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my knock went up to 74 today , howcome though ? this is wierd... like when i put my foot down (wheels spinning) then at about 4.5rpm i changed into 2nd gear... the knock is 74 . Why does this happen?

my knock went up to 74 today , howcome though ? this is wierd... like when i put my foot down (wheels spinning) then at about 4.5rpm i changed into 2nd gear... the knock is 74 . Why does this happen?

you get knock from more load on the motor on the same management settings, second gear is more load.

but there's many other reasons. Im not an expert tho

if you guys are noticing more knock then try and remember the type of fuel you put in your car last.

I always found that Caltex made my car knock like crazy and optimax / v-power was not much better but it was better. When i switched back to BP Ultimate 98 or Mobil Synergy 8000 it would go back to normal.

give this a try

yep i only use bp nowdays, after going through a few bad batches of caltex. if you had your car tuned and its knocking (not on limiter), take it back and get them to fix it, you payed for a tune, if its still knocking then they havent finished it yet.

fuel cut limiter does not create a lean and dangerous combustion, theres no combustion at all, due to there being no fuel. the ecu does not fire the injector at all when its cutting that cylinder. even if a little fuel made its way in there from a previous injection it would not be anywhere near enough to ignite. if the motor is actually knocking on limiter its from a cylinder thats firing normally, not one thats being cut. like i said before, if your worried about knock readings on limiter, take some timing out temporarily and see what happens.

  • 4 weeks later...

depends how lazy your tuner is, some tuners only bother to tune cells that are traced on the dyno, so when you're on the road those other cells are loaded and POW BAM.. knock...

I had to borrow a Datalogit and fix up my tune on my own after, and at 7200rpm, I pulled out 2degrees of timing, so on Load points 16 and 17, it's 13 and 12 respectively.. and I've set my rev limiter at 7300rpm.. at 6800 it's 15 degrees then at 7200rpm it's 13

rev bashing in 2nd I usually don't get knock more than 50.

BTW.. you can get Innovate LC-01 Kits with Blue Gauges on eBay for $250 delivered.. love the strong aussie dollar!

if you have your limiter set slightly higher than a ne point you can interpolation to only lower your timing on limiter. on a 25 7200 is ne18, if your limiters at 7300 then you can simply take a lot of timing out of ne19 and your timing wont drop until 7201rpm. wont make much difference but it'll make sure theres no knock on limiter without sacrificing power in the last 400rpm before it.

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