Sounds like an ameteur question, but once the engine (409) is fineally running, how much running time is necessary before hitting the dyno and tuning...usually there isnt any, but I need to break this in correctly...prefer one engine per season...any input?

 

I would go over 500 miles.......my motor was burning a little oil up until this point.....

It was abused right after getting started w/boost though..........

 

I plan on running my new motor for 500 miles first at least. Then im going to change the oil and go dyno. Im not even going to hook my blower back up till i have at least 500 miles. I was thinking maybe more closer to 1000 miles to let the rings fully seat....... Then its all booost.
Kyle

 

Run it long enough to get all the imputities off the moving parts and into the oil and oil filter, change the oil, then give it hell!

 

And...with 72lb injectors chances are 500 miles aint gonna be no easy task...I guess I can at least putt around on the stock injectors and tuning...then after a few hundered miles get the GEN 7 and tuning andf 72lbers in...any problems with that idea?

 

Haha. They tuned the idle some and changed the oil and then motor hit hit the dyno.

 

Something tells me it could end up that way.

 

Here is my .02.

What makes the rings seat well is the filing effect the crosshatch on the cylinder walls has on them. When the ring is in its groove, what kind of pressure can it exert on the cylinder walls? Not much, maybe 10 lbs. The outward spring pressure of the ring itself is just not that great. What makes the ring press against the cylinder walls with enough force to hold the cylinder presure required to amke 500+ HP is cylinder pressure itself. Air get's by the top ring, and sneaks around inbetween the piston and the ring, forcing the ring out. The greater the cylinder pressure, the greater the outward force placed on the rings.

Within a few hours of startup, the filing effect of the corsshatch pattern on the cylinder walls is greatly diminished due to normal wear. If you have not supplied enough outward force on the rings at that point to successfully "file" them to the exact shape of the cylinder, you will have a difficult time getting the rings to seat properly.

I'm not syaing go out and give her hell instantly, but... IMO the best way to break it in is on the dyno. Make 3 pulls at 60% throttle up to 60% of redline. Let it cool, and the do 3 pulls at 80% throttle up to 80% of redline, let it cool. Then make three pulls at 100% throttle to 90-95 % of redline and let it cool. Then give it hell. It's VERY importatnt that the dyno guy does not release the tension on the dyno after each pull as well. The engine must be allowed to wind down with a load on it.

Th reason owner's manuals and things say to be easy on an engine at first, is that people will interpret the above method incorrectly, and give a brand new engine WOT blasts immediately.

My .02