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Discussion Starter · #1 ·
Alright guys help me out here im getting anywhere from 1-5 knocks when I shift from 3rd to 4th, and 4th to 5th at redline. I just installed my Utec and im boosting about 16.5 peak psi. I'm running the stage2New map since im only running piss water 91 octane, i have no other mods except for the intake silencer removal. What should i do to fix this problem should i retard timing and/or advance my fuel, and by how much. However sometimes when i get the knock the Dashboard afr reads RICH. So i dont exactly understand what it is, could it really be the 91 octane. Thanks
 

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Yeah you should be running the stage 1 map.
 

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Discussion Starter · #4 ·
yeah i know i should be running the stage 1 map, but when i called turboXS about my boosting, and the type of octane im running they told me that the stage2New map runs better than stage 1 if im using 91 octane. I was just going by what the techs told me would be best.
 

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"However sometimes when i get the knock the Dashboard afr reads RICH. So i dont exactly understand what it is, could it really be the 91 octane."

I would first like to say that everything I am about to say is just my opinion, so take it with a grain of salt:). While you are pushing your car, the a/f ratio in the log should always read "rich". If it reads numbers while you are pushing your car, it could mean that you are running lean(that is probably not the problem though)... Just as some general rules, the lower the octane, the higher the chances are that the car will knock under harsh circumstanses. By retarding the timing, and or adding fuel, you can effectively make the car less agressive which should help with the knocks. While doing this, it is optimal to always monitor your exhaust gas temp to make sure it isn't getting to hot(cause that means the engine is getting hot).

On the note of shift knock, there are many many reasons you are expericncing it(in my opinion). Like the other guy said, if you don't have exhaust mods, you probably shouldn't be running a stage 2 map. Also, there are modifications which I think need to be made to the base maps to stop them from making a car knock after or between shifts.

If you notice when you shift, you probably take your foot off the gas..... Now this might seem insignificant, but it makes the utec change back to the 0% load column for timing and fuel values to use.... When pushing your car, under the stresses of boost, high rpms, and high load gears, having the timing and fuel change really dramatically, really quickly can cause enough stress to create knocks. If you look in the log, you can probably see where the timing jumps from the map, then to ecu, ad back to map. If the timing value jumps a bunch of degrees (from say 20 to 26 then back to 20) in a short amount of time or rpm, it can cause a knock. This is what I think is happening.

There are a few things needed to be done to fix this problem.... One would be filling in the 10-60% columns with some timing values other then ecu. The second thing would be changing the timing values in the 0% load column between 4000 and 9000 rpm to numbers instead of ecu. This will stop the ecu from advancing the timing so much between gears when it thinks there is no load on the engine(even though there is). On another not, like I said b4, this is all just my opinion, and I am no expert. Changine the timing and fuel maps can really screw up your car, so be careful if you are thinkin about doing anything I have said... Sorry for this post bein so long.

If you are planning on changing the 0% column in the timing map between 4000 and 9000rpm, here is how I do it. I take the average number from the timing values on the row after the 0%value I'm filling in, and that is the value. This makes it so the timing stays steady while shifting.. example

rpm-----0--10---20---50--80---100
4000 19 18 18 17 17 16
4250 20 20 20 19 18 17
4500 20 21 21 20 20 19

as a note though, if there are ecu values in the 10-60% columns, the timing will still jump.

peace
 

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Also try adding a unit of fuel from 6000-up in the 0% column. An atmospheric BOV also does this which is why some people reported better luck with shift knock after adding one. Basically it adds fuel when you lift to conbat detonation due to the ECU adding tons of timing at that particular point.
 

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Discussion Starter · #8 ·
Yeah i assumed that the BOV would help in between shifts so i put my HKS SSQV back in on wednesday, but to no avail it still gives me the knock between 3-4, 4-5 redline shifting. Im gonna probably edit my maps to tomorrow to see if that fixes it. Oh and by the way as of this past friday i got my Gruppe-S uppipe, HKS downpipe, and my Tanabe titanium exhaust installed, so im fully catless now.
 
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