14.5 afr on a diesel is the “ideal” afr because at the end of combustion you are left with no extra fuel and no extra air. That’s a perfect scenario. Getting that good of a mixture In the cylinder is difficult. You’ll generally see haze when the afr hits 15. Anything lower than 15. Will progressively get darker because the fuel is now burning all of the available oxygen and the rest is actually turning into charcoal briquettes. If you light a OXY acetylene torch it has soot particles until you add the oxygen.
I usually see noticeable haze starting at 17 and it’s pretty smoky by 15. Not like can’t see thru it smoky but like a brown column smoky. That is usually the peak power and egt point I have found.
Josh that was an excellent video the information was priceless you passed on your real world experience which will hopefully save us melting pistons 🙂 Can't wait for Thursday's video 🙃 Take care stay safe and God bless you always 🙋♂️🇬🇧
Tanks for your great explaning of various topics its really interesting and I learn very much through your videos. Ive used that knowledge on my own Project an Audi 2.0 tdi im from Germany its really hard to get a dodge cummins here there ether really expencive of trash. Keep up the great work and merry Cristmas
Furthermore at a 14.5 afr you are extracting the most energy out of the fuel. As we know energy is Released forcing the piston down, energy is also released as heat. The “ideal” air fuel ratio is going to have the hottest combustion temperature. Now you can use that information to understand why having lean air fuel ratios decreases cylinder temperatures. You will have extra air in the cylinder allowing what fuel is injected to have a more complete burn. Something similar is true for a excessively rich condition. It will burn all of the available oxygen and the extra fuel is actually cooling the chamber down. It might look bad with all the black smoke but with a limited inducer size you want to use every last bit of oxygen that makes it into the cylinder.
I am a field asset performance optimization engineer for a company that is typically considered the worlds leading industrial engine/process troubleshooting firm. I was a CAT, Waukesha, White, Cooper, Solar, GE mechanic for six years before I went to Texas Tech for mechanical engineering, so have field tech experience to argue with school kids haha. I am newish to diesel platforms, having a 96 12 valve as of March 2020. I spearheaded development of an emission feedback control system using quartz crystals to analyze emission spectrum of exhaust gases immediately post escape event. Paired with dynamic pressure transducers, and velometers for maximum parameter analysis and control. Typically only for natural gas compression, LNG terminals, and power generation. I have been working towards adapting/scaling for automotive diesel applications, but it is really cost prohibitive haha.
@@bcbloc02 sorry I meant off the lean end. I've got no use for smoke. I've gone from 750egt 3psigat 65mph to 450egt 5psi at 65 . With a flog the dog peak/ sustained of 1250 at the top of a long steep grade ( Soldier Summit I - 80 east of salt lake) at 16020lbs ( cat scale)
Love the informational videos just as much as the builds. Maybe a future video could be on external wastegates? Not too much to talk about there but would be cool.
Kind of off topic on the video but just wondering if on your common rail if you could have a post fuel shot at say 90deg crank angle just to knock some temp out and maybe save parts. Probably would increase smoke though. Just a thought.
Thanks for the info. After my engine is built. I plan on making some pulls and seeing how the exhaust looks. If its not cleaning up with turbos I will be looking into a nitrous express kit. Great info on the cooling properties of over spraying. I will keep that in mind if egts get out of line. Sounds like you prefer to set it up to hit based more on rpm than boost presure. 500 rpm or so before peak hp.
@@horsetorquesdiesel I 100% agree. I was thinking having it spray based on boost could lead to some inconsistant results as boost is affected by load on engine. So it could end up spraying way to early. Or late.. probably give you a 2 stroke like power band when the turbos lit though! Thanks again Josh.
Awesome video with tons of tech info about purposes and goals of use. Thanks for sharing the knowledge! Definitely no substitute for experimenting and trying different set ups. Do you have to make a lot of changes based on elevation changes for competition?
Most competitions are at low elevation meaning more oxygen is in the available air at a higher PSIA. Josh's tuning is done at 5892 elevation so when he goes down to sea level it's like giving an extra 5-50hp shot of nitrous, on the other hand if power Driven was to host an event sea level competitors would have to adjust their tune to lean it out to compensate for lacking O2 at elevation and they're only being 12 PSIA ( psi absolute) ambient air pressure. And seeing how turbos do not understand pressure they only understand pressure ratio in: out having a -2 psi start point is a snowballing situation. It's a big factor in why Lenny at Dynamite Diesel wants to know where you're going to drive the truck it'll change what sticks you get recommended to install.
The smile on your face while you described the instant on of coming on on the pipe as the nitrous lights the wick. Now you understand my inspiration and drive I want this from stoplight to stop light I've got a good grin but not the smile you've got. If you want to do lean burn experiments let's have lunch and and have this conversation 3/4 therewith my experiments.(Layton to Cedar City's only 5 hours)
Josh, on the dyno runs and drag racing, once your big kits are on they stay on for the duration of the dyno run, ( short, I know,) and duration of the 1/8 mile or whatever? You ever boost reference as the trigger for the kits coming on? I ask because I know you can get rpm from cam signal but I also know it can be sorta an erratic signal and a big kit coming on too early would suck. thanks
plus there are zero harmful effects of a diesel engine running too lean. eventually it will reach an air fuel ratio that is so lean the engine will make less power but no damage can occur, the opposite of having too much fuel which is bad and causes high egt. which is also the exact opposite for gasoline engines which in their case a too lean scenario causes extreme in cylinder heat and too rich does no harm (to a point, as a gas engine can run sooo rich that youre getting gas past the rings, engine oil smells like gas and therefore can wipe out bearings). for example banks made 1000hp with an l5p at 23:1 afr, but if a small block chevy ran the same afr it would melt holes in the pistons. additionally the measured value of excess fuel or air in the exhaust is called lambda. a lambda of .99 and below indicates all oxygen has been used with an excess of fuel (rich). a lambda of 1.01 and above indicates that all the fuel injected has been burned with an excess of oxygen remaining (lean). and lambda of 1.0 means there is no excess of either in exhaust thus a perfect burn has been achieved, which in theory means engines afr is at the stochiometric ratio for whatever fuel its running on (14.5:1 diesel, 14.7:1 e10 gasoline, 1.7:1 nitromethane, ect)
Two questions for ya: 1- Is there a draw straw in the nitros bottle and if so should the bottle be aligned with valve towards the front of the vehicle so you ensure you are actually pulling liquid instead of vapor? 2- Is the nitros in liquid form all the way through the system until it hits the discharge nozzle?
@@horsetorquesdiesel Cool thanks for the reply, I've built sanitary stainless systems for people that use bottled butane and was very curious if the nitros operated in a similar fashion and if the components were put together the same
I’m gonna be using a Watermethanol kit to inject diesel into the motor and a nitrous kit. What meth jet do you recommend for the diesel? I’m thinking about starting with 500ML to inject about 50/75 nitrous thanks in advance
No where not understanding each other I plan to use the meth kit with out Watermethanol and instead use the kit to inject diesel. That way I don’t have to upgrade injectors or cp3 yet
