What's the break in period before you can start beating on the car?
I mean at how many miles do these type motors [ls1] lossen up,
or do they stay this way. 2002 w/ 6 speed :chevy :cheers:

 

500 miles is what the book says (I first went WOT at 535 miles) but they improve steadily with time. I first went to the drag strip at 6500 miles and the second time was today at 9500 miles. I gained 0.1 seconds in the quarter mile at a different and notoriously low grip track.

My fuel economy has improved noticeably during that period too. Mind you my last car's fuel economy got better and better as I clocked up 38000 miles so if the LS1 works similarly it should be good for smiles :yesnod: to come !

 

500 miles is what the book says IMO it is just as important to vary the routine. Go lots of different engine speeds with not much high RPM.
The brakes are just as importamt. 6 or so moderately hard stops from 45 that are spaced far enough apart so you don't get the brakes real hot will help seat the pads.

 

The book states 500 miles. I went into the motor at 1,000 with a boroscope and I can tell you the rings won't seat that fast. The hone marks were fresh, and with synthetic oil they will take some time to wear in.

 

The engines are run at the factory .... Vary the RPM up to 500 miles with no loads. After that go for it a little more each day. :smash: :cheers: The engine has a limiter so you can't over rev it. I wouldn't bounce it off the limiter every shift but the LS1 loves to rev. The worst thing you can do is bog the vette around after break-in :nono:

 

I bought a LS6 crtate motor, it wasn't even started. Pistons were squeeky clean.

 

Thanks all :flag :chevy

 

Rockystoy,

I break my engines in with WOT bursts, but the secret is NOT to take it above 4000 RPM, then let the engine coast down to about 2000 RPM. For the 6 speed Vette, I used 4 gear. Then hold a steady speed for a couple of minutes and repeat.

That was the procedure that GM reccommended once upon a time. It still works for me.

The cylinder pressure is greatest when the throttle butterflies are open...or at WOT. The fuel/air charge is greatest and the mixture should be on the rich side then. The combustion gases find a pathway, by design, behind the compression rings and press them forcefully against the cylinder walls. That helps the rings wear to the cylinder bore.

After you hit the 4000 RPM mark, take your foot completely off the throttle...to insure that the butterflies are all the way closed; that's when the vacuum in the cylinders is greatest and the pressure differential between the cylinders on coast down and the crankcase will help draw oil up into the ring/cylinder contact area for lubrication and cooling.

I have 25K on my 2001 coupe and it is still wearing in....at least the oil milage so far is better with each change...so I'm guessing that is the case.

That's my method and the reasons for it. Others have their own method.

For peace of mind, do what the General says for the first 500 miles and then IMO, they need some driving....try to keep the rings loaded as much of the time as you can.

Good luck.
Mark

 

 

Should the breakin remain the same for auto as compared to the 6 speed?