Well I finally got my fuel system up to the task & hit it with a 100 dry shot today. It went lean as hell, in the 14's. I indexed the nozzle towards the maf then away, it didn't seem to help although I noticed that the IAT sensor lowered significantly when it was pointed away. When it was pointed at the maf I saw now temp difference. My single nozzle is installed like this:


I am considering doing a PE vs IAT to get this on the road. Maybe my tune is so far off that the MAF can't compensate? My commanded AFR is at 11.7 at naturally aspirated WOT but is running right at 13.0 actual. This is a 01 with cam/exhaust, descreened MAF, lid etc.

Robert can you give some advice? I am not above using a separate rich tune as this is a toy only car & I can handle only going WOT on the bottle.

 

I would look into why the car only goes 13:1 when your programmed to go 11.7:1, that is good starting point.
Have you tested the nitrous flow with the car off to see how the plume is?
Tried it w/o a filter? My filter freezes which causes a rich as hell condition, luckily and not lean as hell. Freezing the MAF should also cause it to go lean as hell, unless someone played with MAF Failure the wrong way?

 

Is that a 90* nozzle or a straight nozzle. That location may work better with a 45* nozzle to aim more directly at the maf. This location with straight nozzles works best with one on each side and meeting in the middle. A 90* in that location just dosen't normally work well. If it was my set-up I would use 90* in the neck pointing right at the maf (look in my web on how the vararam is plumbed). However, like cat said, find out why your not getting your commanded wot a/f when n/a let alone on the spray, as things may not be as bad as you think. Hope this helps some.
Robert

 

It looks like a "bird mouth" so I think it is a 45. I didn't think that the commanded afr being different that the actual afr was a big deal while in WOT. I know it wasn't right from the factory.

Thanks for the help, I'll keep playing with it until it is right.

 

I wasn't aware there was a table for PE vs IAT.
Could the PE be turned off for some reason? is this a completely stock calibration in the PCM?

Oh yeah in any case I would reclock that MAF 90* clockwise.

 

There is fuel modifier tables vs. IAT, and spark also on 02' and I think 01's. I know 98-00 did not have that.

If you modified the vehicle and the fuel trims weren't in-line it may have not corrected itself to the commanded, however, I would think that the pcm would throw in extra fuel since it was commanded, not pull fuel. Too add fuel you'd have +LTFTs, and if you didnt then the fueling at PE would lock out at '0' adder. I have to think that someone tuned the car before, and maybe messed up on some of the tables, that the only reason I can think of for the fueling to be so far off NA and again repeated on Nitrous.

 

Are they base modifiers or PE-only?

 

It's the stock tune + correct IFR's, rasied rpm limit & few deleted DTC's. I have added injectors, 224 cam. LT's/ Td's & lid. It runs good at cruise & gets good gas mileage, stays around the high 14's to 15's for AFR. I was hoping to get the WOT in line and be done.

It's an 01 & I have the IAT PE. It seems to take a little while for the IAT's to drop significantly when hitting the nitrous so I don't think I will use this PE. It's so cold here that I don't know if I could dial it in correctly.

 

okay then it's not a stock tune. You should probably take it back to your tuner to get straightened out.

 

Well I guess you're right, it's not a stock tune , but I am the only tuner within 600 hundred miles or so. I am the one who did the tune so far so I will have to get it right.

 

You said you basically just changed the IFR and that it was correct. Perhaps it's not correct.
Was the MAF table changed in any way?

 

code, what does the PE table look like? if you want, shoot me a copy of your tune to: cat3n4@gmail.com I can look at and see if there is something out of whack maybe by assident.
When looking at the PE, you have the PE mulitplier table, then the parameters that kick PE in, MAP, TPS etc.. Have you verified that your seeing 100% TPS? What about the FTC, are you indeed in PE mode?

 

Sorry I am so uneducated about this, I just started on using hpt. The injector IFR is correct. It ran exactly the same with the stock injectors.

The car is running great, it sees approximately 13.0 AFR under WOT no knock etc. Everything is stock as far as the VE, MAF Tables, & PE vs RPM.

I am working on a different tune with the PE Enable RPM set to 0 & enrichment rate set to 2 and adding PE vs RPM.

The only question was that why is it that when in PE it is commanding 11.7 to 1 AFR but only getting 13.0? Is this my problem with the dry shot? I'm not sure how to send my tune, I will give it a shot. Thank you for your help.

 

Take the tune you currently have and send as an attachment in an email. It should be "yourtunefilename.bin" I can look at it when I get off work, about a couple hours.

You shouldnt need to mess with the settings you mentioned. I only adjusted the PE table to relfect a nice pretty curve, richer to peak torque and leaned it out some for peak hp and immediately shot it back up to richness after in case I miss the shift or something, yeah its a reverse manual valve body, so w/o the shift light installed yet I run it by ear.

I'll look at the tune and give you pointers, if I adjust anything at all, I will list each activity for you and you can use the compare feature when I send it back to see for yourself the differences.

Charlie

 

Do me favor, or yourself... Can you get a short WOT (or long one if you can)log with the following parameters:

RPM
MPH
Advance
KR
MAP kPa
MAF Hz
B1 O2's
LTFT's
FTC
IPW

That should provide pretty decent information.

 

Sent both, thanks again. From sbaker@montanasky.us

 

Got both, looked at the log. Looks normally abnormal, the AFR is off, but nothing is popping out at me.
Just got off the phone with my buddy Wayne who has 01, I will look at it tomorrow afternoon and shoot you something back.

 

Thanks, I may do some more logging in the next couple of days. I may just switch to a wet kit.