The answer isn't so simple. As ludikraut said, it's going to depend on your application. For a quarter mile run, you might get away with a few knock events and not really put the engine in real danger. Of course the knock is going to get more frequent, the longer/harder you run the car. For road racing people are probably going to tell you not to allow _any_ knock when tuning as this will only get multiplied after dozens of laps.

d

 

I should've read more carefully. I guess the answer depends on your application. I just hate pulling so much timing to get rid of the knock when I'm already running a low AFR.

 

I have noticed that a knock will be within acceptable range going WOT or doing a 3rd gear pull after running on the freeway getting good airflow. But if I do a 3rd gear pull after driving in stop and go traffic, engine noise will be higher and there will be a few high knock hits. Would running a lower temp thermostat help remedy/lower or prevent knock by keeping cyl temps a bit lower?

 

Ok, I finally got some time to look at my old maps. Nothing too glaring really jumps out, but I noticed a couple of things:

1.) your initial knock event seems to happen at the same place where your timing goes up to -1.4 again (6300rpm). That column looks like it should be -1.6, dunno why you have it going -1.6, -1.4, -1.6... For reference purposes, my old stage1+ V2 map was at -1.7 at that point (6300 and up) - although that was for 93 Octane, not 91.

2.) When I look at the old V2 stage 1 91 Octane map, the boost map dips at 5500 rpms (looks like: 93.3, 91.4, 94.9, 96.9...). If it's not like that already, then you may want to mimick that in your map setup. Seems to me like that might be just enough to keep your turbo from overboosting on 91 craptane in the upper rpms.

I'd probably go the route of pulling out some boost (in small increments across the board) and formatting your boost map to mimick item 2 above and fix the timing map per item 1.

l8r)

 

Ok, here we go again.

Mods are now: 2.75" DP, 3" HFC, Espelir 3" exhaust, greddy type-rs bov and AEM intake.

I loaded the stage 1 v360 map, then started tuning. after 8 street runs of adding fuel, pulling timing, and pulling boost, this is what i'm left with.

I will be getting a good boost gauge this week, but i've been trying to tune using the POS mitsu one. On this run it was just below 1.5 on the mitsu gauge, trailing off to 1.3 or so in the upper RPM range. What do you guys do with your boost map? do you keep it sloping up to keep the boost from falling off on top end?

What Now!?! do i possibly need to pull more timing??

Oh, and the large knock at the very end is when i lifted the throttle i believe. normal?

 

I didn't think you could. It was my understanding that it's a mechanical property of the stock turbo.

d

 

IIRC, the boost map controls the wastegate solenoid, which in turn controls how much boost is allowed to bleed from the system, so-to-speak. Or, to be more precise, how much help the wastegate spring gets. That's why if you put in all zeroes for the boost map, you still end up with some boost (basically however much the WG spring can hold by itself), and adding % in the boost map will raise that boost level until you reach the maximum amount of boost (100%) that the stock spring + solenoid can hold (23-25psi depending on atmospheric conditions).

For most stock turbo applications that I've seen you'll want to start out low(er) and end up somewhere between 95-100%. If you were to set the boost map to fall again in the upper rpms, then the boost would fall off more quickly. I run a stiffer WG spring (1.4 bar, I think) on my AMS kit, which results in 18psi of boost when I zero out the boost map.

Sackett, does your car get the same knock events when you put in higher octane gas? (read: got any 100oct gas available near you?)

l8r)

 

I have been datalogging with smart turned off, this weekend I turned on smart timing.(i'm a slow learner)
Looks like i have to do a better job of interpolating my timing offset after 6k rpm. but it looks like SMART works when it needs to.

Also it looks like the -2.2 smart timing offset got maxed out at the knock event that ocurred 7.3k rpm. This may well be happening to some of you guys as well. Does the range need to be increased?

 

Havent tried yet, as i've been trying to get this thing tuned on 91. I can put some in and see. I want to see if i can get some input on this from shiv too before i try anything else.

As for the boost map, I just installed the passive emulator thingy in my boost line, so my boost map has a range of like 74-88% right now.

 

Don't be afraid to yank out another 0.5-1 deg of timing above 6000rpm. 05s run very aggressive ignition curves. That coupled with 91oct and other VE-bumping mods can result in some audible high-rpm knock events. Back off a degree and see if the problem goes away. If not, dump in some 100oct as suggested, and see if it goes away. If it's STILL there, what you are hearing is normal engine noise.

Shiv