Ok i just wanted a take on the inconsistency of knock counts and where you guys draw the line, for example

you get your boost/fuel/timing set up. You go to log you pick up 1-2 counts of knock your happy, then you do another pull on the same strech of road same gear, and you suddenly get 10-12, so you go WTf? then you keep doing pulls and it just bounces around between 1 and 12 counts of knock, some pulls are almost knock free others are as high as 12 and through an rpm range of like 4-redline, other times you pick up 5 or 6 for between 5000 and 5500, and then knock free .
(its almost like wtf is your ecu just throwing dice randomly to generate your knock counts.)

So with all this inconsistency would you accept that? i mean some runs come out almost knock free and others knock up to 10 or 12, i dont know if this happens with everybody, but it happens to me i dont know if 91 octane has a role in this or what. but i wanted you guys to throw in your 2 cents and tell me if you would accept it that way or not, i mean we all want a knock free pull or as close to it as possible, while making the highest amount of power,

 

Well I would not accept 10- 12 counts and do not think you should be getting those extreme inconsistencies...What was the weather like in both cases (temperature & humidity)? What boost are you running? ECU controled boost or MBC? What did your AFRs and loads look like in both runs? My guess is that you are getting phantom knock -- do you have a 3" TBE? If so, make sure it is not touching or rubbing the oil pan / TC. I know that in my car, I had knock when the TBE was touching the oil pan....

Good luck

 

Inconsistency is all part of the tuning process..

You have to rule out things like your downpipe rattling or other noises being picked up as knock.

Typical knock on repeated passes would be roughly the same if its tuning related, this is a general point and not always the case. Sometimes "Hot Lapping" a car without giving it a chance to cool down will result in increased knock on subesquent passes, however, the correct way to tune is to detune the car slightly if that happens (Add fuel and/or reduce timing) and you can upgrade components (intercooler, etc).

There are three ways to tune, for drag racing, road racing, daily driving. For a tune for daily driving, you tune for the worst common denominator, which means you are conservative and want to keep knock counts as low as possible.

For Drag Racing, you tune for the best common denominator (optimum conditions) and accept that you may get knock on your runs, only you minimize it as much as possible, but the car only has to run for a short period of time so you can usually get away with pushing the limits of fuel/timing/boost as long as its monitored and knock is minimized.

For Road Racing, you tune conservatively, since you will be making sustained high load runs, which means you need to keep knock minimized at all costs, and coolant/exhaust temps as low as possible to prevent failure. Depending on the fuel used, the timing, fuel, and boost are kept to levels where risk of failure is lowest. The name of the game is producing consistent predictable power, with smooth delivery, under varying loads and throttle inputs.

For a street tune its somewhere in between, at high loads the tune is similar to a drag race tune, at part throttle, the tune is similar to a road race tune. Finally you run boost/timing appropriate to your fuel, and not just the fuel you currently have, but the worst fuel you may run into. Additionally drivability comes into play, where cruise and very low load part throttle driving adjustments are made to be smooth, and transitions are not as abrupt. (no light-switch tuning). Additionally Idle quality, proper injector scaling, proper MAF tweaks, etc are much more critical.

Of all the types of tunes, a proper street tune would take the longest to complete as its not about a few dyno runs at WOT, but it starts out as that, and then you fine-tune it for different driving conditions.

Everyone is different and their needs and driving style is different. Some people don't might lightswitch like delivery, while others want smooth and predictable delivery. Some want *****-out power, while others want day to day consistency..

But what it comes down to is, COMPROMISES, if you want a reliable car, it won't make the same power as someone tuned on the edge for drag racing, but the car should run better and feel better in daily driving.

A good street tune cannot be done in an hour, or through the mail, it takes time, and it requires someone familiar with your driving style and needs and should be done over several days and different weather conditions. This is why factory tuning R&D can take months, and typically gets revised a bit every year with a new model.

This is not to say that 1 hour dyno tunes or through the mail tunes are bad, its just that their a starting point for someone looking to make the best of what they have in front of them. But every car is different and tuning is different for every car. Fortunately, experienced tuners do take this into account and have refined their maps to the point where daily driving tune is improved, and the fine-tuning for WOT is what is focused on for your mods.

But your mileage may vary..

 

i get what you are saying for the different tuning styles,

its just that it gets a little frustrating with the inconsistency, the only thing i have is a DP, its not even close to the oil pan, i know its the tune because if i pull 1 degree through that range it comes out to 0 knock all the way through, 95% of the time. Now i have a wideband and my AFR seems to always be consistent, the only thing i can think of is, i use the stock BCS to control boost, i pulled out the restrictor pill runing to the BCS and dialed my boost in to 21 psi, and it holds it there 90% of the time, but every so often i will get a drop off to 16 and shoots right back up to 21 and holds, its weird cause it happens like an intermittent thing,

i think that might be my problem why im suddenly getting 12 or 1-2 counts with different pulls.

I'm going to go back and try to set my desired engine loads up better for it to be a smooth transition even if it does taper, because i think the immediate drop and increase of boost causes that.

 

O.K. sounds like you are on teh right track.

A few tips on tuning the boost setup. Take look at your logs from a run where the boost was cosistant. Now, map out the calculated load vs rpm as an example:
3000 220
3250 240
3500 255
3750 260
.
.
.
6500 220
6750 215
7000 210

now, you want to setup your boost desired load AND boost control load offset so that the additive product of the two equals your target load. For example

Boost control load offset = 140
boost desired load table:
3000 120 (target load = 120+140 or 260)
3500 120
4000 110 (target load = 110+140 or 250)
.
.
6500 70 (target load = 70+140 or 210)
7000 60 (target load = 60+140 or 200)

Next set your max wastegate duty cycle to something flat like 100 across the board and go do some logging. you can adjust the max wastegatge duty cyce up and down till you find the sweet spot where you are getting very close to the target load values, assuming you are being realistic about the target load values and not trying to hit 240 load at 7,000 rpm.

I think the problem you are having is due to not having the maps setup correctly and the error correction is kicking in on overboost and pulling the boost down, overcorrecting, then letting it run back up.

Also, If you are not able to run 21psi at redline, don't worry about it, let it tapper as much as you need to be consitent, then add a little more timing or run it a little leaner.

Hope that helps get you going.

 

thanks i got what you were saying, If you look at it as a load parabolic curve, and dial the desired engine load according, it comes out way smoother, i was able to get it to spike to 22 and hold it until about 6k and only after 6k it seemed like it dropped 1.5 psi by 7k rpms, in any case im happy with it, it feels like a nice smooth pull, its amazing what you can do by simply pulling out the restrictor pill to the BCS, i cant wait to get my timing and AFR set up tomorrow, so i can really feel it open up.

the only thing i noticed, since its like 40 Degrees here with like 99% humidity, on some pulls it still bounces around, i take it it might have something to do with outside temps, and things like that, with the ECU compensating or something. im going to try it when its a little warmer and less humid tomorrow, but in any case setting up boost by following desired engine load worked, the only thing is with evoscan's calculation your about 30% lower actual load then is calculated, oh well atleast its consistent.