Knock sensor going of its head

[vp304]

Thanks to you guys my vr with l67 swap is running great
Starts runs drives good hot cold. Have wideband set the mixtures and got them pretty good 14.7 on cruise and down to 11.5 to 12 afr on boost
Just one thing i cant get my head around is this knock sensor going off like crazy as soon as i go over say 35% throttle or so and put the car under any load.
At cruise it is no worries.
Have turned of knock sensor and tested 2 times and it rattles its head of so is genuine knock.
Checked plugs and is signs of knock.
Have taken timing outa boost map still knocks ?

Run down on car
l67 standard boost pulley
Vr knock sensor running vr ecu on 11p
180 thermostat
ported blower
Vs cold air intake
Shorty extractors single 2.5 inch exhaust
map sensor of lower intake manifold same as IAT sensor is mounted in lower intake manifold
runs on 91 fuel as daily driver work horse. (yes i know 98 would be good but not happening)

Do these l67s, not being intercooled with the crazy high 80c or so intake air temps im seeing, mean i have to pull even more timing out than what i have below?
As can be seen by the screen shots one point its not even on boost and knock sensor is going of ?
and the other screen shot is like maybe 3 psi of boost and under 50% throttle and knock city ?

[vlad01]

From what I heard/seen stock L67 and ecotec are pretty knock limited so I'm not that surprised really. I have only even tuned ecotecs that were modified and on race fuel or E85 so knock wasn't a problem but one thing for sure is they don't like much timing compared to the older Buick engines, 18-24º at 100Kpa iirc, even with bigger cams, I think stock is like 16-18º?


Meanwhile my older engines are running up around 27-29º. I recently did a boosted one and at about 160Kpa it's 24º but it is intercooled, doesn't have any audible knock but the owner is going to get that looked at when on the dyno to make sure it's good.

[vlad01]

I just noticed your wideband is reading 20 AFR, even the O2 sensor is reading lean in the 1st pic.

[vp304]

Thanks for the info vlad
that gauge does not do anything or move at all for wideband in tuner pro
Wideband im using is a innovate and just use the separate display that comes with the innovate. It is not wired into the delco at all.
Factory o2 sensor when i run in closed loop looks like its doing what it should be and i dont have any engine codes or trans faults in tuner pro so must all be working ok.

[immortality]

The L67 came from the factory tuned on 95ron fuel, running on 91 isn't recommended. These engines don't need a lot of timing to begin with and as you can see they run fairly hot IAT's. 91ron fuel on this combo is a recipe for disaster.

[vp304]

Oh thought they were a 91 fuel engine.
Just see a lot of old timers driving L67 statesman's and Calais etc around towing trailers caravans. Couldn't imagine them running them on 95 all the time

[immortality]

The ecotec is happy on 91, when you start adding boost you quickly become knock limited as you have discovered.

[vp304]

Geez really gotta pull some timing. I may try get onto mates dyno and finish of tune there.
Thanks for the info

[VX L67 Getrag]

If your hearing detonation & know it's trying to pull timing even with knock sensors disabled I wouldn't go anywhere near a dyno!

Re-Enable knock sensors & start pulling timing until you stop hearing detonation for a start!

[vp304]

I only turned knock sensor of and done 2 50 per throttle stabs and then turned them back on. They have been on from the start