691 and almost 1400 TQ on 200 Inj's

He called me at 9:00 am I was up in Lakeland Fl. looking for a truck camper for the races.

That truck is loaded with every possible toy you can think of.
 
ralphinnj said:
I asked this question above:

Can someone explain how larger jet size can help if you are limited by the volume of the injector body? That is, these were 200's, right? Which means the chamber can hold 200 cubic millimeters of fuel. Then when you fire, it all gets shot through a nozzle into the combustion chamber. My understanding is that when you run a HUEI injector all out, it sends all of its contents, so I would think that larger nozzles might just reduce atomization and make things worse? Just thinking out loud.

Can someone please explain?

Ralph
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I'll try Ralph, but I am confused if your talking jet size of the NOS or the injector nozzle. I'm sure you know this so forgive me for saying. The left over haze/smoke most are getting is that unburnt fuel due to lack of air. If you add the larger jet, more NOS = More fuel burn't. If you keep upping the jet beyond a certain point your doing no good without adding more fuel. I know my 190's and Beans turbo smokes like a *****, even with an .083 shot. I have plenty of fuel left over.
 
nice numbers and with the inject size being used and nos pill size,if you take into account different dno and different day the dude claiming 755 may not have been as full of it as many thought...
 
but like tim said..he was claiming that with a stock turbo and 190's

it makes a huge difference when those two items are involved..
 
i dont know crap about the inject flow and i didnt read all the posts on the gogo thread or all of these.but i tell you what if you are gonna use nos you will make more hp running stock turbo and lower psi and doing the rest with nos than running an aftermarket turbo and then adding gas.the stocker may not hold for ever but best power can be done with a stocker and i think drive pressures are down so they should last longer
 
I'd love to see drive pressure on a stock turbo with a big shot and injectors.

Adam...why don't you throw a DP gauge in your truck and test that stuff before you put on that new turbo ? It only takes about 20 minutes to hook up a temporary one.
 
Tim, I thought the nozzle size was related to the injectors. Maybe I am the one that is confused. My basic point is that a certain injector has a limit to the HP it can produce. If HUEI injectors are limited to the injector hold volume, then the only thing that can vary is the extent of combustion (as you were saying Tim). If there is haze or smoke, it is not 100% efficiently combusted.

Stepping back, we know that stock injectors with as much NOS as possible maxes out around 480RWHP. That's what I am told, and it sounds about right since we know the stock turbo is more than enough to basically clean up the stock sticks, but we also know that air is not as good of an oxidizer as nitrous, so a little bump from the 430RWHP to 480RWHP by adding nitrous to an otherwise stock truck (assume tune and pipe) sounds about right. That is, I will take it as fact that nitrous with the stock sticks will yield very close to 100% combustion efficiency.

So, if we take the ratio of 200/135, we have 1.48. That means that if we could combust just as efficiently with these larger injectors (which usually you can't, but if you could), a set of 200's should yield as much as 711RWHP. The 691RWHP level works to about 97.2% combustion efficiency, which is believable. On a side note, 190's works to 675RWHP with the same approach, which is why I called BS on the 755RWHP claim. And that 675 number assumes 100% efficiency, which they will not have as you will see below. I still say BS.

As you stuff more fuel into the chamber, it becomes harder and harder to burn it all. That is just physics. We should expect a slow, but steady decrease in combustion efficiency as we go to larger and larger injectors. We can estimate the loss in efficiency, if we assume it is linear for the injector sizes we have data for. That is, let's assume that stock sticks (135 mm^3 per stroke) gives 480RWHP and call that 100% combustion efficiency, and that 200's yields 691RWHP. We can create a simple equation as follows:

Burn Efficiency = 105.8154 - (Injector Size in mm^3/stroke)*0.04308

Sorry, this is the engineer in me coming out. But it makes sense. If we apply this formula, we can predict what the maximum RWHP will be for various injector sizes:

nozzle efficiency RWHP

135 100 480
160 98.9 563
185 97.8 644
190 97.6 660
200 97.2 691.2
225 96.1 769
275 94.0 919
345 91.0 1116
430 87.3 1335

Now all of this assumes the efficiency loss is linear. It probably is not, but it is a start and the numbers are not that crazy. This formula already takes into account drive train losses, so I think it should be ok unless those change in percentage.

Thoughts?

Ralph
 
Ralph I dont have time to read thru that whole post but. On a 6.0 you cannot tune the pulsewidth directly. Therefore you have to size the nozzle to flow said amount within the same pulsewidth. Somewhere in the 2.0 to 2.6ms range.
 
bones said:
how does ambient air temp and turbo cfm play into this equation...
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Ummm if the air is colder then it is denser. Thus when it goes through the compressor you get a higher eff. out of it. Higher efficiency translates to more boost because the air is already denser than at ambient temp. When the compressor does work on the system it will raise the temp of the air, which is why we have intercoolers. CFM would be the base part of trying to estimate all that is being done here. You kind of need to know what the max volume of air a compressor can do work on to estimate how much more NOX you would need to completely burn whatever unit of fuel your shooting for.
 
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But nitrous is injector after the intercooler before the intake manifold. So by that time alot of the heat is gone.. or so i would assume. I'm not sure what the eff% is of a 6.0L through the intercooler.
 
UNBROKEN said:
I'd love to see drive pressure on a stock turbo with a big shot and injectors.

Adam...why don't you throw a DP gauge in your truck and test that stuff before you put on that new turbo ? It only takes about 20 minutes to hook up a temporary one.
Click to expand...

where can I get one?
 
It's just a boost gauge...nothing more. Tap your manifold or remove your pyro probe....you'll need a standard 1/8npt threaded fitting. Get some copper Auto Meter tubing from any parts store and attach the tubing to the hole...it comes with the right fitting...then attach the regular plastic tubing to the copper tubing and then the gauge.
Hell...for the test you don't need to hook up the electrical on the gauge...hook it up and zip tie it to a wiper arm or something.
 
make one. 80-100psi boost gauge, then use 1/8" copper tubing from your exhaust manifold. Just like your pyro. probe.
 
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