hey guys... so just a quick one here. finally have the motor all together, waiting for the hedders to get here, so I can drop it into the car. Just wondering what you all think for break in on these ls engines, seeing as this was the first lsx my machinist had done, he wasn't really sure, suggested the typical "easy break-in" with oil changes at 30, 200, 500, 1000, 2000, 3000 miles. So figured I'd better ask around. the motor has all new bearings, seals, rings, and valve train (including head castings). Also I was wondering how to set the carb up for these intitial runs. I know the carb was running ultra rich on the stock long block before hand, mostly due to the booster valve I think (rear blocked off, front 8.5, thats how it was when I got the carb) its a holley dp 750. Any thoughts comments would be much appreciated, thanks

 

If the engine does'nt appear to be "tight " or exhibit any obvious problems......drive it like you stole it. Ron

 

I started my new build up for the first time yesterday. Not much break in is really needed with the newer engines with roller cams. Start with a safe tune, not too much timing.

This is what I do after I start an engine for the first time, check for leaks, vary rpm to seat the rings in, let it get up to operating temp, adjust carb as needed. Then change the oil. After that just drive it. I would suggest changing the oil again after a few hundred miles. For piece of mind I go easy on it for a little while but you really don't have to.

 

If it is going to break, it is going to break, if you MUST break it in, drive it for 500 miles normal with minimal abuse, then change the oil and give her hell.

 

Well i picked up some valveolean desiel oil( no additives) and a cheap filter, figured 30 miles to my apt and back. then change it all, and drive it normal for maybe 400 miles??? plan on flushing the coolant system before start up, and at the first oil change. My main concern is just seating the rings and the brand new double springs up top. As far as timing does anyone know the curves on the pills that come with the 6010 box, or which one to use for that matter. I don't yet have a laptop with the program in it yet, also can anyone recomend a booster valve size to use, I have the 8.5, 6.5 and 3.5, I know its better to run rich than lean, but cant hurt to ask right???, thanks for the input so far guys, this engine would be just a wet dream if not for all of you!

 

Run it hard. Not 100% hard but 80-90%. Pull the engine up to a relatively high rpm and let the engine slow the car down several times. This will seat the rings.

 

It is difficult to make a recommendation on which power valve to use without knowing your exact combo. I would start with the 6.5. The old school rule of thumb was to measure the vacuum at idle, divide by 2 and add a half. So if you've got 13 inches of vacuum, then you'd start out with a 7 power valve. It really is a matter of how you set up the car to run. The power valve circuit in the carb is designed to richen the primary circuit when the throttle blades go to wide open throttle. A lot of guys that use a wide band to tune their cars throw that power valve rule out the window to achieve a better fuel air mix. This leads to better fuel economy. I guess you really just need to experiment to figure out what works best for you.

 

Look at the timing curves with the paperwork that comes with the ignition box, usually number 3,5 and 6 are mentioned to be used as a base line.