Performance 6.5 Injectors

[JeepSJ]

Check this out

It appears all else being the same a larger nozzle will create a larger "flame" or more penetration is what it actually references. Maybe better overall combustion with higher fuel rates or better heat distribution into cylinder? Don't know if anything is measurable as far as power/performance but the image appears like there is a difference.

I hope this link works because I doubt I could find it again.

http://public.ca.sandia.gov/ecn/orifice.php

That is a very cool link. It is interesting to see the difference in the spray/flame pattern at different temperature and pressure and nozzle size. Based on that, I'd say that bigger nozzles and higher pressure are a good thing as you increase boost. The higher cylinder pressure has a significant affect on the spray pattern and penetration, and the bigger nozzle with higher pressure would compensate (at least partially) for that.

[AndyL]

136Mpa = 20,000PSI, defiantly common rail. For the 6.5 application I don't believe comparing a 2000psi injection event to a 20,000psi is apples to apples. But then again I can't find my Fluid Dynamics degree laying around either!!

I was hoping for some evidence against the mythical "Performance High flow Injectors."

[JeepSJ]

136Mpa = 20,000PSI, defiantly common rail. For the 6.5 application I don't believe comparing a 2000psi injection event to a 20,000psi is apples to apples. But then again I can't find my Fluid Dynamics degree laying around either!!

I was hoping for some evidence against the mythical "Performance High flow Injectors."

We are not comparing 2000 to 20000 here. All this is showing is that with an increase in fuel pressure there is an increase in flame penetration into the chamber.

[Hubert]

I thought the link was pretty good and does support at least a little credibility for different injectors for the "marine" application. 6.5 pressures are a lot lower and IDI is a different animal but I think the link does show fair comparison for nozzle size. It references penetration rate of fuel and flame front into cylinder. I did not see any documentation of any power differences but does show there is a difference in spray pattern/combustion to nozzle size.
It has always struck me that marine injectors/nozzles are OE name brand parts at least from all the reading I think they are OE for marine applications. We are not talking some joe injector shop marketing his modified injector. Is the HP rating of marine engines higher? I have assumed they are and thought the pump was turned up and engine set for more HP since adequate cooling could be guaranteed with the application. Combined with the fact economy is less of a concern with recreational applications and emission requirements are different too.

Like posted earlier several times it does not make sense to me that just changing injectors will give any appreciable HP gain. But after viewing link I think it can definately be argued injector differences can be matched for application ie I think marine injectors are better for steady hi RPM operation and or maybe higher fuel delivery. And then maybe not necessairly for anything other than better emissions. HP gains are probably due to IP fuel delivery increase only.