What is the best way to break in a new engine?



I have the ablity to use a dyno, should I do this or do the milage way? Any input would be appreciated.

is it brand new? if it is, take a 500 mile trip that should do the trick.

i was curious about this too.

i'm planning to get a rebuild done soon.



so what i'm curious about is...what is the proper break-in procedure for a TurboII rebuild?

redline it for about an hour in first gear on a highway.***



kevin.



*** - do not follow this advice, engine failure will follow.

As little boost asd possible if its a turbo car.



I ran wastegate spring boost which was 8PSI and did not go over 4K rpm for 400 miles then no more than 5K for the next 200 then 6K for the next 200. At 1000 miles I changed the oil and turned up the boost.



I tried to do as much around town driving as possible constantly varying the revs. A lond droning highway trip might do the job too but not the way I prefered to do it.

Jim, according to what i hear, you're right about constantly varying rpms. Most people say absolutely no boost, and i know a couple guys who stayed under 3k/3.5k.



but obviously yours hasnt blown up and is running strong so it worked for you.



Everyone has their own varyign opinions on the break-in thing so its hard to say "this is the exact way to do it"



kevin.

I know a lot of people tha tbreak their motors in with dyno runs...



There really isnt anything to break in (if you are reusing the bearings)

Im not reuseing the bearings! I think Ill just do the dyno break in! But then I still have the 500 miles of the centerforce clutch break in!



On the dyno, from what I have learned, is to do 1st gear 5k for 5 min, 2nd 5k for 10 min 3rd gear 5k for 20 min, 4th gear 6 k for 30 min, and 5th gear redline it acouple of times and youll be good to go!

i ve seen many broke in cool by idlling it up high about 2500 rpm and lettin it run and run and run. not revin past 3000 rpm 4 at least a thousand miles. a freshly rebuilt can b reved hi 4 100,000 mi + after being brokenin properly. THE LONGER U BREAK IT IN , THE LONGER IT WILL LAST. a fresh motor should NOT b reved hi, itll pop or die early. theyre expensive to build and eazy to to blow when they are new.

Staying below 4K rpm's really doesnt lend to much boost. I just drove it really easy for the first 1000 miles. Do any of you guys remember all the pictures I took taking small trips everywhere with my car trying to get the 1000 miles on the engine asap.



These guidelines were per Pettit Racing BTW this was after he street ported my engine and installed 3MM apex seals.



I guess its whatever you feel comfortable with.