Desired Airflow {B4307}

[minytrker]

I havent had time to mess with it yet but I have noticed it surges alot less when its cool outside vs hot.

[Darkness]

I havent had time to mess with it yet but I have noticed it surges alot less when its cool outside vs hot.

Must be CL vs OL then.

[minytrker]

Must be CL vs OL then.

No its in CL when it does it. It surges when the temps are around 100 outside, at night when its maybe in the 80s it surges less.

[VYSSLS1]

the most common cause of surging is fuel, timing would have to be fluctuating near 20 degrees to cause a major surge.

if its in closed loope, when u have the problem, look at short & long term fuel trims.

or send log file, and ill have a look.

[SSpdDmon]

the most common cause of surging is fuel, timing would have to be fluctuating near 20 degrees to cause a major surge.

if its in closed loope, when u have the problem, look at short & long term fuel trims.

or send log file, and ill have a look.

Not true. When tuning an A4 LS1 w/ 232/234 595/598 112 cam, the timing was the surge culprit and it wasn't jumping more than +/- 5 degrees while the torque converter was locked. At 1600 rpms in 4th gear, it felt like your neck was going to snap in half. I set the timing to a single number from ~2000 rpm to ~1200rpm and 90% of the surging went away. Fueling was in closed loop maintaining a stoich AFR with the NBO2 sensors.

[VYSSLS1]

Not true. When tuning an A4 LS1 w/ 232/234 595/598 112 cam, the timing was the surge culprit and it wasn't jumping more than +/- 5 degrees while the torque converter was locked. At 1600 rpms in 4th gear, it felt like your neck was going to snap in half. I set the timing to a single number from ~2000 rpm to ~1200rpm and 90% of the surging went away. Fueling was in closed loop maintaining a stoich AFR with the NBO2 sensors.

Im sorry read your post above where even u state its either fuel or timing, obviously your car isnt running enough timing at that rpm/load for this cam, to cause a major surge at cruise with only 5 degrees timing variation. and u can still have a air/fuel ratio of stoich, but what about your fuel trims, if your ve table is out and trying to go to closed loope this can result in a sure as well.

Im sorry you are the expert, running a 12.5 with a huge cam, etc.

and i dont own a Blown forged ls1 with a cam as well running 16psi. and running on 12 on the street to stop the power sliding when accelerating over 100km/h.

But anyway back on with the thread.........

[VYSSLS1]

No its in CL when it does it. It surges when the temps are around 100 outside, at night when its maybe in the 80s it surges less.

any new logs on this.

[SSpdDmon]

Im sorry read your post above where even u state its either fuel or timing, obviously your car isnt running enough timing at that rpm/load for this cam, to cause a major surge at cruise with only 5 degrees timing variation. and u can still have a air/fuel ratio of stoich, but what about your fuel trims, if your ve table is out and trying to go to closed loope this can result in a sure as well.

Im sorry you are the expert, running a 12.5 with a huge cam, etc.

and i dont own a Blown forged ls1 with a cam as well running 16psi. and running on 12 on the street to stop the power sliding when accelerating over 100km/h.

But anyway back on with the thread.........

I was merely commenting on the bolded part of your response. I never claimed to be some kind of expert....only to have experience that contradicts your exaggerated statement. In my experience, timing is what cured both of my friends' surging issue (yes they both are running that cam). Fueling was already in line since the cars were in closed loop with minimally negative fuel trims. My car may not be forged and blown like your almighty wonder. But it did manage to rip off a 12.5 on stock internals with a little room for improvement thank you very much. Try not to assume too much. It makes you look like even more of an ass with your 9 posts.

FYI - those cammed cars were running 38*~40* timing (stock) at the conditions I mentioned in closed loop with -1~-3 LTFT's. What I was trying to explain was the surging was coming from the timing jumping in and out of different cells. More timing (43*) helped along with the fact that changing the surrounding cells to be the same number (43*) is what eliminated 90% of their surging. Their timing wasn't jumping between 20* and 40* like your statement claims is a requirement for timing to be the culprit for such massive surging.

[joecar]

I'm watching... so everyone keep it civil...

[SSpdDmon]

I'm watching... so everyone keep it civil...

Sorry Joe...his response was just a bit uncalled for. BTW, can I change my title from Lifetime Member to Self-proclaimed Resident Expert of Cammed LS1's?