Just wondering if anyone else is seeing their tune showing a few knocks during the immediate spool up(2500rpm+) then on deceleration(which i heard was not as important) im not seeeing knocks more than 3...and im wondering if this is not something to be overly concerned about. I always run 93 oct. and thats what my flash was tuned for. Any help is appreciated.

 

seee if your pulling timing when the knocking is occuring...maybe your running too much timing or too much a/f ratio...or could just be phantom knock

 

I see a few counts of knock when I start at 2500RPM. Try the pull from 3500 and see if the knock still apears.

 

yea if i start a pull at like 2300 or so i somtimes get up to 3 counts which tapers off to 0 by like 4K but i blow it off because its during spool and alot of people have the same problem. My timing isnt bad during this or i would be more concerned

 

There is no reason to lug the motor from 2500 rpm .... in fact I think that is retarded. Start at 3k on a flat surface without building boost until you hammer it.

 

I usually log from 2k in 4th and do not see knock. I tune kind of on the safe side though.

 

i had it, and sometimes it would lead to reduced timing at peak VE. So i reduced timing at spool-up.

 

A few counts is normal during sudden load changes because the knock control system is differentiating the knock signal (looking at the rate of change). It should be short lived and 1 or 2 if of this variety.

Higher knock sums due to real knock are real performance killers because the ECU retards more timing and for longer than would have occurred if it was tuned to just avoid excessive knock sums.

I don't think there is anything wrong with lugging the motor from 2500, I have full boost at that point and it is a very easy drive to pass something.

 

it can be corrected by adjusting the fuel if it's too lean and timing if the fuel is correct

 

Retarded or not, most logged runs are usually done at this point upward. To each his own. Of course on the track or street no-one is going to go full throttle in 3rd at 2500rpm but it generates a different load on the engine for logging purposes. Im glad so to speak more of you guys are getting the same effects on spool up and i thank you guys for your input.

 

I do all my racing from 1500 to 3000 ... just kidding! The only reason you'd worry about the tune there is to keep knock in check so the ECU doesn't dump fuel or pull timing and throw the rest of the tune off when you're trying to dial it in.

 

The timing value should be between 1-3 anyway in those knock areas so adding some fuel should do the trick. I have afew 1 counts on spool up that I'm not to worried about compaired to my 5-6 counts that I had with my custom dynoflash tune.

 

Thanks for the info!

 

where area are you referring to? what load and rpm because that sounds awfully low for the area we're discussing.

 

i think he referred to peak load, where in fact we're talking about spool-up...