running in after rebuild
Turbo Mini Forums

hi,

i'm looking to do a complete rebuild to the turbo engine going into my mini,

it will be fitted with new AE pistons and rings, new uprated cam, and a new stage 2 head. the turbo will be a new IHI equivilent of a T25 set to 10psi to start with.

what is the running in process for a rebuild like this?
how many miles do i have to go at what rpm etc.

i will be fitting the engine straight after MITP and hope to be able to go on the track at the the action day at castle combe without having to hold back.

any advice would be great, so i can plan how many miles i need to put in before castle combe.

MAtt.

please get some hot and cold starts on 8..ish mile journeys

and a minimum 500 miles is some where right, but............
many peeps! differ on this, i

ts only my opinion more miles would be better but only run small amounds of boost

Synthetic oil is not needed with this running in period

One of the most important things is to make sure the running in is done with varying revs, as sitting at the same engine speeds whilst running in will tend to polish the bores and inhibit proper ring bedding in. Therefore although it is miles you need, sitting on the m-way is not the way to achieve it, really b road etc driving is best, or even round the lanes, as stopping and starting, speeding up slowing down (all done gently) is the best way to run in. A bit of motorway or dual track work as well intermixed with this won't hurt, but variety is the key. 1,000 miles is really best if you can achieve it.

what max revs shall i take it to?

i run the car for 50 miles, change the oil
250miles change it again
then at 500 on mineral oil
and 1000 if i can be bothered to go that far

i keep to 3000rpm for the first 150
then 4000 up to 500, gradually increaing it after

then get it set up on the rollers

Running in an engine is all about bedding in the rings, bearings/cams etc. are pretty much run in straight away. In fact, you start running valve seats out from the word go.

I never get chance to run in my race engine and I have never had a problem (resulting from no running in that is). Having said that, I think it is generally acceopted that to get the most life out of your rings some running in is advised. all good advice above, 500 miles should do it IMO.

Wil

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

What's The Best Way To Break-In A New Engine ??
The Short Answer: Run it Hard !

That is, of course, assuming that your engine has a fine hone. You would need to check this with your engine builder.

That's an interesting read, and as it is the way I run my engines in I can't really disagree. However, there are some obvious holes in his arguments. For instance, even at 3000rpm, your pistons are travelling up and down the bores at 50 time as second, so any benefits of the hone will surely still happen as this is hardly a gently rub up-and-down the bores.

Also, he says that if the rings aren't forced against the bores soon enough, the only solution is to get new rings and re-hone. this assumes that once rings wear in they no longer wear?

It's silly me arguing, I pretty much agree with him.

Finally, if you have bought a new car in the last 10 years you'll know that you no longer are advised to run them in by the manufacturers.

Wil

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

He is writing mostly about bikes and snowmobiles though, there you have running in time. that may be the cause of his high rpm talk too... I also think that read is a good one, and about the ring wear, I guess he means that it will take AGES to wear them in if there are no roughness left. I also run in my engines this way BTW

As said above you are only running in the rings. This takes a diffrenet amount time depending on bore finish and on piston ring material.

You MUST run mineral oil and prefereably fairly low quality for this period - you WANT wear to occur!

Important factors to consider are the which driver actions will aid run-in. The rings are pushed onto the bore by acceleration and pulled away from the bores on over run. So the engine must experience both running conditions.

So for example accelerate (not too hard and not on boost) up to 3,500 and then back off and let the engine slow down to 2,000 rpm.

500 miles should be enough but its fairly easy to tell. When you stop smoking and the oil consumption drops your rings are run in.

It took 5000 miles on the 1st mini engine I built years ago I believe the problem was too much constant speed and too little load.

Alex

AlexF

I.E. the methods I described above.....LOL

I can say from personal (bitter) experience in the past running in no less than 8 rally car engines in a period of about 3 months that this is the quickest way of getting the rings to bed and the smoke and oil consumption to stop........

Driving rally cars about through the night on limited rpm to get them run in is not the most enjoyable pastime I can tell you!

I did say "as above" hehehe

just added my words because I'm stuck in a class room waiting for people to finish a test :)

Alex

AlexF

Ha! I am stuck at home wondering whether to open a beer or the garage.......

Tom, I disappointed in you....


the answer is SO simple....


Do both!!



Alex

AlexF

my running in has consisted of a low boost (1bar) effort on the rollers and it seems to be doing the trick...

we'll see in time but i'm sure it will be ok.

Ha, LOL

Started the engine on the monday, MOT Friday, Drive to Avon from Northwich roughly 200miles on it and Ragged the arse off it on the sunday, 6500rpm. Still going well.

If it goes bang then fine, adds to the fun.

When you start the engine for the first time do you have to bring the revs up to a certain amount and keep them there to run the cam in? A mate of mine said he run his camshaft in for 20mins at a set rev, what do you guys do?

start it and as quickly as you can bring the revs up to 2k.

Then vary the revs 2-3k slowly for 20 mins.

Alex

AlexF

nearly all oils have an aditive pack design to proect under conditions like cams/valve train.

Alex

AlexF

Pete do i assume you use duckhams Q mineral to start with and then move onto synthetic/semi synthetic?

Minispares sell duckhams q 20/50 i believe if this is any help.

so if you fit a new cam and rings, I assume you run the cam in first?

Or can you run the cam in whilst driving?

https://www.facebook.com/pages/Fusion-Fabri..._homepage_panel

www.fusionfabs.co.uk



1/4mile in 13.2sec @ 111 terminal on 15psi

Yes, you have to do the cam first, run it above 2500rpm for 20 mins as soon as the engine will start up.

Peter, i would be interested to know your take on valvoline race oils, they do a 20/50 and have previously been told that its good stuff. Is this true?

I've seen the future and tbh its Pie