Dylanplace

Mine is a dog in this big truck. I'm in southern maine

truckdoug

iTrader: (26)

you got a cam/converter/gears?

Dylanplace

This one is Stock 4.8. 80e 410

truckdoug

iTrader: (26)

ok cool. hey I was looking at your log data for the advance vs kPa and it seems kinda high to me




15 degrees at 4000 rpm and 8psi is on the edge from what I gather.

I'd take it back to the 12 degrees you have in it at just before that area and work up.

I like that you keep timing in it until a couple psi builds. I do this too, but you gotta pull it smoothly.

you're on the right track bro.pull that timing back down to maybe even 10* with the stock cam and keep reading the plugs

sbcgenII

iTrader: (1)

It would be if you were to rich already. Which you are. The only reason to shoot for 10 afrs would be on the first drive to see where you are at and make sure it's not lean. Got any plug pictures?

newschool72

iTrader: (12)

That was my point. If he is in the 10s already and the sensor reads lean, then it could be PIG rich, ie rich enough to do damage. he said its tight though, so all I can do is take his word on that one.

sbcgenII

iTrader: (1)

Just looked at your log and tune. Your Boost PE is set at 11.3 but I am seeing 10-13 AFR underboost on your wideband though.

Dylanplace

ya I couldn't get it to command properly that was another issue so I was slowly fooling it through the ve to try to get it close.

SethU

I don't have or use HPTuners, so didn't pay much attention before and missed this little detail.

The file name is a little telling. If it's that rich and knocking, there's typically too much ignition advance.

Dougs post above is good advice. I might even pull more and slowly sneak up on 12ish in that 4k area, smoothly ramping it to about 14º at 6k, while also sneaking the fueling into the low to mid 11's. Little by little.

This assumes the commanded timing is the actual timing. If it hasn't been verified and any offset accounted for, these numbers could be problematic too... if 12º commanded is actually 18º, or whatever.

Dylanplace

I named it that because that's when it broke the ring lands and started ticking

JoeNova

If it broke that many at once, that's a tell-tale sign that its a generalized problem like a tune. What wideband are you using?

SethU

Ah. Got it. Yeah, I imagine it would make a little noise after that. LOL

Can you post a pic of the face of the pistons

dburt86

iTrader: (2)

Your torching those pistons. Check your fuel setup. Running 1 wideband just means its an average of all the cylinders so there could be cylinders that arent being fuelled as much as the others.

Do a pull and yank all the plugs and compare them. If they look different, then you have issues.

sbcgenII

iTrader: (1)

Are your tuning in open loop? Steady fuel pressure?

Dylanplace

Yes. Fuel pressure is 58 to 60. Using an aem wideband

Dylanplace

this engine had an ls9 cam aswell

dburt86

iTrader: (2)

Thats not just a few degrees too much timing, thats something way fucked. A broken ringland, ok, too much timing at pk tq.

But those pistons are torched.

Unless ur keeping the thing floored for minutes, id say you have something else going on.

Dylanplace

well what are you thinking then. It looks to me like there is enough fuel from the black

stevieturbo

mmmm nope.

dburt86

iTrader: (2)

I would say fuel starvation or your timing isnt what you think it is.