Just got my long block back from the shop. It needs to be primed etc. still.

How do I break it in?

I was thinking of running it for 30 mins at 1800 rpm?

 

if you're gonna baby it all its life, just drive it easy for a while. if you're gonna race it, drive it easy for the first 20-30 miles maybe then start beatin on it!! That's how I do it and haven't had any problems from it!

 

I've been told that it's best to vary the rpms and decelerate in gear to get the rings to seat properly. I changed my oil after the first 50 miles to clean out any metal shavings. Use only dino oil for the first 1,000 miles.

 

There is the addage "break it in how you plan on driving it". I am a firm believer. I personally would drive 30 continous miles seeing all RPM, but never more than than 1/2 throttle. Come back change/inspect oil and filter. Do not run a synthetic oil for at least 1,000 miles. Everything needs to seal up.

 

I've been told by machinist and car people alike to go easy on it for the first 500 miles, change the oil and then have at it (this applies to all cars regardless of hp) . It makes since seeing that when you buy a new car they tell you not to accelerate hard for the first 500 miles or so. As for ther initial breakin I believe you are supposed to change the oil immediately after you have ran it in your driveway for 20 to 30 minutes because the assembly lube has a tendency to clog the oil filter.

 

yeah, lots of people say to run it 500 miles...doesn't mean that's the best or only way to do it. most race motors never see 500 miles... you don't build a race car engine and baby it for a while, you go see what it'll do right off the bat!

 

I picked up a case of 5w30 dino oil and a purolator oil filter to break it in. I'm going to do the 30 mins in the driveway before I drive it.

 

i didn't build it to baby it,but i also didn't build a 12,000$ engine to break it !
i JUST got mine started last saturday, held at 2000 rpms / let idle for 20 minutes or so, let it cool down completely and let it idle and get hot. did that a few times. i now have 95 miles on it and haven't taken it above 2800 rpms. its hard guys but i suggest not getting into it until 500 miles or so.

 

I'm not trying to be mean or anything. Honestly, just a question...how do you put $12,000 into an engine?? What all do you have in it? My dad and I built a 350 and swapped it into his s-10 for just over $500. That included buying headers for it and stuff, too.

 

no offense taken at all...quick example. u paid 500$ to build an engine, buy headers, and stuff...

here is my exhaust system.
ceramic coated hooker longtubes 698$ shipped
hooker off road y pipe 190
borla catback 700
o2 sims/gaskets/arp bolts 100

as you can see, thats about 1700$ worth of exhaust parts..building an engine is NOT cheap, alot of people on here can vouch for that!

then besides that i had alot of machine work done to the block, all forged lower end, heads/cam all bolt ons. still haven't touched the rear end..

 

maybe this is why they dont see 500 miles... ahh just kidding what do i know

 

I allways start it, get it running right , make sure everything is in place and not out of whack, change oil take it out and acclerate about 3/4 throttle from 30 to 60 mph several times let it cool back down, repeat , then drive it the way I want to, never had a problem.

 

There is no reason to sit there and let it rev at 1800 RPM for 20 minutes or any of that crap. That's for a flat-tappet cam and that's to break in those lifters.

If it's a roller-cam engine, everything I've read from various builders say "Let'er rip". Warm it up, drain the oil, and go beat on it to seat the rings.

 

lol...i didn't say my engine don't last 500 miles!

Ok, you're including your whole exhaust system in that....I can see more now. And the forged bottom end and all. I've always run stock cranks and everything, that's one place I save some money. Also, I do ceramic coating so I buy headers with cheapy paint or no paint and coat them myself when I want to. That's where I save a lot of money on exhaust and that I'll weld up my own exhaust system unless it's going to be a really tough one.

 

I've never waited more than 20 miles before I had at least one full throttle blast, and there is alot of people now that say this is the best way to get the rings to seat properly.