Car going pig rich on nitrous

[Silver2002ta]

Got a question for you all and im trying to figure out if its my tune or not. I tuned it SD. I am running a 125 shot when I launch the car & halfway through 1st gear my a/f is around ~11.8-11.9. Once the car gets into 2nd gear it goes pig rich 10.7-10.8. On motor my tune is perfect 12.6-12.7 through the rpm's and up top around 12.9. Part of me wants to think the wideband is off (I recalibrated it) but its showing to read right when its not on the bottle. Also there was never a problem with the a/f on nitrous up untill a couple weeks ago like somthing changed the car. I mix some 116 in with pump gas for extra insurance. I have changed the fueling accordingly for w/ running the good gas in there. I'm out of ideas to look for. Any clues?

[69lt1bird]

post your tune file

[spike]

do you always log ur nitrous runs with the wideband. Do u have previous logs. Im wondering if this is normal since a wet kit always runs fat specially during the lower rpm gear shift when the engine is not utilizing as much fuel.

[Silver2002ta]

Here is a log where it is crazy rich on spray. Part of me wonders if the wideband is jacked. I watch it while I am racing and never see some of the #'s it shows datalogging like the 18.9 afr otherwise id get out of it. I also have a ton of timing out for safety. And also remember at one point in time not too long ago the afr's on spray were all in the mid to high 11's up top but somthing made it start going fat up top and I am not sure what. Thanks

[Cantalope Kid]

Ve table needs some smoothing down low. I say its all in your nitrous fuel. Jet down.

[Dragman]

I am also SD open loop. I run my VE table the same for each row 95 thru 105 KPA. I also always want my VE - AFR error to read -9 so u might not be super rich. Thanks Mike (WS6FirebirdTA00) for that one! Need to make me a new histogram so its will be 0s for 12.0 AFR. Its not going to be zero's because that would be the PE command # u had without bottle. I try to get about 11.8 to 12.2 with the hose. Looks like in ur histogram u are alittle lean in some area's like I think u had some -2s. Of coarse this is if ur wideband is spot on.

I would make sure ur jets are picked correctly. Might even check to see if filter is stopped up on NOS side. I have had that happen once myself. Looks like u are logging to many pids I would lower them & u should get more frames per sec.

[Dragman]

Another question does AFR wideband match what HP Tuner scanner says??

[Silver2002ta]

I am also SD open loop. I run my VE table the same for each row 95 thru 105 KPA. I also always want my VE - AFR error to read -9 so u might not be super rich. Thanks Mike (WS6FirebirdTA00) for that one! Need to make me a new histogram so its will be 0s for 12.0 AFR. Its not going to be zero's because that would be the PE command # u had without bottle. I try to get about 11.8 to 12.2 with the hose. Looks like in ur histogram u are alittle lean in some area's like I think u had some -2s. Of coarse this is if ur wideband is spot on.

I would make sure my jets are picked correctly. Might even check to see if filter is stopped up on NOS side. I have had that happen once myself. Looks like u are logging to many pids I would lower them & u should get more frames per sec.

You know a friend mentioned this also said somthing might be going on with the solenoid like debris or somthing. Heres another thought I am trying to keep the car safe as possible I have a TR8 in there. I did go from 7's to 8's is it possible the plug is too cold? The guy that is doing my jetting is a long time friend of mine that works at Nano Nitrous if any of you have heard about them. Their business is about 10 mins from me. He did my jetting for 75/100/125 and the afr was all where it needed to be untill just not too long ago. I will check this solenoid out

[Silver2002ta]

Another question does AFR wideband match what HP Tuner scanner says??

Yes. But when I am watching it I never see the ones that say like 18+ afr otherwise i'd kill it. I dont know if its false or what I think in that log it only had that count once. I'm just confused how the afr is where I want it through 1st gear then just goes rich rest of the way

[Dragman]

Yes. But when I am watching it I never see the ones that say like 18+ afr otherwise i'd kill it. I dont know if its false or what I think in that log it only had that count once. I'm just confused how the afr is where I want it through 1st gear then just goes rich rest of the way

I would think the 18 AFR is either false or a spike in data as it is only 1 frame count. Would guess u need to tune VE closer on NOS maybe because u change to higher octane fuel.

U can PM me we can talk or compare notes!

[Dragman]

Did u get to try out car yet??

[silverzz28]

You know a friend mentioned this also said somthing might be going on with the solenoid like debris or somthing. Heres another thought I am trying to keep the car safe as possible I have a TR8 in there. I did go from 7's to 8's is it possible the plug is too cold? The guy that is doing my jetting is a long time friend of mine that works at Nano Nitrous if any of you have heard about them. Their business is about 10 mins from me. He did my jetting for 75/100/125 and the afr was all where it needed to be untill just not too long ago. I will check this solenoid out

Your plugs will not cause this. I would check out your system 1st. BTW I would get those projected tip plugs out of there for nitrous

[gold98Z28]

what was your bottle pressure befor and after the runs?


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[Cantalope Kid]

I recommend TR6's. My shop recommends TR6's for an entry level shot like yours (i.e. +125hp). TR8's are overkill in my opinion.

[jmm98LS1]

TR6's are a step colder, but they're still a projected tip plug---not a very good idea with nitrous. Just because lots of people run them on smaller shots doesn't make it right. Nothing wrong with a -8 plug in this app, they'll just foul quicker. No such thing as "too cold" of a plug with nitrous.

OP: Gold98 asked a good question, what are your bottle pressures before/after the run? Most importantly, have you pulled any plugs after a run? Your plugs are going to tell you a more accurate story than your wideband. Pull a few and see what the fuel ring looks like, I'm betting you need to jet down a bit on the fuel side. Also if you don't already have a nitrous filter, get one.

[Dragman]

I also use TR6s with no issues. Sure is alot of LS1 car's using them with nos.

[vortec]

if you are running a 125 shot only then I would get TR6 plugs,you are running way to cold a plug for that shot.
The lean spike is when the nitrous hit,there are tables in the PCM to get rid of that lean spike on the initial hit!!

[Cantalope Kid]

Tr-6 is "THE" plug of choice over on Ls1tech.com nitrous section. Not sure why it was over looked or shunned in this instance. Figure their (Threads: 986,921, Posts: 10,464,410, Members: 149,669) could be wrong?

[Dragman]

if you are running a 125 shot only then I would get TR6 plugs,you are running way to cold a plug for that shot.
The lean spike is when the nitrous hit,there are tables in the PCM to get rid of that lean spike on the initial hit!!

Could be spike if that when he hit the jug but real hard to get a real handle on what happen when he is only getting 4 to 5 frames per sec. If it is spiking like that he better get a longer NOS line or shorter fuel lines. I agree with TR8s being to cold. He needs to make some adjustments and see if wideband is correct. Then give some more feedback.

[Dragman]

I sent him some changes to make to VE table now he said has a Rocket Ship!