I dont think that has anything to do with engine break in, Id be more inclined to thinking it had to do with the brake pads.
Notice, No "extended" WOT pulls before 100 miles. So, no going 120mph in the first 100 miles ^_^


Also,

I honestly don't know why they tell you to take it easy for a thousand miles. It makes no sense to me.

When your cylinders are freshly honed, you can basically think of them as V's going down the walls. They have peaks and valleys. The goal of motor break-in is to wear down the peaks without filling the valleys in. You want to wear the valleys down to the point where the ring supports itself without filling the valleys in with metal shavings from the peaks. Too much boost will press too hard on the rings and glaze the walls. Too little throttle won't push hard enough and you'll glaze the walls. Not enough decel and the metal shavings will collect in the crosshatching and create a big issue. High throttle loads will press gases down into the ringland and press the ring out against the cylinder, which wears the peaks down. The decel part will draw oil up onto the cylinder, washing out the valleys from metal shavings and keeping the cylinders cool. Good deliberate break-in is nothing but on/off throttle pulls, no boost, starting at ~3k RPM and going up until redline. Once you are done, you should notice the motor pulling more vacuum.

This is how you break in 2-stroke kart motors, BTW - shortshift 2 sessions (first session ~9k, 2nd session 10.5k) and then go for it (12k+).

Good break-in practice is a ~90 second warmup, followed by an oil change, followed by 30 miles of severe city driving. That's all it takes. Once you've done ~50 miles or so, take it to the dyno and beat on it.

:bowrofl:
are you drunk?

Well shit.. you've all convinced me for my round 2 of break in. I was planning to wait 1000 miles before putting the turbo on it, but fuck it, I'll just seat the rings and add go fast parts as soon as I've collected the last few bits and pieces.

I want to break the motor in with factory management to eliminate possible issues with tuning/doing too much all at once. I will then add my megasquirt get some base tuning going and then i can add injectors, vtps, etc.

I dont have the luxury of breaking in my new engine with stock management, so my question is, should you be breaking the engine in with a 14.7ish air/fuel trim or a slightly more rich or more lean to avoid any wash out before the rings seat?

Just curious, never done this before.

If we're talking about the same "wash out" where the fuel coats the cylinder walls enough to wash down the oil, there is no way in hell you'd do that unless its something ridiculous like below 10:1

Run it like a Kenyan but with no boost. WOT at 11:1-14:1 should be just fine.

So I am running the car on factory managment NA stock setup but the car is running rich. I get about 20mpg. My guess is low compression is causing this, any ideas? car runs smooth warm, cold start it sounds like its missing, for about 10-15 sec then sounds fine. I think car is getting way too much fuel...but any help is appreciated. I'm thinking of throwing the megasquirt/wideband on it and checking fuel ratios with laptop.

????? 450cc injectors? no bandaids?

No Factory 1.6 everything Naturally Aspirated.