stumbles on cold start

[K Rob]

Would not start or idle without using the pedal

[SiriusC1024]

Man what the hell. If this doesn't show improvement I don't know what else to do.

- Cranking VE
- VE
- Fuel>Open Loop/Base STFT Open Loop Enabled

[K Rob]

Gm and let’s hope so !!!!

[reubone]

Start up try.hpt
Give that a try and see what it does. I'm curious for a better, same or worse

[SiriusC1024]

Start up try.hpt
Give that a try and see what it does. I'm curious for a better, same or worse

MAF is disabled for this SD portion. You're going for a MAF tune with this. Maybe you directed the changes to OP's first tune, but MAF fail is still 0hz, so the MAF settings won't work until that's changed back.

Cranking VE maybe, but I doubt it. Car is rich already.

I like your idea on min fuel in the Transient tab.

[horsepowerguru427]

If its running rich (im just coming in on the last page of this) why not try lowering the BRAF? its pretty high and for a cam that size id think itd be less since the VE table is so low at idle. i know its significantly higher than my BRAF on my cammed 5.3 thats 60-65% efficient in that area vs your 30%...Maybe my thought process is wrong here but lowering BRAF back down would cause less fueling due to less air, same effect as lowering % in VE table.

IAC steps start out pretty high as well...

Also, in transient fueling, it looks like fuel to wall impact factor has been lowered and i wouldve expected it to be raised in areas to account for the larger injectors. boiling time hasnt been touched and that should be raised in the low map areas to compensate for lower VE and ability to evaporate the leftover fuel.

Nothing has been done with injection timing either. On a cam that size the EOIT should be pushed back farther until the exhaust valve is closed or closer to it because of the excessive overlap. this Helps with not losing raw fuel out the exhaust but again changes transients because its spraying on an open intake valve, so you lose the cooling effect of spraying the back of a hot, closed, intake valve, thus the fuel doesnt atomize as well and again you get more transient fuel puddles.

Is injector data correct?

Just some suggestions....

Heres an EOIT chart to illustrate what im talking about with injector timing. Also Spray pattern and angle has alot to do with transients when you go from one to another.

[K Rob]

Update log - could there be a mechanical issue causing this ?

[K Rob]

If its running rich (im just coming in on the last page of this) why not try lowering the BRAF? its pretty high and for a cam that size id think itd be less since the VE table is so low at idle. i know its significantly higher than my BRAF on my cammed 5.3 thats 60-65% efficient in that area vs your 30%...Maybe my thought process is wrong here but lowering BRAF back down would cause less fueling due to less air, same effect as lowering % in VE table.

IAC steps start out pretty high as well...

Also, in transient fueling, it looks like fuel to wall impact factor has been lowered and i wouldve expected it to be raised in areas to account for the larger injectors. boiling time hasnt been touched and that should be raised in the low map areas to compensate for lower VE and ability to evaporate the leftover fuel.

Nothing has been done with injection timing either. On a cam that size the EOIT should be pushed back farther until the exhaust valve is closed or closer to it because of the excessive overlap. this Helps with not losing raw fuel out the exhaust but again changes transients because its spraying on an open intake valve, so you lose the cooling effect of spraying the back of a hot, closed, intake valve, thus the fuel doesnt atomize as well and again you get more transient fuel puddles.

Is injector data correct?

Just some suggestions....

Heres an EOIT chart to illustrate what im talking about with injector timing. Also Spray pattern and angle has alot to do with transients when you go from one to another.

Thank You for your suggestions !!!!

[horsepowerguru427]

your power enrichment was set to be on all the time. i fixed that and also disabled DFCO which you had enabled all the time as well. i adjusted transients and eoit a little as well. The PE alone was putting you at .8 lambda plus OL fuel table is pretty close to what EQ ratio it was commanding in the log. try this tune file and see if it helps any....If it was mine id wanna start fresh so i knew what all was changed, but thats me.

[K Rob]

I opened up the throttle blade just a bit and reset the tps - its blowing raw fuel out the exhaust as it has been - Thank You all !!!

[K Rob]

your power enrichment was set to be on all the time. i fixed that and also disabled DFCO which you had enabled all the time as well. i adjusted transients and eoit a little as well. The PE alone was putting you at .8 lambda plus OL fuel table is pretty close to what EQ ratio it was commanding in the log. try this tune file and see if it helps any....If it was mine id wanna start fresh so i knew what all was changed, but thats me.

Okay it fired right up - high on idle speed - I took 1 turn out to bring down idle some

[reubone]

Excellent catch. I didn't even look there as the ve was only set to disable after 3500 rom previously so I figured it was enabled. My bad

[reubone]

Start up try again2.hpt
Hopefully between all of us we will get there

[K Rob]

okay - i opened it up 1/2 turn to get it to start and closed it 1/4 after startup

[reubone]

Start up try again3.hpt

[K Rob]

No start

[SiriusC1024]

Wait lol. The PE was on the whole time? No wonder. Thx horsepowerguru427.

K Rob which revision are you using? Like are we trying to do SD, or did you switch it back to MAF tuning? From now on it'd be helpful to post the tune you used along with the log. It's hard to keep track of all the revisions otherwise. VE12 looked a lot better, but what changed? Was it PE settngs or enabling MAF or...?

[K Rob]

Startuptryagain.hot goes with ve12

[SiriusC1024]

Ok then it's still in SD mode. MAF fail is still 0hz.

Is the fuel system factory? It seems like maybe high pressure.

Lowering VE is showing improvement, but it's getting down into pretty low numbers to make it work right.

[K Rob]

Stock short block LS1
TEA light ported Trick
Flow 220s
64cc chamber (10.5:1)
BTR stage IV cam
233/248 .630/.615
111.5+2.5
92mm intake and throttle body
E85 42Ib iniectors and
Racetronix 255 pump, with hotwire kit.
Kooks 1 7/8 headers 3 inch collectors. 3 inch y pipe to 4 inch Mufflex exhaust Magnaflow muffler.
Th400 reverse manual valve body. With trans brake.