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What is the best process for running in a new short engine? (By short engine I mean the engine minus cylinder head and all ancilliaries, which I recently purchased new from Porsche Parts. Note it could not have been run at all, even on the bench, prior to delivery).



What is the best oil to use, the driving style and duration. Some advocate running the engine initially on a conventional non-synthetic oil to facilitate the rapid bedding-in of piston rings into the bores, thus improving long term piston ring seal. The oil is changed over to synthetic oil after the initial 100km or so of run-in.



And how would you drive during the run in period? This web site has some very interesting / controversial views, claiming you will get better ring seal = more power in the long term if you run the engine in hard .... Mototune - run the engine hard during run in

Is the head/cams going to be new as well? The process is different for just the bottom end or the top and bottom.

P.S. That is an interesting atricle on break-in of an engine. The idea makes sense, but im not totally convinced.

use full synthetic



here is what i do - it has been VERY successful:



first thing to do is find a very long steep hill - after warming it up fully, then take the car up that hill in the highest gear you can - really lug it - this will expand the rings and seat them really well - this should be a good 10 minutes - if you have to do the hill a few times to do it, that's fine



further, don't exceed 4k for the first 500 miles - also, do not full throttle for the same period



then, change the oil at 500 miles



then, drive normally, but do not push it for the next 500 miles - brief revs to near redline are fine



after that 500, feel free to do whatever you like



change the oil again at 2k



after that, oil change as normal



slightly higher than normal running temps for the first 1000 miles is normal

I'm surprized the engine didn't come with some instruction... <img src="/forum/images/smilies/968/blink.gif" class="smilie" alt="" />



I know there's a lot of knowledgeable folks online, but I'd consult Porsche on something as critical as break-in.



FWIW, I've also built a few engines and typically it's best to take it easy for the first 1K miles [no bursts to redline] and vary the rpm on the highway, [don't maintain a constant rpm for too long].

And, as you probably know, check the balance belt tension after 1500 - 2K miles.

Good Luck...

[quote name='968workaholic' post='40949' date='Sep 9 2007, 10:31 AM']Is the head/cams going to be new as well?[/quote]



no the head / cams are not new, but in top condition. They have only done 40,000km (~24,000miles)