tk's944

I just finished up my rebuild and now it is time to drive it. There is a lot of different opinions on the subject, the only one that I have listen to so far is keep changing your gears to help keep the oil moving. So what are your suggestions.

bjzorn

As per Porsche's recommondations. Don't rev higher than 4200RPM for the first 2500 miles. I would also recommend changing the oil after the first 1000 miles and then again after the full 2500 miles.

tk's944

Uh.. to late for that

KuHL 951

This guy seems to have a strong opinion. He has his following in the V8/Sport Bike crowd but I think it might apply better to CI bores than Alusil. Some of what he says makes very good sense though.

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

Zero10

I've heard 1000 ways to break in your engine on here...
When I rebuilt mine I used straight 30W oil for 500 miles, then changed it for a conventional 20W50 for 500 miles then changed again and ran for 1000 miles and filled with synthetic then drove the pants off it. When breaking it in, be scared of the rev limiter, treat it with respect. Once you have hit 2000-2500 miles, treat it as a target and fully enjoy your new engine.

Just umm.... don't put your rings on upside down, okay?

adrian_jaye

TK,

run in from a man who knows his Zhite

"1 As soon as the engine fires up, bring the RPM to between 2000 and 2500
RPM and hold it there for the next couple of steps.

2 Monitor the engine on a 4 gas analyser and an ignition scope, make
alterations to the fuelling and ignition the whole time its running.

3. run the engine like this for 15 mins

4. Drain the oil, replace with fresh mineral oil

5. take the car out for a 20 to 30 mile journey of varied duty cycle. in
other words a mix of duel carriageway and urban, with minimum idling, and
regular use of acceleration, never exceeding 75% of the maximum engine RPM,
but using full throttle when possible.

6. drain oil and replace with more mineral oil

7. Hand car over to customer for 1500 miles, with the instructions of
never exceeding 75% of the maximum engine RPM

8. change oil for fully synthetic and tell the customer to drive it as
they please.

Lemming

I've always flogged the $&!~ of every dirt bike I rebuilt with no problems. Plan on doing the same with my car when I rebuild them. Of course YMMV

RMills944

Just make sure to heat the headers up nice and good... This may take hours at redline, but just make sure to melt them to the block to ensure a good seal!

xsboost90

what did you do during the rebuild? if you didnt pull the pistons or put a new cam in it, just new bearings,break it in under varying rpms for 500 miles and then change the oil/filter. There is usually alot more wear/debris when breaking in bearings than any other time.

Mongo

According to Porsche's break-in procedures, take it easy for the first 500 miles. Change the oil at 500, then again at 2500.

For the 944, DO NOT use Synthetic oil to break in the engine! use conventional grade oil, like 20W-50. Anything after 2500 miles can be synthetic.

tdub

There are so many theories.

Just remember to always get to operating temp before going hard and keep the oil clean. Everything else is strictly opinion.

tw

Mongo

I think the next most important one to operating temperature is never abuse a new engine.

V2Rocket

this should do it.
http://youtube.com/watch?v=Fy3NprPD6x8