anyone get a set of these on the dyno yet to compare them to a set of DD Super Mentals?

 

I will be looking for a more powerfull inj than the dd3s I have now . Sorta waiting to see some more results from edm type. Smoke is not a problem to me but Im worried about cyl. wash down cold. Don are your 120-140hp inj putting any noticeable amount of fuel in the oil when used as daily drivers? Thanks Tim

 

Tim,<br><br>I will answer in two parts. First, the EDM injectors we have do not cause cylinder wash down. Even cold. Actually quite the contrary. Ours have a high combustion effeciency compared to the typical high HP injectors of the same power level.<br><br>Secondly, soot formation in diesel jets can be attributed to a large number of factors. These factors include but are not limited to the following:<br>1. Insuffecient air or oxygen to oxidize all the soot or soot precursors.<br>2. Insuffecient mixing of the air and fuel before the soot particles become too large for oxidation in the time available in-cylinder.<br>3. Poor ultilization of the the air in-cylinder in the outer area of the combustion chamber due to slow penetration of the fuel jets.<br>4. The fuel jet being too close to walls to allow air entrainment.<br>5. Liquid impingement on combustion chamber walls with insufficient air motion to mix the fuel off the hot cylinder walls<br>6. In-cylinder temperature hot enough to form soot, but low enough that the soot formation is slow.<br><br>We included these known conditions and few others (censored to keep the competition guessing) when we started this project back over a year and half ago.<br>Our injectors produce lower particulate matter, and grams of soot emitted per kg of fuel injected. We took into consideration the swirl ratio of the Cummins B series for the 12 and 24 valve engines as well. Swirl ratio is the speed of the air in-cylinder when compared to the crank rotational speed. The 24 valve has an air rotational speed of over 3000 cylinder revolutions per minute under some conditions and engine speeds. This number is constantly changing depending on if Bubba has ported the head wrong or if the boost numbers are increased with certain parameters in engine speed that can help or hurt combustion efficiency. <br>I bring up soot conditons because the same parameters needed to make the fuel oxidize and unzip the hydrocarbons efficiently go hand in hand with the conditions you need to not wash down cylinder walls. I have seen video and read reports of some of the EDM injectors that spit and splatter fuel so bad it burns yours eyes from the heavy unburned aromatics in diesel fuel. This is a prodcut of inefficient design, IMO. <br><br>Sorry so long winded in the reply. I just wanted to spell out that anyone can go and punch holes in an injector tip. &quot;Safely and effectively&quot; is another question all on its own.<br><br>Don~<br><br>

 

Some interesting pics.

 

got a question, is there a way to tell if an injector is leaking when it is in the engine?

 

leaking how?, The seat or sealing area you mean?<br><br>Don~<br>

 

leaking however they can leak. I'm just wondering. ???

 

They can leak between layers if they are old are have been assembled with dirt or trash in them. Or the seat or needle sealing area has been worn out from excessive honing media passing over it or just plain wear from use.<br><br>Generally a layer leak will show up in the oil on a 24 valve or visually on a 12 valve. Needle sealing troubles are harder to detect. I have listened to many different types of injectors and delivery valves with a scope so I can now tell what is right and what is wrong nearly every time with the truck running.<br><br>You can carefully loosen an injector line one by one and listen for an audible change in the way it runs or look for tiny air bubbles in the 12 valve trucks.<br><br>Don~<br><br>

 

thanks for answering my question Don!

But now I got another one, besides being pure unburt fuel, and a possible sign of wash down, what does it mean when white smoke is comming out of the tail pipe at idle? And is this possible on a 24v?

 

Andrew,<br><br>My truck started blowing white smoke when the turbo started to go. I also got a bunch of soot build-up in the tail pipe. It appears to be the oil seal in the turbo but until Piers tears into it I wont know.<br><br>Nathan

 

Generally the pure white smoke is unburned fuel. You can really tell by smelling the strong Acyclics or Aldehydes in the fuel that are not being completely combusted. You will only need to smell that one time and you will remember it forever.<br><br>In many cases with this problem it is either cold as he!! outside and the in-cylinder temps are not high enough to burn the fuel or the injector is having seat or sealing problem.<br>When I dont plug in my truck on a cold morning it will blow white smoke for 15 minutes from the cold temps. Once warmed up it is ok.<br><br>If you have a truck with a sticking injector it will blow white and generally run poorly even when warm. A bad stick will fill the cylinder with fuel and hydrolock the engine. <br><br>Don~<br><br>

 

Push Rods 03' has a nasty NASTY smell even warmed up.<br>It dang near killed us out back one night. <br><br>Very raw fuel

 

Yeah it stinks to he!!. We did find the oil smell getting on our nerves too, from the crankcase breather on the vavle cover thingy YUK!!<br><br>Don~<br><br>

 

[quote author=Don M link=board=7;threadid=10249;start=30#106985 date=1045766162]<br>Yeah it stinks to he!!. We did find the oil smell getting on our nerves too, from the crankcase breather on the vavle cover thingy YUK!!<br><br>Don~<br><br><br>[/quote]<br><br>I got a nasty whiff of that in the cab one time too.<br>I thought maybe a dead sheep was under the seat.<br>

 

So at a warm idle, with white smoke, and no other problems, white smoke would just mean the injector is flowing lots of fuel right?<br><br>thanks for answering my questions.