Minimum Miles for Running in???

[Fazz]

Howdi All...

For those that have had rebuilds...

The question is what is the minimum miles for running in, or more lilely the minimum miles at correct acceleration.

My R is finally returning this week on Fri all going well... Trouble is, I've rolling road day on Sat! Tight or what!

So I may be driving all nite to run it in.

Now I've done a bit of research, and some say 1k miles but it seems 500-700 is completely acceptable, as long as done correctly.

Seems allowing pressure to get the rings to expand is the objective.

So into 4th/5th and up hill where possible just not revving too high in early stages.. thena gradual increase in revving...

All agree or disagree?

For those interested - check out this link. Interesting read...

http://www.mototuneusa.com/break_in_secrets.htm

Hard driving does become a feature which makes sense...

I will try run it in on rollers before rolling road but this is looking less likely an option.


So, how many miles have u done?
Do u agree with the above link?



Praying R finished for Thursday here! ( I'd have to do a 250mile round trip to collect and further 250mile to get to rolling road day so running in time there!)


Opinions wanted.


Cheers,
Fazz

 

[campbellju]

IMHO, forget the rolling road day and bed the car in properly.

The worst thing you can do to run in a new engine is to stick it on a motorway for 500 constant miles.

There are different opinons on how you should run an engine in but I don't think you'll get many arguments over not doing it that way.

This has come up before many times so I would recommend a search to form your own opinon as its your engine and the best person to ask is your engine builder as they are hopefully warranting their work.

Regarding the American link, people always come back to how hard is hard and how soft is soft? Everyone says you need to rev the engine hard for the first 15mins but my engine builder called hard 3-4Krpm, not redline full boost dyno run hard.

For the next 50/250/500/1000 mile markers, everyone has a different opinon on how "hard" the engine should be treated to ensure long term reliability.

I think Websnowbo used to do it for a living if you search on his name.

 

[campbellju]

To highlight my motorway point, I was advised by a few preofessionals to bed the engine in on the overun as well as under power. Whenever I came to a long staright or M'way, to avoid constant revs for periods, I would rev to around 3K, drop a gear and over run to 4.5K let revs drop down and repeat. I wouldn't fancy doing that for 500miles on a round trip.

This might sound wierd but its only what you're doing driving normally (revs, up and down gears etc) and is how a lot of builders will tell you to drive the car.

 

[Rishi]

500miles is all you need... The engine will be well broken in by then...

Give it plenty of rev just not so much boost...

Rev as much as you can while keeping it to 0.3bar... After 200miles take it to 0.5bar... 400miles 0.7bar - 1bar and then by 500miles you can run whatever you want...

Don't sit at constant revs... Go up and down the revs and through the gears... B-Roads are best for this...



Rishi

 

[Fazz]

Thanks Guys.

Did the search but didn't quite get the answers i wanted so post is easier.

@ Campbell - agreed on the motorway miles etc. But it seems to be a myth on running in that 1000 or 2000 miles are needed. I guess most er on the side of caution here but the main purpose being for the rings and it does make sense that you need to give a bit of load to the engine to do this properly in early stages.

Assuming I get car back this week, I will be running in on b roads, mixing up the revs but gradually increasing boost. putting the car under load in 4th/5th and by the 500 miles mark will be ready to go.

An oil and filter change straight away then and its off we go.

I'll let u know how i get on.

Thanks for replies and confirmation lads..

 

[stevepudney]

Thanks Guys.

Did the search but didn't quite get the answers i wanted so post is easier.

@ Campbell - agreed on the motorway miles etc. But it seems to be a myth on running in that 1000 or 2000 miles are needed. I guess most er on the side of caution here but the main purpose being for the rings and it does make sense that you need to give a bit of load to the engine to do this properly in early stages.

Assuming I get car back this week, I will be running in on b roads, mixing up the revs but gradually increasing boost. putting the car under load in 4th/5th and by the 500 miles mark will be ready to go.

An oil and filter change straight away then and its off we go.

I'll let u know how i get on.

Thanks for replies and confirmation lads..

You fool !! :der:

Just think how much time, effort and money have gone into your rebuild, do you really want to risk it all just for a poxy rolling road day.

I would do as Jim says and skip that willie shaking, "I've got more power than you day". You won't do your engine any good at all.

Also What ever you do DO NOT PUT IT UNDER LOAD IN THE LOW GEARS

All engines are happiest when revving free, by loading the engine in low gears you will be putting to much strain on everything.

If you want to go for the 500 mile option I would.

On first start up have correct amount of a crappy grade mineral oil in the engine (castrol GTX or something) start the engine and hold 3000 rpm for a 5 mins at least. Whilst it's doing this check under the car for coolant leaks e.t.c.
Then assuming you have a boost control of some sort turn it off so your running the least amount of boost as possible. Then go for a run, just 25 miles or something driving round the b roads, using rev's up to about 3000 rpm (just drive it as you would if the engine were cold). Avoid using low gears going up any hills, it would be far happier being in 3rd or 2nd and over revving than straining at low rpm.
After your 25 mile run, go home and drop the oil, leave the filter on and replace the oil with more of the same. Then go for another longer run, say 100 miles with say upto .5 bar of boost and take the revs up to about 4000 rpm but still taking care and not straining by using the revs. Then after that run drop the oil AND FILTER. Replace with new Nissan filter and a better grade of oil, say Castrol RS Formula 10w 60. Then go for another run but this time increasing the boost to .7 bar and driving normally without going mad and keeping the revs below 5000rpm. Then once you have reached 500 - 700 miles in total drop the oil and filter and replace the filter with new as before but replace the oil with some top quality stuff like Silkolene Pro S 10w 50, checking all your fluid levels, clutch & brakes, power steering, water, gearbox/transfer box oils e.t.c.

Then you should be ready to go

Steve

 

[campbellju]

Running in cars is not black and white as you've found from your search.

I wouldn't say the 1000/2000 miles is a myth but you've got to take it in context. If you've just replaced every single part on the engine and some parts weren't put in perfectly, its better they are found out slowly through controlled driving over 1000 miles than ragging it at full boost for 200 miles finding an oil leak and killing the engine.

Also my engine started to rev more easily after around 2000 miles as it was as tight as a ducks a**e at first. My wife bought a new Citroen C4 recently that unlike her last car had a strict bedding in routine. After 5000 miles, it now feels like a different engine.

So was my wife's car a 500, 1000, or 5000 mile run in period as it obviously took 5000 miles for the cylinder bores to be honed and bed in?

Food for thought ;-)

 

[Fazz]

You fool !! :der:

Just think how much time, effort and money have gone into your rebuild, do you really want to risk it all just for a poxy rolling road day.

I would do as Jim says and skip that willie shaking, "I've got more power than you day". You won't do your engine any good at all.

Also What ever you do DO NOT PUT IT UNDER LOAD IN THE LOW GEARS

All engines are happiest when revving free, by loading the engine in low gears you will be putting to much strain on everything.

If you want to go for the 500 mile option I would.

Steve

Agreed on the 500 mile option and oil changing and gradual increases.

However u say don't put under load in low gears, if you mean high gears for example put into 4th or 5th when driving up a hill so the car can make it but is under load, then why not??

As this is the best way to wear in an engine I've been told by several sources.

The object is to put a bit of strain on the rings...
And not to rev fully as you say until fully run in..

As for the rolling road comment, its not about I've got more power than you as I know there will be at least 2 if not more cars there with close on 400 bhp - I'm only around the 300-330 mark. And even that would depend on if my map has held out etc.

Its about joining in for the GTI-R's, the fact I've organised it, and to make sure the numbers are respectable.

Also if I have the 500 miles done, then a figure to see what needs doing is required...

I'm not stupid, yes I'm eager but not willing to do a rolling road unless engine has the 500 miles at optimum run in parameters.

Hence why the post was put up in first place.

You start off saying I'm a fool then agree with the 500 mile option? So easy on the abuse ted. You kinda a bit hypocritical?

Can you explain why u said don't put under load in 4th/5th gears and to keep it revving freely please?

 

[Fazz]

@ campbell - fair enough... but my engine is not brand new or had every part replaced.

Pistons and Rings, head gasket and couple other minors but not crank bearings etc etc...

So mainly new pistons and rings, and technically, only the rings would need running in afaik...

Hence the 500 mile option. I may have done a little research, but I've spoken to a good few rebuilders and also why I put this post up.

I'll prob go with the 500 mile option running in at different increments.

Obviously full checking of leaks etc etc..

Thanks.

If you don't put the rings under load near the start, then when you do how can they be expected to cope???
Also food for thought!

 

[campbellju]

[Edited]

My engine builder always used to advise I listen to the engine whilst its being bedded in. Sounds a bit gaybut he meant there is a natural amount of load and rev the car will take, similar to when you start you car cold and it just doesn't sound right when its revving.

Somone did a really good post on this ages ago with diagrams but my own analogy for honing the cylinders is like sawing a piece of wood. To much load and the saw will start to take out chunks and stall, too little load and the saw won't do anything. Too fast and the saw can become unstable and and start cutting in the wrong place. Get the load and speed just right and you can "hear" the saw working.

When honing the bores, you are trying to cut the imperfections rather than file them down and the amount of revs and load will change as the engine beds in.

Steve's programme is spot on and I wouldn't argue with it

 

[campbellju]

If you don't put the rings under load near the start, then when you do how can they be expected to cope???

I've already said I'm not getting drawn into an argument over how hard is hard and how soft is soft ;-)

You say you've only changed the pistons, did you go up a size and re-bore the cylinders or just change them. I don't think I've heard of any pistons done in situ yet so there will have been a lot of parts taken off your car so you've got to be concious of looking out for leaks/rattles and the like.

If you've not machined the cylinders 2 things spring to mind, you're not going to get much if any bits of cylinder wall in your oil and so maybe you don't need the rigourous oil change program but you will always get some engine building debris so oil changes will be needed.

If you're not honing your cylinder walls then you won't necessarily need the high rev/medium load cutting action. If your main concern is just the rings and with the cylinder wall not being a tight fit as on a full rebuild, I can see logically why you would need more pressure on the rings and why low rev high load stuff is better. Your cylinder wall contact will be far looser rather than a duck's a**e, more like a pornstars :lol: :lol:

Again are we talking about putting the engine in fourth on a big hill and flooring it, probably not as there is a sweet spot for everything and whoever suggested this might be considering too. I might be jumping to conclusions here again.

My advice is still do whatever your engine builder advises as he will be the one warranting your work and you'd hope understands better than we what work you've actually done to it.

I still wouldn't put my car on the rolling road even if I were the orgnaiser. You could do what we do in the NW where we all turn up to meets in Non-R's as they are all in the garage :doh: . Ask the builder though, he might have a different opinon and its his opinon that matters.

Jim

 

[Fazz]

Thanks Jim.

Block has been bored to accomodate oversized pistons to answer your question.
So yes debris in oil is a concern and I will be going with 1/2 oil changes anyway.

REbuilder advises to not stress engine until the 500 mile mark, and before that to try put under load for the rings, i.e into 4th and up hill between revs 2000-say 3500/4000. and same in 5th.

Not increasing revs past 4.5k until miles are run up.
And basically the gradual boost as Rishi mentioned in his reply.

So I agree with that, and the research I've done also does.

Others seem like overkill, or perhaps necessary if most internals replaced, but not in my case.

This is the first GTI-R meet over here in quite some time, hence I'm eager to be present and with R.. Obviously Rolling road is more so.
Don't think we'll ever have the non R meets as fairly wide speread across teh country over here.. only 2/3 in any one location ..

Anyway, thanks all for the advice, I will go with engine builder and more knowledge gained from here.

 

[campbellju]

Block has been bored to accomodate oversized pistons to answer your question.

8) 8) I'm glad you said that. It sounds like your engine builder has it all covered.

Another thing I wish I'd done was the magnetic oil sump plug a i know mine was deliberately a tight fit re-build but the amount of metal that came out of the engine, these sound like a good investment.

 

[Fazz]

8) 8) I'm glad you said that. It sounds like your engine builder has it all covered.

Another thing I wish I'd done was the magnetic oil sump plug a i know mine was deliberately a tight fit re-build but the amount of metal that came out of the engine, these sound like a good investment.

I have a magnetic Oil filter waiting to go in and take most of the debris in after rebuild..

Hadn't heard of a sump plug version but sounds similar and a good job!

Cheers.