View Full Version : ls1 nitrous question
cjmatt
10-10-2009, 04:16 PM
i pulled the jets out of my car today, they were a 55 nitrous and a 31 fuel. can anyone tell me what size shot this corresponds to?
BB71Mopar
10-10-2009, 05:44 PM
That should be about a 125hp shot.
cjmatt
10-10-2009, 06:00 PM
That should be about a 125hp shot.
ok cool. i found a couple calculators that say the same, but its seems like its a little rich for the higher fuel pressure on the ls1, explains alot of my rich condition
99slverZ
10-10-2009, 06:30 PM
What brand of kit? If its a kit specifically designed for the LSX a lot of companies compenstate on the jetting side for the higher fuel pressure. Also what bottle pressure do you spray at? Pulling at timing? Mods?
1BADAIR
10-10-2009, 08:11 PM
most are like 52/28 -100 and 62/33-35 for 150
http://www.coldfusionnitrous.com/calculator.aspx
Good baseline jettings. What leads you to belive the engine has a rich tuneup ? Not that I doubt you, I am simply curious as to your reasoning.
cjmatt
10-12-2009, 09:26 AM
http://www.coldfusionnitrous.com/calculator.aspx
Good baseline jettings. What leads you to belive the engine has a rich tuneup ? Not that I doubt you, I am simply curious as to your reasoning.
well, when it was on the dyno, itd blow black smoke as soon as you hit it and burn your eyes from the raw fuel in the air. Plus I didnt have a pressure gauge on the bottle until this weekend, and it was about 600psi. I didnt realize how long it takes the bottle heater to actually warm up a bottle to 900. I heated it up just to see what itd take and it took alot longer than I had ever ran the heater at the track. Every time ive sprayed it, i was probably around 600 or so. Also, when I dynoed it, it only gave me about a 60hp increase. Plus, according to your calculator, I should have a 28 jet and ive got a 31 in it right now
1BADAIR
10-12-2009, 09:39 AM
what kit?
nos uses 51/31-100 55/35-125 i believe
cjmatt
10-12-2009, 09:59 AM
what kit?
nos uses 51/31-100 55/35-125 i believe
I believe its just a generic NOS universal kit. The guy I got the car from was a big time Kentucky street/drag racer. Hes been on pinks a few times, has a bunch of cars, all on spray. Im sure he just threw it together with parts he had laying around. Its all hidden, so alot of the stuff was done on his own. Ill go check what solenoids its got on it when I get home. Ive only seen them once as their buried in a fender
well, when it was on the dyno, itd blow black smoke as soon as you hit it and burn your eyes from the raw fuel in the air. Plus I didnt have a pressure gauge on the bottle until this weekend, and it was about 600psi. I didnt realize how long it takes the bottle heater to actually warm up a bottle to 900. I heated it up just to see what itd take and it took alot longer than I had ever ran the heater at the track. Every time ive sprayed it, i was probably around 600 or so. Also, when I dynoed it, it only gave me about a 60hp increase. Plus, according to your calculator, I should have a 28 jet and ive got a 31 in it right now
I thought the jetting looked rich. I didn't run it through a claculator to look either. Smoke and nitrous equals piston fialure most of the time so I'd get that fixed and soon.
with nitrous consistency is everything.
Same bottle pressure fuel pressure etc. Without it your going to create alot of problems for yourself.
BB71Mopar
10-12-2009, 02:08 PM
Smoke and nitrous equals piston fialure most of the time.
Is this your method of tuning..
Explain how this would be a failure? Just because a car is a little rich doesn't mean it is going to have a piston failure. Piston failures occur when there is detonation and or excessive heat or an object impacting the piston.
It is always safer to run the fuel a little rich when you are not sure about it. It is easier to put fuel in the vehicle than an engine.
cjmatt do you run a wide band o2 at all?
CableGuy
10-12-2009, 02:51 PM
Is this your method of tuning..
Explain how this would be a failure? Just because a car is a little rich doesn't mean it is going to have a piston failure. Piston failures occur when there is detonation and or excessive heat or an object impacting the piston.
It is always safer to run the fuel a little rich when you are not sure about it. It is easier to put fuel in the vehicle than an engine.
cjmatt do you run a wide band o2 at all?
:shake:
Even this "ricer" knows your wrong. I guess you need to know that kinda stuff when your making 140hp per cylinder....
Also note what I bolded, and think about it.
Hint, a little rich is what I ran, 10.8:1 and still a tab bit of black smoke would come out on spool, therefor......"???"
BB71Mopar
10-12-2009, 02:56 PM
:shake:
Even this "ricer" knows your wrong. I guess you need to know that kinda stuff when your making 140hp per cylinder....
Also note what I bolded, and think about it.
Hint, a little rich is what I ran, 10.8:1 and still a tab bit of black smoke would come out on spool, therefor......"???"
No explain!
CableGuy
10-12-2009, 03:19 PM
No explain!
You seriously don't know that once you get to a point of being too rich, you are in the same ball park as being too lean? (Actually could be even worse.)
BB71Mopar
10-12-2009, 03:29 PM
I know a guy that went down the track with the nitrous solenoid wire broke off trying to spray the whole way down. Did not damage the motor at all. And what part of that is PISTON??? That world be washing the cylinders causing RING failure.
My car runs rich as hell and I have no damage done to it. I prefer to run it rich. That way I drive home instead of walk.
CableGuy
10-12-2009, 03:41 PM
You might not see it as often on a N/A / blower car, but...So you wash the cylinder down, mis-fire a couple of times now you have a pool of fuel in the cylinder along with what ever is in the air, exhaust valve opens, and your now down past the 1/8 and the manifold are starting to turn orange. It Detonates, but in a very bad way. Hopefully you can figure out what I left out.
On a turbo car you can and will see this. Exhaust contamination is another thing you gotta look out for even when running a normal 12:1 on a turbo car if you don't know what your doing. This is the same idea, but instead of contaminating it you, are igniting it.
BB71Mopar
10-12-2009, 03:54 PM
So what part of this thread mentioned TURBO???
Is this your method of tuning..
Explain how this would be a failure? Just because a car is a little rich doesn't mean it is going to have a piston failure. Piston failures occur when there is detonation and or excessive heat or an object impacting the piston.
It is always safer to run the fuel a little rich when you are not sure about it. It is easier to put fuel in the vehicle than an engine.
cjmatt do you run a wide band o2 at all?
On nitrous Rich is bad. On any other power adder Rich is fine. If you'd like to come by I have a few ashtrays I can show you that were made from being to rich.
The problem as least as has been thoerized by many,Makes alot of sense, is that on nitrous and fuel gets into the ring land. Normal air doesn't carry enough oyxgen to light this fuel.however nitrous does.
You have to understand normal air is
%18-20 by volume of oxygen depending on altitude
nitrous is 30% oxygen by volume.
when the nitrous disassociates at around 450 F it can create a highly oxidzed zone down in the ring land. Now there isn't just gasoline on that ring either. There is also oil. So once the fuel gets under the ring it lights and cuases the ring to unseat and then oil gets by the ring and the nitrous combusts the oil.
Result burned,melted pistons and engine fialure. With smaller loads of nitrous 40,50,75 hp on a v8 the risk from over rich is minimal. Start shooting 175-200-250 and it gets critical to have the NF or Nitrous to Fuel ratio correct.
One of the other problems with rich nitrous tune ups is that they tend to want more timming. So if you put in enough timming to burn off the fuel to kill the smoke the plug always shows undertimmed which makes it easier yet to setup a scenario of detonation.
If Matt would post a plug picture with the thread portion cutoff it would go a long way to determing if the tuneup is really overich or if there is some other problem going.
You might not see it as often on a N/A / blower car, but...So you wash the cylinder down, mis-fire a couple of times now you have a pool of fuel in the cylinder along with what ever is in the air, exhaust valve opens, and your now down past the 1/8 and the manifold are starting to turn orange. It Detonates, but in a very bad way. Hopefully you can figure out what I left out.
On a turbo car you can and will see this. Exhaust contamination is another thing you gotta look out for even when running a normal 12:1 on a turbo car if you don't know what your doing. This is the same idea, but instead of contaminating it you, are igniting it.
Missfires can hammer the shit out of a motor.
Ring washdown could also cuase some oil contamination in alot of cases as well and oil in the cylinder with nitrous equals massive fial.
Agreed.
cjmatt
10-13-2009, 10:55 AM
On nitrous Rich is bad. On any other power adder Rich is fine. If you'd like to come by I have a few ashtrays I can show you that were made from being to rich.
The problem as least as has been thoerized by many,Makes alot of sense, is that on nitrous and fuel gets into the ring land. Normal air doesn't carry enough oyxgen to light this fuel.however nitrous does.
You have to understand normal air is
%18-20 by volume of oxygen depending on altitude
nitrous is 30% oxygen by volume.
when the nitrous disassociates at around 450 F it can create a highly oxidzed zone down in the ring land. Now there isn't just gasoline on that ring either. There is also oil. So once the fuel gets under the ring it lights and cuases the ring to unseat and then oil gets by the ring and the nitrous combusts the oil.
Result burned,melted pistons and engine fialure. With smaller loads of nitrous 40,50,75 hp on a v8 the risk from over rich is minimal. Start shooting 175-200-250 and it gets critical to have the NF or Nitrous to Fuel ratio correct.
One of the other problems with rich nitrous tune ups is that they tend to want more timming. So if you put in enough timming to burn off the fuel to kill the smoke the plug always shows undertimmed which makes it easier yet to setup a scenario of detonation.
If Matt would post a plug picture with the thread portion cutoff it would go a long way to determing if the tuneup is really overich or if there is some other problem going.ill pull a plug, but i think you guys are blowing this thing outta proportion, the car doesnt run that rich, you cant see smoke on the street, it just smells a little rich and theres some smoke when you dyno indoors. I ran an 11.17 shortshifting the car on probably 600 psi in the bottle
ill pull a plug, but i think you guys are blowing this thing outta proportion, the car doesnt run that rich, you cant see smoke on the street, it just smells a little rich and theres some smoke when you dyno indoors. I ran an 11.17 shortshifting the car on probably 600 psi in the bottle
Nitrous is dangerous. My advice was to cleanup the tuneup. Some people were acting like a ass though.
Stable bottel pressure, fuel pressure etc and a good system of routine will keep your nitrous motor alive and happy for a long time. Smoke on the dyno is bad. Trust me on this one. I don't care if its rich off the spray as long as its good on the spray. Last motor I saw make smoke on the dyno on spray was running a 200 shot and it ate a slug.
That was the michiganspeed pinks car.
mikesfastss
10-13-2009, 01:24 PM
Nitrous is dangerous. My advice was to cleanup the tuneup. Some people were acting like a ass though.
Stable bottel pressure, fuel pressure etc and a good system of routine will keep your nitrous motor alive and happy for a long time. Smoke on the dyno is bad. Trust me on this one. I don't care if its rich off the spray as long as its good on the spray. Last motor I saw make smoke on the dyno on spray was running a 200 shot and it ate a slug.
That was the michiganspeed pinks car.
And this is why I took the nos system off my car I want 2 keep drivin it,lol
CableGuy
10-13-2009, 01:27 PM
So what part of this thread mentioned TURBO???
It can happen anywhere... N/A with a mild cam with overlap. (That is a mild cam OR BIGGER)
BB71Mopar
10-13-2009, 10:20 PM
It can happen anywhere... N/A with a mild cam with overlap. (That is a mild cam OR BIGGER)
why don't you go play with your turbo...
CableGuy
10-14-2009, 01:19 PM
Some people were acting like a ass though.
Nuff said...:thumbsup:
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