I just got done building a new engine (350 with pretty big cam i guess, and all the new stuff heads carb intake etc) How long do you think I should wait untill you think i can start hammering hondas etc? Oh and its not a hardcore drag car...just a little street racing here and there...

 

if its completely new, like rings and bearings, personally i'd take it easy for a couple hundred miles to break it in. try and keep the rpms down, then i'd say you could go kick some ***.

 

Yeah its completely new, Ive heard many many different statements on which how long I should wait, Ive heard from a couple hundred, up to 5 thousand miles? lol I don't know which one to believe.

 

theres no point in waiting longer than you would go between oil changes, by that point the oils done all it can do to protect and its time for more

 

Wow, you know Im angry I didn't think of that. I totally forgot about that one. Thanks for the tip.

 

I've heard that 500 miles is usually a pretty safe bet. After that point you can open it up a little and start having fun. I don't think you need to wait 3,000 miles, that seems a bit unnecessary.

 

drive it for about 500 miles real easy, after those miles are up, change the oil and check for metal shavings and such. Drive it easy for a few hundred after that and you should be good to go.

 

I have always heard go for 100 miles then change the oil. Go another 500 to break it in then let it have it. You will hear a lot of different answers to this. Just do what you are comfortable with.

 

at least from 500 thru 800 miles before start doing high rpm's on that engine and the first oil change is at 100 miles the second from 500 to 600 and then start eating imports

 

drive it like ya stole it...by drivin it how u normally will the engine will break in to the tolerances itll be use to everyday. my friends 350z is a whole .5 second quicker then everyother stock 350z because he broke it in this way.

 

we put my 383sbc on the engine dyno, broke in the cam for 20mins,changed the oil and started making pulls. ring are seated just fine =]

 

For a street/strip car:
Drive the **** out of it. If it breaks, you built it wrong.

For a daily driver:
Take it easy for 1000 miles, then drive the **** out of it.

 

very true... umm wait at least 500miles..

 

Do alot of city driving and try to stay off the hwy. I read it in one of these engine rebuild books I got.

It says don't keep the rpms at a constant speed for too long stop and go traffic is best for breaking it in. Leave your SPEED at home.

 

Break In Secrets--How To Break In New Motorcycle and Car Engines For More Power

 

A lot of things determine when you can "run" a new engine hard. Is this engine a roller set-up? Is it fuel injected? Is it flat tappet?

Roller motors don't need the same break in as a flat tappet one. Roller motors can basically be flogged right out of the gate. New cars don;t even have break in procedures listed in the manuals anymore. Better manufacturing methods and design improvements don't necessitate it. However, since you still have an old Gen I set-up (even if it is roller) you will want to go easy for 500 miles, change the oil and flog away. A flat tappet set-up needs a little longer to establish the wear patterns in the lifters, and cam.