What's The Best Way To Break-in A New Engine ?

[huckleberry 0]

http://mototuneusa.com/break_in_secrets.htm

 

Look at that link, please someone tell me this is alls hite. There are lots of info on it too which I'd like to hear Dave's opinion about.

 

Tim

[Jay 1]

No this isn't s*ite, there was a huge discussion about this website and the topic on another forum I used to moderate. I know a couple of people who have tried the method suggested and contrary to common belief, their engines are fine. Whether or not they produce more power than a gently run in engine is impossible to say, as both engines were complete different spec both from each other and from what they were pre-rebuild.

 

Certainly if I was running in a new engine under warrantee (i.e. in a new car), I would try this method.

[findlay 0]

My mate had his 106 GTi rattling off the limiter virtually from day one and I have to say his car wiped the floor with my 106 (which in itself was a fast 106...) after 10k miles when my engine had done 20-25k

 

I'm tempted to do the same with the Mi when I get it back (kidding Bert )

[B1ack_Mi16 67]

I'm going for the hard running in method on my engine too.

 

For me the information on that page really make sence.

You need a fair amount of cylinder pressure to press the rings hard agains the cylinderwalls, and the rings need to be pressed hard against the cylinderwalls to break in properly.

[DrSeuss 0]

This has been discussed previously at length on this forum as well, not that web page but various methods of running in. I'm quite happy to believe the method outlined is the best method. Engines are made to higher tolerances and as such ragging them would help seal the rings and increase power.

[Alan_M 66 1 Cars]

This sort of coincides with something I was told a while ago, when I was getting my crank checked.

 

Apparently, find a steep hill, wack the car in fifth at the lowest possible revs and boot it up the hill. Do this several times........

 

Still unsure what i'm doing with mine, probably the above but I have the complication of running in some new cams at fast idle with no load to deal with before the engine see's anything like tarmac.

[fiji bob 0]

i thought piston rings needed different honing finishes depending on the ring material? wouldnt that change the way you run an engine in?

 

has anyone signed up to the site?

Edited March 13, 2005 by fiji bob

[JamesLumley 4]

From my own personal experiences with rebiult engines.

 

A series 1430 engine, (basically a very highly tuned mini engine with 142 bhp)

has been through various rebuilds in the last 4yrs. The first time I had it built up, it was run in very gently not exceeding certain revs for certain mileages.

ie 3000rpm for first 500 miles

4000rpm up to 1000 miles.

I didn't give it any abuse until it had done 1500 miles and it was'nt rolling roaded until it had done 3000 miles. It gave 136 bhp.

 

It ran fine for about another year and subsequently dropped a valve seat out of the head, which wrote off 4 forged pistons, race head, block - the full works.

 

When I had a new engine built, the builder (a different one) told me that the running in process was a load of crap. If it had'nt bedded in by 500 miles, it was never going to.

He said run the engine on the cheapest oil for the first 100 miles and give it some reasonable abuse. Once this had been done, change the oil for high quality, check tappets etc and away you go.

 

This engine has lasted for 2 years of daily abuse, I thrash the hell out of it right up to the redline in every gear and its never had any problems. When first rolling roaded after 600 odd miles, it gave 142bhp.

 

When I rebuilt my MI16 engine for the rally car last summer, we ran out of time before the event and the engine susequently had only done about 40 miles before the first stage. It had new pistons, rings, liners etc but had a completly standard spec. The first 10 mile stage was run on cheap £5 per gallon oil which was then changed for mobil 1 motorsport 0-40w.

It survived 90 miles of 7000 rpm+ in every gear in 90degree heat on a tarmac rally and when later rolling roaded showed 174bhp (runs on carbs)

 

I would be interested to hear what Dave Bakers preferred method as he must have much more experience. I will probably do something somewhere in between the above methods with the new engine that I am building.

[damien 22 1 Cars]

so what is the right way of running in a rebuilt engine?

 

ive been doing the 3000rpm for first 500 miles, 4000rpm up to 1000 miles, 5000rpm up to 1500 miles as when i asked this befor on here i was told this was the right way of doing it here - http://forum.205gtidrivers.com/index.php?s...2438&hl=running

[SPGTi 2]

I have always run new built engines fairly hard from the off and never had a problem. A hillclimb car that is running an XE vauxhall engine ran the engine in that way and after 2 seasons it still looked perfect on stripping down (uses same garage as me).

 

With the amount of miles I do it would take me years to run an engine in if I wanted to do a few 1000 miles before booting it.

 

Steve

[Butler 0]

There has been a similar debate on running in motorcycles which come with a strict running in period.

 

I think they concluding that you get more power, but the ultimate life of the engine was reduced.

 

They said if you you buy a new bike and only intend on keeping its few years then cain it.

[Beastie 1]

This debate will run forever as far as I can see I believe that it depends upon how tight you make the tolerances when you build the engine. If you are building for maximum power then the tolerances will be a little wider and running in hard should be considered. The sort of engines I build are historic and worth a fortune. They have to be built for long life and quietness as well as good power so the tolerances tend to be quite tight. My customers are most welcome to run these engines in hard. So long as they don't even think that I would entertain a guarantee on them if they did.

[fiji bob 0]

do you think theres merit in using lots of throttle at lowish revs but keeping the engine speed down?

[Galv 0]

I drove my 330CD pretty hard from new, after 6k I dyno'd it at 213 bhp. 9 bhp above std. and most people recon they don't reach full power until they have done alot more miles.

[Miles 331 1 Cars]

Well if you run the XU engine in Hard the big end bearing's will look like Andy's post about his sized engine, RUN and will last a few K if lucky which when these where new you heard stories about these engines not be very good and breaking which I think is why, Who runs in a brand new car?

[B1ack_Mi16 67]

Well if you run the XU engine in Hard the big end bearing's will look like Andy's post about his sized engine, RUN and will last a few K if lucky which when these where new you heard stories about these engines not be very good and breaking which I think is why, Who runs in a brand new car?

<{POST_SNAPBACK}>

 

Hm.. Did anyone ever find out what the problem with the XU big ends are then?

I'm going for BMW rod-bearings and 48mm journal on my new engine and really had planned to use it pretty hard from the first startup. On the other hand, I really can't afford to break the engine.. But whe should the big end fail on a newly built engine when driving it hard from the start? If the crank is polished and everything is done right, I can't see why it's more dangeroud to run a new engine hard than an old engine.

 

The Mi16 in my 405 has now passed 205000miles and still going strong, taken to the limiter almost at every drive. Approx twice a day..

[Miles 331 1 Cars]

It's the wipe speed of the Rod at a guess, The 2l is better as the stroke is shorter, I think the only way to get a good answer is to test 2 new engines built to the same spec, One run in the other run hard from new and the other over 1000miles,

My 406 has done 140k now and is driven very hard, Not sure how it was run in but I guess on the Motorway and is 100% sound

[Simes 248 2 Cars]

There has been a similar debate on running in motorcycles which come with a strict running in period.

I think they concluding that you get more power, but the ultimate life of the engine was reduced.

They said if you you buy a new bike and only intend on keeping its few years then cain it.

<{POST_SNAPBACK}>

 

True,

 

My old 2-stroke scooter lasted 30,000kms as I ran it in as stated, other folk didn't bother and although in standard form they had more power they tended not to last long at all.

 

Running in my 4-stroke nicely too.

[Butler 0]

I would run in a two stroke, definitely.

 

I also didn't think you needed to run in new cars. I didn't any of my company cars, but then who would

Edited March 15, 2005 by Butler

[phatgti 0]

My father runs them in hard but they are race engines.

last year he built an overbored 1.7 16v alfa boxer engine (1820cc or summin) with big cams and twin 48 webers, steel crank/rods etc...

 

We put it in the car, got it running, ran the new billet cams in for 20 minutes then immediately took it to the rolling road where he ran it up to and sometimes beyond 8500rpm, this engine made 258bhp and is quite simply awesome, reguarly wins his class (and some outright wins) in the SEMSEC track and race championship (mike watson).

 

I ran my Mi a few times to make sure she was good when i built her but then i took her onto the RR and ran it hard to the limiter, made good power (and i forgot to hone the liners too) so im in agreement with this method.

[alex205mi16 1]

i used mineral oil and used full throttle acceleration but not banging it off the limiter, just say to 4-5-5.5k rpm.. after a few miles, about 30ish i just changed oil to better quality stuff and used car as per norm, it must have been 80 odd miles before it got some serious action..

 

need to get it on the rollers

[efy2bjg 0]

It would seem to be the best of both worlds to run a new engine in gently and then change the rings and run it in hard. surely?

 

bit of an arse taking it apart again tho

Edited March 15, 2005 by efy2bjg

[Ahl 4]

Its interesting this.

My question would be, how do you apply this break-in to the 20min @ 2000rpm that a new camshaft is supposed to be run at?

[205_19_T 0]

Its interesting this.

My question would be, how do you apply this break-in to the 20min @ 2000rpm that a new camshaft is supposed to be run at?

<{POST_SNAPBACK}>

 

Not changing them at the same time

[Ahl 4]

Fair enough. Im just lazy!