board. :D
Woot woot!
And common... it only makes sense ;)

Break it in slow - it'll be slow for life
Break it in fast - it'll kick your a$$ ;)
 
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So what break in method did you end up using? How is the motor so far?

I'm going to use the method in the link when I get the motor put together. But that will ###### be January of February when its finished, its kind of on hold for a while. I'll keep the thread updated though.
 
I bring mine up to temp and don't let them idle for about 20 minutes or so while I check all area's for leaks etc. I go out and drive under varying load conditions and even boost after a good warm up and drive. I broke my current motor in on 32lbs of boost and she is fine. It is just how I go about break-in's.
 
1.Use regular non synthetic oil 10w -30
2. Start car and hold RPMs at like 2grand until motor is up to operating temp.
3. Go for a drive and drive normal varying load, rpms and boost under 10psi. The key is to load the engine hard so say like 80% throttle in 4th gear at 45mph to get up to 10psi and then let off and do long full engine vacuum, this is what seats the rings.
4. After 10-15miles you are good to go, you can go WOT. Of course tuning is always a factor on a new build so you may want to not go full tilt until your tune is in check, but it is not uncommon for me to being running 30psi+ up to 7500rpm on a motor that is 20miles old.
5. After 200 miles change the filter and oil to 20W50 non synthetic. Your motor is ready to go.

Babying a motor does nothing, it's a wives tale.
 
I bring mine up to temp and don't let them idle for about 20 minutes or so while I check all area's for leaks etc. I go out and drive under varying load conditions and even boost after a good warm up and drive. I broke my current motor in on 32lbs of boost and she is fine. It is just how I go about break-in's.

This thread isn't that old.. so I'm reviving via a question: ragging on it off the hop, how ever do you get your VE correct enough not to run too lean in those high boost cells right off the hop on a totally new build all while trying to push the motor?
I suppose having someone watch the AFRs while you watch the road helps.. but even the stock VE table goes out the window when you've modified almost everything about fuel and air delivery.

Been looking for break-in oil but coming up short on suppliers here. Amazon through a complete third party has Lucas in a jug and also the additive version. Amsoil sells from their Canadian website in one quarts, making it over $70. That's about a buck fitty USD.
 
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I use the Lucas High Zinc break-in oil. After I let the motor get warm and look for leaks and whatnot. Once warm, I sit in the car and use the calculator to get global close, then do just as you said, go for a drive and have a second hand watch AFRs or the tune, one or the other. I have to do that a few times but my cars start right up, no FIAV, it runs and I walk away while they warm up. IDK what I do wrong or different but it works. Tuning the WOT then becomes the issue, if that is what you are getting at. Usually all the work goes out the window and I adjust global for that and readjust my idle to within +/- 5% Long term and Short term trims. It helps having my son watching and adjusting the tune as I ask. If it goes wonky, I have him put it back and we go a different direction. It's probably not right, but it does work for getting the new motors running and then get some assistance with WOT since it is usually too lean.
Sorry I'm not much help.
Lucas also sells straight 30 wt that I usually use on first startup, then move to the 20w50. Since we have "roller" cams, there is no camshaft breakin period, just seating the rings.
Marty

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Don't sell yourself short, Marty, it's a help. The wingman is definitely a good idea as the can adjust on-the-fly while you're engine braking those rings to seal :p
I've only properly had to break in one engine and I was on MAF at the time. It kind of makes me want to switch back just for the first 50km or so until I dump the break-in oil out. Get some data out of the MAF that way and still be safe.
I'll check a couple speed shops here in town, we don't have many, and see what they carry with respect to BI oils.
 
I use this along with breakin oil for domestic Flat Tappet pushrod motors. It helps keep the cam from going flat. It is also a good breakin additive for us too.

Rislone Hy-per Lube Zinc ZDDP Supplement - 11 oz. https://a.co/d/7CGcgOg
Or, I buy it buy the case.
 
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