Prechamber Mod "Flame" Front

OM616

10mm MW

572

01-25-2011, 11:01 AM #32

(01-25-2011, 12:16 AM)ForcedInduction
(01-24-2011, 07:03 PM)ronnie The larger the hole the better it will flow at higher speeds.
ronnie, flow is not a good thing in a prechamber, thats why it was designed with orifice holes.

The concept behind a prechamber is to atomize the fuel; it does this with by burning a very small amount of fuel inside the prechamber, which blows out the vaporized fuel for it to burn in the cylinder. Increasing the volume of air inside the prechamber is pure wasted energy, the combustion pressure is pushing on the prechamber walls instead of the piston.

That is better. So to be sure I have it right, your understanding of how the prechamber works is that a very small percentage of air is pushed into the prechamber, (would it be fair to say you are thinking less than 15%?), and that the injected fuel passes through the prechamber to the cylinder, propelled by a little fuel burning in the prechamber, and that the majority of the fuel 90+% is ignited and burnt in the cylinder.

It is important that I understand you correctly, in order to post a counter argument.

On a side note:

(01-25-2011, 12:16 AM)ForcedInduction People like Jeemu have validity in modifying them because the large volume of fuel injected becomes restricted from flowing out of the prechamber. Jeemu is making 220hp per liter, OM616 is still making only 72hp total.

Did you intend to imply that when Jeemu starts his engine that it instantly, and only makes 220hp pre liter?, because that would it a hand full to say the least. What about when he doesn’t have his foot to the floor? You know, it has to idle and be able to putt around, making only 72hp total or less, like me, or are you saying that his engine runs like crap, smoke, high EGTs, no power, until he floors it?

Regarding some of my measurements, In my last post, I posted that I measured cylinder compressed gas temperatures in the 900+ degree F range, pre-injection, I have not posted, but during high speed piston velocity tests, I measured cylinder compressed gas pressures in upwards of 1000PSI and prechambre pressures (at the same time) of 280 to 315PSI range. The closest pressure differential was below the 2000 RPM range.

I also posted that I saw a drop in high speed EGTs and was able to increase fueling for the turbo motor beyond where it was smoking with the stock holes. The turbo built boost sooner, (at a lower RPM), as well.

(01-24-2011, 09:20 AM)jeemu
(01-24-2011, 09:05 AM)ForcedInduction jeemu, are those stock?
No.

Jeemu,

Can you confirm if there are holes all the way around the tip. If so, I figure there would be 8 holes.

The manuals I have do not say what the hole diameter is or how many there are.

Many thanks.

This post was last modified: 01-25-2011, 04:04 PM by OM616.