I know it is sematics, but shouldn't we say, "advance ignition"?
That way "timing" is reserved as a tuning parameter, no misunderstanding
.
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Nitrous basics
- Thread starter Diesel power
- Start date
I know it is sematics, but shouldn't we say, "advance ignition"?
That way "timing" is reserved as a tuning parameter, no misunderstanding
.
I was under the impression that it did advance ignition, much like boost does. But I will give this more of a look. I see what you are saying about reduced charge temp. However, from earlier discussion, that appears to be offset with the heat of formation released upon decomp. leaving a hotter charge with more O2---> each advances ignition. Just thinking on the theoretical, don't throw rocks guys.
Based on what the my truck feels like today, still early in tuning, i think a good place to start will be in the teens in timing terms.
Working my way up. It's conjecture on my part and frankly a guess. But it "feels" like thats the place to start with about a 050.
Working my way up. It's conjecture on my part and frankly a guess. But it "feels" like thats the place to start with about a 050.
It was requested that the thread be cleaned up to remove insults in a tech thread. I did a fast cleanup, and I or a staffer will go through it later to do a better job.
I found a significant reason for higher heat output than the usual heat calculations. Nitrous has a 55% higher density than air. This, by itself, will account for more cylinder compression heat, early ignition, and the need for timing retard.
http://www.sorac.org/hybrid_cd/Propellant Info/Nitrous Oxide.doc
In reality, this density increase is responsible for more oxygen than the molecular impact. 55% is analogous to being an 8 psi turbo charger, with none of the usual turbo negatives. (Assuming undiluted nitrous)
air=.074 lb/ft^3
nitrous=.115 lb/ft^3
http://www.sorac.org/hybrid_cd/Propellant Info/Nitrous Oxide.doc
In reality, this density increase is responsible for more oxygen than the molecular impact. 55% is analogous to being an 8 psi turbo charger, with none of the usual turbo negatives. (Assuming undiluted nitrous)
air=.074 lb/ft^3
nitrous=.115 lb/ft^3
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Correct, with a givin amount of fuel and air flow in and out......
thus creating the need for more exhaust flow.....
The bottel neck or lack of flow will show with DP and EGT readings......
With my testing, after this point adding more nitrous after exhaust was addressed netted more power and cooler EGT's.
removing exaust restriction would have lowered egt's wether nitrous was involved or not , so what was the redution in egts after the exhaust restrictions were removed on fuel only and with spray ? and what was the nozzel size ?
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On fuel everything was fine.....after adding the nitrous the DP and EGT's got a bit too high, i then adjusted what i thought would help out accordingly, and it did.
on fuel i lost some spoolup with a looser housing.
Just two .060 jets made that much difference
My EGT's were fine on fuel,i added nitrous it got hot,i then made exhaust modifications, the egt's droped, i then added more nitrous, the egt's dropped futher......I made a breakdown a few pages back on exactly what difference everything made.....i'll look for it.
I agree, but i was thinking beyond the fuel, and such as you described.
Yes typically you can see higher heat due to initial nitrous use, Heck i did too, i saw over 2000*, then i realized i had a exhaust restriction, put a better flowing manifold on and a 2CM bigger exhaust housing with a bigger wastgate and i droped the boost from 60 to 50lbs, DP went from 103 to 55 ish and my egt's went down 300*.
After that i added more nitrous about a 0.030 increase on both stages and walla i got another 100* drop!!!!
Then i added the nano system to my truck and the power went up a bit 2.5 tenths faster and the EGT's came down about 50-75*
There ya go, my life story.....
Here ya go trentnell
I don't think it would be an advantage. Many people can tune their DP to almost 1:1 with wastegated turbo's thus dropping egt's.
SO
Diesel Power, you dropped 300* by changing the turbo housing, with no other changes then? Allowing for more NOS right? Did you gain some of those egt's back with a bigger shot?
Kind of the same idea as removing the stock exhaust and downpipe and dropping egt's as well then I guess-which makes sense.
The only downside I see is the spool up lag probably which could be a PIA for street trucks but probably fine on a track truck I guess.
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Ok, as long as some smart people are here I have a few questions about nitrous. Last summer I ran on a dyno. I ran a tune that made 450 on fuel 480 with water/meth and 548 with water/meth and a .55 shot of nitrous. Can you safely run water/meth and nitrous? The tune ran 28 degrees of timing. Do I have to worry about chamber pressure? or what are some guide lines when running this type of setup?
I am going to throw in a suggestion. Nobody disputes that nitrous has made it easily possible to destroy motors quicker. This would imply that it very well could be implimentation that is to blame, and not nitrous, just one possibility, but it hasn't been disproven to my satisfaction . It is clearly a 2 camp discussion. What would be really good to determine:
2 configurations
1. High boost, high fuel configuration, typical reputable 450 HP tune.
2. Normal boost (or thereabouts), high fuel tune, retarded timing with N2O, again approx 450 HP.
Determine which one generates higher peak CP, and EGT. My guess is that #2 will come out ahead. I could be wrong.
. It is clearly a 2 camp discussion. What would be really good to determine:2 configurations
1. High boost, high fuel configuration, typical reputable 450 HP tune.
2. Normal boost (or thereabouts), high fuel tune, retarded timing with N2O, again approx 450 HP.
Determine which one generates higher peak CP, and EGT. My guess is that #2 will come out ahead. I could be wrong.