Hey Guys, What do you think about this:?
http://www.mototuneusa.com/break_in_secrets.htm

Well, I didn't know they were "secrets",, but I can tell you that his dyno recommendations are almost exactly what we have been doing for years & it works for me.
I warm the engine while varying speed with no load for about 20 minutes, put it under a light load from about 2000-3500 for another 5-10 minutes, (the dyno will cycle it between these set points for as long as you want) shut it off & check the filter & readjust the valves if necessary.
Start it back up, do a few lighter pulls to 4000, then 5000, 6000 etc depending on what it is, then hammer it & see what happens :D
Most times you smile smile.gif ,,, sometimes not,,,, :(

So you think its not a good idea breaking in the cam etc in an engine stand because there will be no load on the engine?

The cam doesn't know if the motor has a load on it or not. Breaking in against a load is for the rings.

Woot! Now I feel better about my break in. After 200 miles it was at the track! And I didn't baby it before hand (no abuse either though) :D

I pretty much followed his ideas. 20 minute cam break in then down the strip for some WOT, 7000 rpm runs. No babying it for me. :D

I babied my engine because everyone said not to treat it too hard if it wasn't built for racing. So I kept it well under 4000rpm for the first 1000miles or so after the 30 minute cam break in. It seem to be doing ok to me. Then again it wasn't too long after I finished babying it that I was doing burn outs, launches and shifting at 5000rpm on the racetrack. Maybe I made up for it? LOL.

So let's say I wanted to break it in like this, with a solid cam. I have no engine dyno or stand, the motor will be in the car.
If I break in the cam with just the 'outer springs' on the valves, should I do the cam break-in and then fully assemble the springs before taking it out for the pulls 'under load'? Or should I take it out immediately while the engine is good and hot from the cam break in?

Or stop, let it cool, do the springs, warm it up again slowly, then 'load' it?

DO NOT put the engine under "load" With just the outersprings. You'll float the valves like a mad man!


After I broke in the cam, I put the inners back in, as was instructed by Harold's buddy at Lunati!

Ah! love those rollers, no break in. graemlins/hurray.gif