fastcarfreak

yesterday night when i was out driving around, i decided to open her up. After opening her up i look at the power fc and my peak knock reading was 86. I tryed doing a search but was unsuccesful. Can anyone tell me if this is too high of a knock rating. I am running 94 octane by the way. anything i can do to fix the knocking or is 86 peak not a big deal?
Adam

rynberg

A peak knock number by itself is meaningless. It could have happened when you shifted, for example. Also, the readings people get (which are just noise levels in a certain frequency band) vary from car to car.

Have you been on dyno with a PROPERLY functioning wideband sensor to verify your A/F ratios?

What mods does your car have and is your PFC tuned at all?

Johnny

I heard 2-3 knocks recently...wont go to that gas station again ! it was 76 by the way...

PFC read 175 !!!

zooq

i read up to 220 sometimes its just noise from shifting. i think someone data logged the knock and found out that the high numbers last for only milli seconds during shifting

ZeroBanger

I used to regulary hit 125-200 on my old engine. at somepoint I guess the knock was real. On my new engine with my water injection off I never hit above 30 yet , with it on I usualy never hit above 12-17.

I had broken motormounts before, that may have been a reason why my #'s were so high.

I think you need to find out your average or typical #, and be cautious to anything abnormal.

SpiritR

Whats your mods?

86 isnt terrible anyway. Its worth it to look into though, doesnt hurt to look.

Your knock can go up from:
Poor spark plugs
All ignition parts IE coils and such
Oil needs changing
Or you might need a little tunning.

I WANTED TO ADD:

If you dont ever open it up or drive rarely and you open it up you may get a high knock reading till you blow all the crap out of your engine.

NorthwindHost

Oh man, I thought my 59 was really high and was a bit worried. I guess I can put my worries to rest.

Johnny

dude if you knock...it's unmistakable...I'll never forget that sound... I was like WTF....**** look at the PFC quick yo

fastcarfreak

the car has been tuned by dave at kdr, he accually tuned it to be a little bit rich do to my stock intercooler. As a matter of fact i had the car out tonight and hit 146 on my peak knock reading.

SleepR1

knock readings can vary so much between cars, and between conditions. I've stopped monitoring knock, since the reading is close to meaningless. I know with my car, I've had readings as high as 175 peaks at the track running Sunoco 94 octane, in 55 F ambient temp conditions. My Power FC map was also done by Dave Barninger of KDR based on my mods (see opentracking.com link). It tends to run on the rich side. There's a little retardation in the ignition to work with the streetport, and a few splits in the timing.