> Ok, thanks. Yes I have seen this before, and I'll give it a good read over
> before I decide the first 1/2 hr of this motor's running life. (revving
> 2-4000 rpm?)
>
> The engine builder and cam grinder both only recomended keeping it above
> 2000 rpm for the first 20-30 min. Nothing said about driving the darn
> thing so I assumed that first half hour would be revving in the driveway!
> (Don't think the neighbors are going to like that too much.)
>
> After the initial 20-30min break in I was thinking city/country drives, no
> long periods idling or sustained rpm, slowly working up in steps to
> redline over a couple weeks/few hundred miles?
>
> Does this sound reasonable? I'll talk to the engine builder also to get
> his thoughts also. Then decide the best route. The more ideas the better,
> even controversial ones!
>
> Thanks
> Daryl
>
> ----- Original Message -----
> From: <RacerY@comcast.net>
> To: "Datsun Roadster List" <datsun-roadsters@autox.team.net>
> Sent: Sunday, October 23, 2005 11:46 AM
> Subject: Motor break- in, was SU setup for 1800cc
>
>
>> So I did a little more digging,
>> and it's all about ring seating.
>> here's the link:
>>
>> http://www.mototuneusa.com/break_in_secrets.htm
>>
>> The gist is that you want to keep high cylinder pressures, NOT
>> necessarily that you have to flog the motor mercilessly.
>> Airplane engines seem to want the same treatment:
>>
>>
>http://www.lycoming.textron.com/main.jsp?bodyPage=/support/publications/keyReprints/operation/engineBreakIn.html
>> http://www.cessna.org/benefits/articles/breakin.html
>>
>> and I've done basically the same thing on the last 2 motors I've rebuilt,
>> with some success. Warmed it up, then taken it up 99 late in the
>> evening, accelerating to 60 in 3rd with heavy throttle, (maybe 4500 rpm)
>> then letting it drop to 40 by taking my foot OFF the gas, and repeating
>> ad nauseum. Or at least 20 times.
>>
>> Having said that, if a professional's rebuilt the engine, BY ALL MEANS
>> follow her or his instructions.
>>
>> As for cam break- in, the cams I have used have explicit instructions to
>> avoid idling, saying "Keep RPMs above 2000 for the first half- hour."
>> This DOESN'T mean that you HAVE to run 2000, just that low rpms will be
>> harmful. So if you run several load cycles, just don't let the thing
>> idle.
>>
>> Again, following the instructions for the specific cam is, as they say,
>> 'priceless'
>>
>> Just my '02,
>> Toby
>>
>>
>>> The 'theory' of which was written about is a disputed one.
>>>
>>> The grinder of the cam I used, Malvern Racing, which built a lot of
>>> motors
>>> for the Datsun community, disputed the 'run it hard approach'.
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