Knock sensor going of its head

General Tuning Questions And Discussions
immortality
Posts: 3416
Joined: Thu Apr 09, 2009 12:31 pm
cars: VH, VN, VS, VX

Re: Knock sensor going of its head

Post by immortality »

When/where is the knock occurring? You can try running it a little richer (around the 11:1), Try a little more AE if the knock is occurring on throttle application.

Other things to consider is improving the Cold Air Intake as that will directly effect knock as well as exhaust system, any back pressure will result in cylinder charge contamination/dilution which will also add to knock.

On our L67 the factory twin into single exhaust was causing knock issues with an 8psi pulley fitted at higher RPM's, improving the CAI helped and also a sick injector was contributing to knock. Also consider the plugs, a heat range colder may well help considering the high IAT's.

Do you still have the factory engine cover fitted? IF so, get rid of it as it's just another heat insulator. I also wrapped and insulated the fuel lines/rails, mine got hot enough to burn your hands and that can't be good for the fuel and cylinder charge temp either.

The one thing we don't have on our cars is bonnet vents and it's something they really require to bleed off engine bay heat, unfortunately I have yet to find a bonnet vent that looks good on a stock Commodore bonnet.
vp304
Posts: 451
Joined: Wed May 19, 2010 2:21 pm

Re: Knock sensor going of its head

Post by vp304 »

Immortality thanks for the tips
No engine cover
I know exhaust isn't the greatest.
Cold air I may make it better with a hole under the air box / guard style one picking up cold air from behind the bumper.
vp304
Posts: 451
Joined: Wed May 19, 2010 2:21 pm

Re: Knock sensor going of its head

Post by vp304 »

Pulled a few more deg of timing tonight in the areas that were knocking
Was cold outside so probably helped a bit also as iats were down a bit lower done a fair few pulls and knock sensor only knocked when i done 2 back to back full throttle runs. So some more slight work i am getting there.
thanks for the help guys
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j_ds_au
Posts: 384
Joined: Sun Jan 25, 2015 4:21 pm
Location: Sydney

Re: Knock sensor going of its head

Post by j_ds_au »

vp304 wrote: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
Why not? With its higher energy content, 95 is not much more "buck for the bang" than 91.

If that's the recommended fuel, then that's the price you pay for the performance.

Joe.
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