Robert P

just make sure you have plenty of smoke all the way thrue the rpm band before using NOS if not you stand a good chance at leaning out your diesel(lack of fuel and too much NOS) and melting your pistons, wade( NGM) is using NOS and i think could help you.

trik396

A lean condition would be bad for a gasser, but it doesn't have any bad effects on a diesel. We run VERY lean at idle all the time. If you don't have the extra fuel to burn, you just won't make any extra power. If you add way too much nitrous the only bad thing that'll happen is you'll snuff out the fire.

Robert P

wrong, lack of fuel and too much nitrous will cause a very lean fuel condition and because the fuel lubricates your pistons and its rings to some degree, it now cant and scuffing or melting will occur, beacause NOS increases EGT's as well by completing the burn, but cools the intake charge. the exhaust event is the one you need to worry about. many diesels have been lost due to to much NOS.

morkable

Well there is no worry about a lack of fuel. I have lots and lots and lots.

Kevin

Robert P

then the only thing you should consider is the drive pressure of your SB62, the best bet is to turn the boost elbow down untill you get to 40 psi then go out and hit the button. this will keep your turbo in it's max effiencency range and you will be impressed.

morkable

You think that I should lower the wastegate? It seems to really like it at the level that I am at. I dont have any egt problems (which correct me if I am wrong is a good barometer to the effeciency of the turbo) Please forgive me, I just want to make sure that I am getting this straight in my head.

Kevin

XLR8R

Please don't muddy the waters here.

Spark-ignition engines run hotter when the fuel/air mixture is LEAN, and compression-ignition engines run hotter when the fuel/air mixture is RICH.
CTDs attain air/fuel ratios as high as 100:1

I hope no one is relying on diesel to lubricate the pistons and their rings to any degree... can you say WASH-DOWN?!

NO2 by itself won't increase combustion temps in a diesel at all; it actually has a cooling effect on the intake charge due to it's high latent heat of evaporation and it's buffering effect on the cylinder temperature & pressure spikes.

We know that plenty of Cummins have been damaged from excessive fueling, but I don't think too many - if any - have suffered from too much air (the two main constituents of which are Nitrogen & Oxygen - same stuff that makes up NO2, or "nitrous oxide" )

Now, Kevin - don't spray any NO2 into your intake manifold if you plan to inject H2O/CH3OH as well! Reasons should be obvious.

The most effective injection point for nitrous is pre-CAC (this has been proven in testing). If you won't run water/methanol, then a small amount of NO2 in the intake airhorn "may" be beneficial... but not IMO. (Why not inject the "extra" pre-CAC?)

Also, I would not lower your wastegate setting. While the turbo may not be compressing air as efficiently at higher boost pressures... hot air is better than NO air! Instead, use the NO2 to recover some of that high-quality (cooler) boost AND force more air (nitrogen & oxygen) into the combustion chambers.
While it's ideal to keep your TIP and compressor outlet pressures close to a 1:1 ratio, you will still be making power when the TIP gets out of hand... don't ask me how I know!

p.s. I love my TIP gauge!

Robert P

if this theory works for you then thats fine, i would add to this but would much rather not aggrevate my carple tunnel.

Robert P

to make this clear
once you have achieved the peak effeciency of your turbo you must keep it there, but when you add cylinder psi (NOS) you must adjust for this--it will raise boost which is going to be hotter than your peak, so lower your boost to compensate for the boost increase and you can make up for lack of air with the NOS. it is better to have a lack of air than to have hot air. why cause hot intake air will melt stuff. also this combo will lower your drive psi because you are lowering boost too. take this for what it is worth. i just hope i have helped

XLR8R

Proven theory + empirical observation = Reality

trik396

Ahhh, the joys of bench racing on the net...

Robert P

obviously our theory works as our one of our trucks is the fastest 305hp CR motor in the country. (NGM) that is reality

morkable

Robert,, just to let you know,, Not to diminish you guys feats! or to disrespect the help that you are providing ( I really really appreciate all the help I can get) But Mike Drevers truck out of Medicine Hat is the fastest 305/555 truck period. He is now in the 10's and mid 11's on #2 all on a single silver bullet. I think he is going to be close to the 10's on #2 by August. Barry has some tricks that he is testing right now.

But anyways back to the topic,

xlr8r, what is the advantage to putting the gas in pre cac? Im not planning on running Water/Meth, (at least not this year, and I do know the reasons I cant run the 2 together at least there)


Thanks

Kevin

XLR8R

The heat-sink effect of the NO2's latent heat of evaporation is much larger pre-CAC, where air temperatures can reach 400*F during high boost, and 200* is ~average. The "differential" is much less on the other side, where the intake airhorn air is typically 5-25*F over ambient.

Also, nitrous injected so close to the cylinders tends to chill the charge-air & combustion chambers enough to cause incomplete combustion... diesels like to run hot.

For those who run twins, it's beneficial to also spray the hot pipe from the top turbo.

trik396

That was my thinking exactly... to inject the nitrous where the air was the hottest... but I didn't want to say anything because I have no real experience with juice and diesels.... yet...

and I didn't want to get told I was "wrong" again...

btw- I'm still going to do something with water/meth and I'll be calling you... just need the funds.. Also I'm doing a similar guage setup on my truck with a piece of aluminum and mounting it to my dash.. Can you tell me what size and type of fastener you used to mount plate to your dash?
Thanks