race engine break-in

[ShadowBolt]

There is so much crap on the net about this that I don't know what to believe. I hope to install the new (rebuilt shortblock) next weekend. I can't see just going to MSRH and running full out. Rings are the only thing that really need breaking in. Ideas?

JJ

[GlennCMC70]

i ran mine on a Friday test day for about 3 sessions then loaded it up and took it home and changed the oil then took it to the dyno and made about 6 pulls. ran it easy in sat morning practice and qual and short shifted it for the races that day. i didnt baby it other than just short shifting. get as many cold to 180-200 degree heat cycles on it as you can before you run it on track.

the 98 Camaro i had was broke in on the dyno. 26 miles of cyclic rpms and then we made about 100+ full throdle pulls over the next two days dyno tuning it. the thing ran like a top for many years.

the fact that it seems everyone does it different tells me there is no real right way. i've always leaned towards "break it in like your gonna drive it".

[AI#97]

i've always leaned towards "break it in like your gonna drive it".

My engine builder answered this question with "heat cycle it to set the headgaskets 5 or 6 times, then retorque the head studs. Put a safe tune on it and beat the shit out of it. Change the oil filter after 20 minutes of running and change the oil/filter after about 2 hours of usage and continue to beat the shit out of it." This was on a motor that had a LOT of machine work and potential for shavings so you might not need to do the additional filter change...

[David Love AI27]

I asked this before and was given the same advice Glenn gave... as DD told me... "Run the shit out of it" and I did... no problems from the crate motor, YET :shock:

[BryanL]

What do engine builders do when they build one and immediately put it on the dyno. Some say once it reaches operating temp. its broken in. They break in the cam and bring it up to operating temps, check everything, and then full pull. My dad and I took a fresh motor to a dyno once, guy had it in his garage. Warmed it up and broke in the cam. Checked eveything and then a full pull.
If its going to break you would rather it be on the dyno. My rebuild I went from installing it at the house, running it some at home and then took it to the dyno. Ran it on the chassis dyno at varying RPM, checked oil, leaks, etc. Then made about 20 pulls. Been perfect ever since.
I say put it in and get it warm to a few times and vary the RPM's, then take it to the dyno and see what happens. Lot cheaper/easier to have a problem on a dyno close to your house rather than at the track.
I also agree with the oil changes and a magnetic plug to find out if you have any issues from the break in.
May also want to you regular oil instead of synthetic.

[GlennCMC70]

yes! new motor needs to be on dyno oil.

[Adam Ginsberg]

Make sure that whatever oil you put in the motor for break-in (and even afterwards) has ZINC for proper cam break in. Many oils have eliminated ZINC from their formulas, much to the detriment of us gearheads.

Do some googling.....