Spray pattern discussion

dangerous06

dangerous06

diesel tech
Can anyone point me to a thread that discussed pro's and con's on best spray pattern angle versus 5 hole or 8 hole?! If the guru's would please post up the test results and conclusions I WOULD really appreciate it!
Reason for thread is deciding on which bowl type and injector style to run in a 6.4 build Both early 04 and later 04.5 07 types are available for the 6.7.
 
Interested. I'm not sure which piston i should choose. I've heard stick with the stock piston, and go with with the wide flat bottom.

I'm going to use a 146* 5 hole nozzle from F1, I believe the stock 6.7 cone angle is 146* as well so a stock piston should work well, right? But when looking at the marks on the stock piston makes me hesitant to crank it up.


image_zpsj4g6fprt.jpg
 
It appears the 6.7 marine pistons are non reentrant style like the 04.5-07 pistons. For this reason I don't see why one I would want to use it in a high HP application. I'm defiantly no piston guru so if I'm wrong please enlighten b me
 
So the 6.7 automotive is a 8 hole the 5.9 is a 5 hole. the 6.7 industrial is close to the 5.9 bowl so would a 5 hole 05 07 injector be the best combo or?
Blacks cuts there own bowls and uses a 143 spray pattern. But their parts are not available so my question is which bowl with what injector works best?
Which tip 5 or 8 I think there's also a 7! I hope someone that has run various set ups comments! So many choices I want to get it right the first time!
 
Not to mention that there are countless other nozzles that fit on cummins bodies including wider spray angle Duramax nozzles and even the nozzles on the European version of the KIA Sorento according to Weston
 
We have had nothing but awesome results with the 6.7L Industrial Cummins piston with a late 5.9L injector spray pattern. they're much more forgiving on tuning the the stock 6.7 piston and 143* pattern and on the dyno have always been able to get 40-50HP more out of the industrial piston/late 5.9 spray pattern then the stock 6.7L piston and 143* spray pattern. I base all my opinions on real world results and that has been my experience. My deckplate engine has a 6.7L industrial piston and Late 5.9L injectors.

Lavon
 
I think it makes more power because there's more area for the mixture to swirl and combust effectively and quicker. I think with the 325hp bowl there's to much of a good thing going on which could explain the multiple meltdowns.


Fwiw most mechanical injected trucks use a wide shallow bowl to help ignite the large quantity of fuel effectively to build power at that level
 
The radius at the base of the bowl wall is what dictates how the spray pattern will respond to the overall design.
 
Smokem said:
The radius at the base of the bowl wall is what dictates how the spray pattern will respond to the overall design.
Click to expand...


What if the radius from the bottom of the QSB 6.7L bowl angled so that the walls were slightly inward like the automotive 6.7L. Would it be ideal with a wide cone angle?


image_zpszxoksabo.jpg



I think if I got aggressive with timing and 146* come angle I'd spray right out of the automotive 6.7L bowl.

At that point how do you know timing is to high? once it's to late, Boom engine toasted.... I think I'll go with whats working for everyone else.
 
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Running 6.7 industrial pistons with late 5.9 cone angle and nothing but great things to say about it...running timing in the 42-45* area at 5000rpm
 
Thanks for the wealth of info this is a great discussion! Should make a sticky out of it!
I can't wait to build this engine!
 
Is their a certain formula to figure out when you start spraying out of the bowl? I know their are a ton of factors but if their was one for a stock engine then one could plug in their special needs in for their particular engine.
 
What the hell I thought everyone touted the reentrant pistons as the best for performance builds? Or is that only with respect to durability?
 
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