I bought a gm crate lt1 motor from a chevy dealer. 4 Bolt main. Swapped everything over. Intake mani, all accesories etc.. Have about 500 miles on the current motor with no problems. Just changed the oil and didnt notice any metal flakes or anything out of the ordinary. I've been keeping it under 3000rpm. I was planning on this:
500 miles change oil
at 1000 miles change oil again
then after 1000 miles change it again and switch to synthetic.
I was gonna go 5000 miles before bringing it aboe 3k but some told me thats to much. So im lost as what to do. I searched and everyone has break ins for rebuilt motors Not one supplied from and built by GM. Any help? thanks

 

waiting 5000 seems a bit long to get on it. i personally would leave the non-synthetic oil to get on it after 1000 but not past 2500. just my opinion though and you know what they say about those.

 

After 1000 miles you should be good to go. Most might even argue 500 is plenty. I'll compromise and say 750.

 

i have just over 1600 on my 383 and its seen 7k a couple times already. my engine builder said to drive it like you would anything else, i would assume they break in their engines on their dyno but i'm not sure.

 

Opinions vary so much on this subject..... One on my friend's philosophy is to run it hard the first five minutes.. If it doesnt break, then its OK...

Myself, I use the 500 mile rule... Drive normal, no high revs, etc.. As for oil, a dino 10w30.. After that, synthetic, ***** to the wall..... If it breaks then, start over...

 

Just one notch below "Drive it like ya' stole it".

 

Where did you get your crate motor from and how much was it... if you dont mind me asking. My 95 z28 has 185000 miles and i've been debating whether or not to buy a crate from somewhere or have mine rebuilt. im not sure which is the best way 2 go.

 

Alright thanks fellas. since i already did 500 miles of no revs over 3k. the next 500 miles ill gradually bring the revs up and up. and at 1k miles 1 step short of drive it like you stole it. lol

As far as the crate motor I got it from a group deal on here. Its no longer goin on. But the proce was $1795 plus shipping. I have no regret going this route besides my clutch. I believe i got sent the wrong one.

 

If you baby it for 5000 miles, the rings may never seat. Since you already have 500 miles on it, you should be getting much harder on it. Don't wait any longer.

 

Agreed, the rings require a certain amount of pressure to fully seat. I usually do a an easy 20 miles or so to make sure there are no issues or leaks and then drive it like I normally would. Make sure to vary the rpm if you go for longer drives, street driving is the best for this, not so much highway.

 

So even with 500 miles it would be alright to bring it up to 4-5k without a problem? My normal driving i usually redline a few gears for enjoyment purposes. Plus i have a new clutch that was put it which is i guess broken in already. I put 500 miles on the motor in about 3 days just driving around. It varied highway and stop an go.

 

i agree.

 

Yes you should be just fine goin up to 4-5k no problem. What I usually do when breaking in a motor is street driving in a lower gear then i would normally run, in stop and go conditions. This allows for a varience of rpms and the rings seat real quick. If you do happen to go on the highway just play around alittle by giving it alil throttle and then cutting back etc.

I also change the oil at 100 miles, 500 miles, and 1500. And cut open the oil filter to check for anything that doesn't look right. Some might consider this alil on the cautious side though

 

As many answers as there are people. I've always been of the "drive it like you stole it" group. Don't know how many time we've stayed up until O-dark-30 on a Friday morning, assembling a new engine, so we could race on the weekend. Also raced my buddies on the way home from the dealer in my new car/s, several times. Maybe I was just lucky, but never had a problem.

 

i just put a new motor in my 93 z, i let it idle in the driveway with some high revs and then drove it easy and eventually started doing high revs, only had about 1000 miles on it, did the first oil changed with semi syn. the oil was regular looking. It runs great but now im gonna put 2k and change it again and then its gonna be regular oil changes from there.