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Whats The Best Way Of Running In A New Engine Or A Rebuilt Engine

Italiazr1

By Italiazr1,
in Engines & Forced Induction

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SECURITY Grand Master

SECURITY

Posted
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keep the revs under 4k, and as you take off a standing start, accelerate a bit quick (not too quick) to around 30km/h so the rings bed in properly before the 1000km or 1500km is up.

also, try not to hold it at a constant rev, i.e. highway driving.

evil_weevil Grand Master

evil_weevil

Posted
Posted

dont sit in the same gear all the time at same speed

i.e. sit in 2nd at 50, sit in 4th at 50 - keep changing gears but not giving it a boot full

sinistaGTR Grand Master

sinistaGTR

Posted
Posted

yeh take it easy for the first 500kms then slowly increase your revs and boost (well keep this at 7psi). Make sure you dont just drive at the one speed either vary it upto 80kms/hr then once you hit bout 750kms start to increase you top speed aswell.

Italiazr1 Proficient

Italiazr1

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ok i will do my best to drive it like that then

what about boost levels mine will only kick in at like 4000 anyway so do i drive it off boost untill its run in?

or do i give it a litlle say to like 5000 every now ang again??

Faid Collaborator

Faid

Posted
Posted

Baby the car for the firt 100-200 km, changing early before boost. after that change enigne oil and filter, might wanna buy a filter magnet to trap shavings incase there are some. for the 200-500 km bring the car up to revs a little quiker then u used to but dont fang the car into boost. at 500 km change the oil and filter again. after this drive till about 80-90 km/h in the 5th gear. and when the enigne is at operating temps and you see a free pass, gear down hard and give her evrything she's got pull about 2 gears on full song after that decellarate and take you 80km/h grandpa drive, dont fang it too often, continue till 1000km but keep the boost low at about 8-9psi. at the 1000km mark youll be changing oil and filter for the last time now its time for the power run in, get it tuned for full power and your desired boost level, and now where the oppertunity presents itself give her all she has, when you overtake dont hesitate to bring her on full song, continue to about 1500 kms and your done with runnin in the engine. the frequent oil changes i do because the micro metal shavings that are normal to exist in a new-rebuilt engine have been known to stuff up bearings. this procedure has worked for me till now and ive run in 2 RB's and 10-12 haulpack engines

R31Nismoid Grand Master

R31Nismoid

Posted
Posted

Anthony.

Just bed the rings in on the dyno (the tuner/motor builder will know what to do)

Then tune it up. Simple as that.

IMO based on the countless motors ive seen done this way, "running in" a motor is frankly a load of crap. :)

If the motor is built right, just get straight up it. All the RB26/25's you'll see running around any of the track days are all done like this, all run perfectly fine.

Thats the true test.

45ULT Rising Star

45ULT

Posted
Posted

yeah the main reason for running in an engine is to make sure the new rings bed into the honed cylinder walls properly. so basicly by varying the speed at which the engine runs places different loads on the rings compared to just sitting at one speed with not much load as this will glaze ur cylinders. so if ur really keen take it for a mountain run but still keep the revs to around max 4 grand or so. this loads up the rings nicely as ur constantly on and off the throttle as well as loading and un loading the rings.

Simon-S14 Grand Master

Simon-S14

Posted
Posted

ffs, the people who say baby it for the first 200 kms or so have no clue, this is the most crucial period for the rings to bed in, you risk glazing the bores or not getting a propper seal if you dont load up the motor straight away, likewise you should avoid idling and sitting on constant RPM.

best way to run the motor in is to use stock boost settings, and drive it hard through hills, that way the motor see's a varying rev and load range. If the motor breaks during this period, its a shit rebuild :)

WPN-O33 Proficient

WPN-O33

Posted
Posted
Anthony.

Just bed the rings in on the dyno (the tuner/motor builder will know what to do)

Then tune it up. Simple as that.

IMO based on the countless motors ive seen done this way, "running in" a motor is frankly a load of crap. :)

If the motor is built right, just get straight up it. All the RB26/25's you'll see running around any of the track days are all done like this, all run perfectly fine.

Thats the true test.

+1

discopotato03 Grand Master

discopotato03

Posted
Posted

Just bit of load at low/med revs to get gas pressure behind the rings so they run a bit more tension against the bores to bed them in . No rocket science , I like SK's idea of using a cheap garden variety Castrol oil without the friction modifiers to help it along .

Thrashers be warned , because everything has been apart there will always be a slight chance something may leak and if an oil/water hose connection goes in a big way its the expensive engine that may need another rebuild . Also if some mechanical thing works loose you may not hear it before it goes bang at high revs . Oopsh .

Your engine - your money - your call .

Cheers A .

SECURITY Grand Master

SECURITY

Posted
Posted

just to warn you guys who think thrashing is the way to go:

i spent 8k rebuilding my m3. the mechanic was a firm believer of the 'tune it on the dyno' theory.

so i was thrashing it over the weekend and it was back in the shop 2 days later from a spun bearing (as all bearings were replaced).

the guy who built it has to fork out for another rebuild.

he then told me to baby it for the next 1k after i got it back.

its not just the rings that need to be bedded in. its the bearings too.

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