Btw, I noticed when I was playing with the bi-directional controls today, that 28 degrees of timing in Park gives me my commanded idle RPM. 32 was too much... pushed it up to 1200 where it drops to 22 in the table.

I don't need that much timing... at least with no load. I'll have to see what it does with the a/c on. My IATs climbed into the 150s so I had to stop tuning for the day and didn't get to see.

 

For the tuners out there: I had to add fuel to the afterstart enrichment and lean the VE table like that to get it to work right. What's the likelihood my injector data is hosed?

I think that would account for me having to change so many parameters for it to behave...

 

Okay, a couple of developments today:

I had an interesting conversation with Geoff Skinner @ EPS since I bought the cam from him. He's a pretty good tuner. He said that he's never had to mess with the enrichment tables before. He said if the injector data is good, then it shouldn't need that. He said so there's either a mechanical problem or the injector data is bogus. He recommended I grab some LS3 injectors (since we have good, known data for it) and install, reflash with the good data, and then see.

I was about to pull the trigger on that, but FIC usually provides pretty good data. So I went back and looked at their spreadsheet and made sure everything was correct in the tune.

And holy ****, I'm an idiot.

I didn't even notice this little disclaimer:

All IFR data listed is noted in the filename. 3 Bar = 43.5psi ; 4 Bar = 58psi
To go from 58psi to 43.5psi, divide by 1.1547. To go from 43.5psi to 58psi, multiply by 1.1547.

Care to guess what the filename says? 3-Bar.

So I failed to multiply the IFR data by 1.1547. It changed the IFR data from this to this:
54.3784 54.8744 55.3085 55.8045 56.1765 56.6106 57.1066 57.4786 57.9127 58.2847 58.7808 59.2148 59.5868 60.0209 60.3929 60.8269 61.1989
62.8111 63.3691 63.8652 64.3612 64.8572 65.4153 65.9113 66.4074 66.9034 67.3994 67.8335 68.3295 68.8256 69.3216 69.7556 70.2517 70.6857

I think that would have a huge impact on the car.

I will upload this tune tomorrow and return the fueling tables to stock. I'm sure that's why my VE table had to be leaned out so much. The car thought 60lbs was being sprayed but actually 70 was. Why it didn't light off like crazy is still bizarre. Guess we'll see.

Edit: I've rescaled my VE table by that 1.1547 number. I was spraying a 70lbs injector and the computer thought it was 60, so I had to take 15% fueling out of my VE table to get it to work at the correct A/F. Now I'm adding that back in with proper injector data... otherwise I think I'll be really lean when I crank the car. I want to avoid that.

 

I did the same damn thing on mine with the fic 80lbers.

 

I'm hopeful that my IFR data being off 15% is why cold cranking was an issue, warmup was a problem, and overall stability would go out the window with accessory loads. I was tuning and bandaiding a core issue with the car with a huge variable in play.

 

Sorry, I even looked at your injector data, but mostly concentrated on the "Offset versus Volts" due to your starting problem. When I saw that your IFR table matched the FIC values, I didn't give that another thought.

 

I have been saying that since the beginning that you had something off. You had to adjust to many tables compared to normal cammed cars I tune.
I never looked through your whole tune but 99% of the time you can just look at VE, idle, and timing and tell if what kind of tune it is. If those 3 are off then no need to keep looking generally.

 

Okay, well it didn't start on two tries. I didn't keep trying, because then it wouldn't be a "cold start condition."

I still have my startup airflow tables modified. Is it possible those are allowing too much airflow, and I'm running lean? I think I'll return those to stock. I mean, if injector data is correct, it should actually light off on an otherwise stock tune?

 

Well, with the stock startup airflow and afterstart enrichment/fueling tables, and the VE and IFR multiplied by 1.15, it was back to the endless cranking.

I tried with the stock startup fueling and the settings Ed had given me for the startup airflow tables. That didn't work either.

Is it possible that just sometimes, you need a little more afterstart enrichment with the combo for it to work?

 

It is a somewhat old thread, but:
Did you ever figure this one out Jake?
I have been dealing with this cold start issue for a while.
No problem on warm or hot starts.

 

Hose from the Racetronix pump to the hat was bleeding down pressure when the car was off. Only noticed it once I got a fuel pressure gauge hooked up.

I went back to stock parameters for almost everything. It never had issues once I got a new fuel hose on there.

 

Thanks for taking your time to answer my question. It definitely is a possible cause. I will check my fuel pressure at startup to see what is going on.
RG