Mileage king, I broke it in my way ( Idiots Motor Break in)

[Lewis Shadoff]

At 01:58 PM 3/1/02, you wrote:
> >The Chevy engineers said "OH NO, you want to break it in HARD if you want
>it to be fast."

>Ok, I'm surprised no one else has commented on this.  Every break-in
>procedure for new cars I've always read has always said the same thing:
>"keep the rpms low, vary your speed, no full-throttle starts", just
>essentially drive the car like a granny for the first xxx number of miles.
>This is the first time I've ever heard a hard break-in recommended.

In large part it depends on the kind of rings.  Chrome or cast iron rings
are used with a cylinder bore finished with with a #400 stone leaving a
cross-hatch pattern in the bore.  Break-in slowly wears this pattern
smooth, and the rings end up sealing perfectly.  During the break-in, there
will be significant blow-by at high cylinder pressures, and this will
interrupt the break-in process if done too much.

If the engine has chrome-moly rings, the cylinder walls are finished smooth
(#800 stone IIRC), and the soft ring surface seals very quickly.  In this
case, immediate full throttle acceleration seats the rings in minutes.

Lew

Lewis Shadoff
Lake Jackson, TX
'97 200SX SE-R, Level 10 Auto, HotShot turbo
http://www.brazosport.cc.tx.us/~lshadoff/turbo/