boosted g8 at 5psi, can't tune out knock.
08-30-2009, 06:37 PM
#21
9 Second Club
08-30-2009, 06:41 PM
#22
it does not look like false knock. i wish it was on my laptop and i would just post up a pic. an uneven sawtooth all the way threw 3rd and half of 2nd. jump tp 4deg fall to 1, jump to 3deg fall to 2, jump to 5deg fall to 3, jump...
that is at 11.5deg at 4800 and 15deg at 6000rpm.
then with 10deg it is completely clean.
doesn't that seem real?
that is at 11.5deg at 4800 and 15deg at 6000rpm.
then with 10deg it is completely clean.
doesn't that seem real?
08-30-2009, 08:03 PM
#23
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I think I posted this just after your post....never mind.....
Did you 0 the afr vrs spark? Is 11.5 commanded or what your logging?
Same goes for the 10 degree, thats commanded, but is that what its getting?
The iat corection is zero
the ect is zeroed?
I m not to up on the new pcm though...Im just guessing.
Did you 0 the afr vrs spark? Is 11.5 commanded or what your logging?
Same goes for the 10 degree, thats commanded, but is that what its getting?
The iat corection is zero
the ect is zeroed?
I m not to up on the new pcm though...Im just guessing.
09-04-2009, 07:11 AM
#24
i am 99% sure the knock we were seeing was real. i added a meth kit and it all cleared up. before at 5psi we got a little knock retard. at 7psi it was all over the place.
now with 10psi and the meth i see no knock at all. you guys that can go higher might just have better fuel available.
now with 10psi and the meth i see no knock at all. you guys that can go higher might just have better fuel available.
09-04-2009, 09:56 AM
#25
TECH Addict
my friend has a supercharged bonneville and it runs only either 6 or 8 degrees of timing when in boost (i forget which) and if you budge it from there it is KR city. They owners of these cars found it was due to the super restrictive exhaust. when they open it up they can run more timing / add power. like the other poster suggested I would try opening up the exhaust and seeing what happens. thats a free test at least.
09-04-2009, 01:29 PM
#26
9 Second Club
i am 99% sure the knock we were seeing was real. i added a meth kit and it all cleared up. before at 5psi we got a little knock retard. at 7psi it was all over the place.
now with 10psi and the meth i see no knock at all. you guys that can go higher might just have better fuel available.
now with 10psi and the meth i see no knock at all. you guys that can go higher might just have better fuel available.
09-04-2009, 04:00 PM
#28
Listen and stop guessing. The human ear is far more sensitive and a better filter than any knock sensor Ive seen. When listening with "det cans", its easy to pick up even the slightest hint of knock. Ive tried this in combination with a knock sensor based/electronic only device, and I picked it up when the knock sensor remained silent.
11-16-2009, 04:17 PM
#31
pretty fast, 11.44@124.5 with a lowly 1.92 60'
that was before the cold. it feels much quicker now.
i am working on some exhaust right now. duel 3" with just one pair of magnaflow mufflers. should help out. i will report back on how that goes.
that was before the cold. it feels much quicker now.
i am working on some exhaust right now. duel 3" with just one pair of magnaflow mufflers. should help out. i will report back on how that goes.
11-16-2009, 06:05 PM
#33
11-16-2009, 08:05 PM
#36
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I'd say you will find your answer with race gas. Not all knock is audible to the human ear.
Have you compared the G8 knock sensor sensitivities to other Gen IV engines? I battled with false knock for a long time and then found out GM set the knock sensor sensitivity super high stock. Check out a 4.8/5.3 tune and then a 6.0 tune.
Have you compared the G8 knock sensor sensitivities to other Gen IV engines? I battled with false knock for a long time and then found out GM set the knock sensor sensitivity super high stock. Check out a 4.8/5.3 tune and then a 6.0 tune.
