Page 2 of 3 FirstFirst 123 LastLast
Results 21 to 40 of 42

Thread: Knock Resistance

  1. #21
    Advanced Tuner
    Join Date
    Jan 2015
    Posts
    563
    Quote Originally Posted by Seishuku View Post
    Attachment 125978

    Log file here:
    https://forum.hptuners.com/attachmen...9&d=1668289385

    This is on completely stock engine, the only thing I currently have is a single 3" catback and aftermarket blow-off valve.
    Wow MCT of only 38* is impressive. Gotta be the difference. Your at a much higher load and timing with less knock. Unless your running race gas or ethanol I don't have an explanation for that. I hope I don't just have a knock prone engine.

  2. #22
    Advanced Tuner
    Join Date
    Jun 2019
    Location
    Wisconsin
    Posts
    293
    Oh, I guess it's not just the exhaust and blowoff valve, I have an intercooler too, but I'm sure I've mentioned that before in another thread.
    Yeah, winter here means turbo weather lol
    But this is just on 93 octane pump gas (93 (RON+MON)/2), though I've also ran 91 before and didn't see any difference in knock readings.

    I guess it's possible your engine might have some flaw that could cause it under load, but seems unlikely since you're basically running stock load in that log.

    Something else you might try, clear you keep alive memory (KAM), that will reset all learned adaptations, then give it time to readapt and get the octane adjust back up and see where things settle at.

  3. #23
    Advanced Tuner
    Join Date
    Jan 2015
    Posts
    563
    Quote Originally Posted by SiriusC1024 View Post
    Throttle Angle Source is TQ Red. < Driver Demand. There is a limiter happening, but can't tell what that may be. Probably something to do with torque vs air load. Could be cylinder pressure, which popped up briefly in Spark Source right before the timing drops in the first pull. The idea is that the throttle angle limit will be ignored by commanding WOT. Try it and see.
    fail.hpl

    No effect so far. Set start at 70 and max at 100. Factory was set at 200 so that should mean percentage is being used.

  4. #24
    Advanced Tuner
    Join Date
    Jan 2015
    Posts
    563
    Quote Originally Posted by Seishuku View Post
    Oh, I guess it's not just the exhaust and blowoff valve, I have an intercooler too, but I'm sure I've mentioned that before in another thread.
    Yeah, winter here means turbo weather lol
    But this is just on 93 octane pump gas (93 (RON+MON)/2), though I've also ran 91 before and didn't see any difference in knock readings.

    I guess it's possible your engine might have some flaw that could cause it under load, but seems unlikely since you're basically running stock load in that log.

    Something else you might try, clear you keep alive memory (KAM), that will reset all learned adaptations, then give it time to readapt and get the octane adjust back up and see where things settle at.
    I hope I dont have a flaw. Gonna start logging individual cylinders to see if I have a problem child. Also time for a service and changing spark plugs so maybe that will help? Also, next week should be intercooler time so I'll keep you guys posted.

  5. #25
    Advanced Tuner
    Join Date
    Jun 2019
    Location
    Wisconsin
    Posts
    293
    Quote Originally Posted by reubone View Post
    I hope I dont have a flaw. Gonna start logging individual cylinders to see if I have a problem child. Also time for a service and changing spark plugs so maybe that will help? Also, next week should be intercooler time so I'll keep you guys posted.
    Plugs certainly wouldn't hurt to do, I'm on stock plugs, but I have changed them within the last 1000 miles.
    I've been kind of wanting to try a step colder plug myself, see if it quiets up some of the knock activity I see and maybe let it add timing back in.

  6. #26
    Advanced Tuner
    Join Date
    Jan 2015
    Posts
    563
    Quote Originally Posted by Seishuku View Post
    Plugs certainly wouldn't hurt to do, I'm on stock plugs, but I have changed them within the last 1000 miles.
    I've been kind of wanting to try a step colder plug myself, see if it quiets up some of the knock activity I see and maybe let it add timing back in.
    You just keep rubbing it in don't ya hahahaha. All these stock parts and mad timing. Ill catch up you just wait! Ill let you know if it helps me at all.

  7. #27
    Advanced Tuner
    Join Date
    Jun 2019
    Location
    Wisconsin
    Posts
    293

    We'll get you sorted out eventually!

  8. #28
    Senior Tuner
    Join Date
    Mar 2022
    Location
    Indiana
    Posts
    2,783
    Tighten up the gap a bit since boost is higher. At least make sure they are on the small side of spec.

  9. #29
    Advanced Tuner
    Join Date
    Jan 2015
    Posts
    563
    Quote Originally Posted by SiriusC1024 View Post
    Tighten up the gap a bit since boost is higher. At least make sure they are on the small side of spec.
    I had planned on running .028 I believe. That what I would run on my SRT4 that worked pretty good.

  10. #30
    Advanced Tuner IARLLC's Avatar
    Join Date
    Aug 2016
    Posts
    942
    Yep. I gap plugs at .028" for EB rigs. Also just ordered the Ford Performance plug that is supposed to be 1 step cooler. Hopefully that upgraded intercooler will have your timing numbers improving. My huge intercooler sure helped my Expedition.

  11. #31
    Advanced Tuner
    Join Date
    Jan 2015
    Posts
    563
    Ok so I have noticed that cyl #3 seems to run less timing than the other three cylinders. It is often times the one lagging behind when tracking knock +/- per cylinder. It will often receive the least amount of advance and sometimes be in knock detection where as the other three are advancing. Ive heard that the balance shaft is driven close to cyl #3. Could this be why? Or could this elude to a cylinder defect of some sort? Screenshot (62).png
    Screenshot (61).png
    Screenshot (60).png
    Screenshot (59).png

  12. #32
    Advanced Tuner
    Join Date
    Jun 2019
    Location
    Wisconsin
    Posts
    293
    Could be balance shaft noise.
    On my engine, it tends to favor #3 and also #4, but those negative numbers aren't much to worry about, I try to keep it above -2, and get concerned when I see -4.

  13. #33
    Advanced Tuner
    Join Date
    Jan 2015
    Posts
    563
    Quote Originally Posted by Seishuku View Post
    Could be balance shaft noise.
    On my engine, it tends to favor #3 and also #4, but those negative numbers aren't much to worry about, I try to keep it above -2, and get concerned when I see -4.
    Ok, I'll keep that in mind. What about imperfections in the road? I have noticed that If I hit any bumps in the road during a pull it will register as knock. This seems overly sensitive to me.

  14. #34
    Advanced Tuner
    Join Date
    Jun 2019
    Location
    Wisconsin
    Posts
    293
    I suppose that's possible too, but the system does need to be fairly sensitive, since this is how dynamic timing on these engines work.

    To combat that some, you can up the recovery rate, so it bounces back faster from false knock.

  15. #35
    Advanced Tuner IARLLC's Avatar
    Join Date
    Aug 2016
    Posts
    942
    I might get trashed on here for admitting this but...
    Back in 2012 a friend of mine got a new Focus ST, intake, exhaust, and a COBB tune. Within 10,000 miles the balance shaft gears really came apart. To our amazement the rod and mains still looked OK and since the balance shafts were not immediately available he asked me to button it up without the shafts. People argued online about the affects but as far as we could tell it did not show any more vibration than before, revved much more quickly and seemed to gain about 20 HP.... He decided not to have me install new balance shafts.

    Maybe it would be worth the time to pull the balance shafts out (at least temporarily) to see if the #3 cylinder noise goes away.

  16. #36
    Advanced Tuner
    Join Date
    Jun 2019
    Location
    Wisconsin
    Posts
    293
    That's something I've been wanting to do, I just don't want to deal with dropping the subframe. lol

    I don't see the need for it either, all the 4 cylinder engines I've ever owned never had balance shafts, never any problem.

  17. #37
    Advanced Tuner
    Join Date
    Sep 2006
    Location
    Arizona
    Posts
    600
    Quote Originally Posted by reubone View Post
    Oh and ethanol is not an option around here unless I drum it in for myself. What about race gas or boosters? I know that ethanol period increases power out put so it would be the ideal fuel, I just dont have access.
    If you do use Octane Boosters, steer clear of the ones with MMT (which most off the shelf octane boosters and "race gas" concentrates will contain). It will not only foul your plugs, but will jack up you Wideband O2 as well with regular use. Torco does make a race gas concentrate that does NOT contain MMT and it's about the same price as the Lucas and VP boosters that contain the MMT).

  18. #38
    Advanced Tuner
    Join Date
    Jan 2015
    Posts
    563
    Quote Originally Posted by IARLLC View Post
    I might get trashed on here for admitting this but...
    Back in 2012 a friend of mine got a new Focus ST, intake, exhaust, and a COBB tune. Within 10,000 miles the balance shaft gears really came apart. To our amazement the rod and mains still looked OK and since the balance shafts were not immediately available he asked me to button it up without the shafts. People argued online about the affects but as far as we could tell it did not show any more vibration than before, revved much more quickly and seemed to gain about 20 HP.... He decided not to have me install new balance shafts.

    Maybe it would be worth the time to pull the balance shafts out (at least temporarily) to see if the #3 cylinder noise goes away.
    I may do this, Not sure yet but if I do Ill post on here about it.

  19. #39
    Advanced Tuner
    Join Date
    Jan 2015
    Posts
    563
    Quote Originally Posted by PSYKOSTEVO View Post
    If you do use Octane Boosters, steer clear of the ones with MMT (which most off the shelf octane boosters and "race gas" concentrates will contain). It will not only foul your plugs, but will jack up you Wideband O2 as well with regular use. Torco does make a race gas concentrate that does NOT contain MMT and it's about the same price as the Lucas and VP boosters that contain the MMT).
    Ill keep that in mind, Thank you

  20. #40
    Advanced Tuner
    Join Date
    Sep 2006
    Location
    Arizona
    Posts
    600
    Quote Originally Posted by reubone View Post
    A lot of you guys have figured out something that I haven't I reckon. I cannot seem to get anymore power out of this combo without running into knock reduced timing. The dyno says we have about 40ftlbs of torque improvement but only about 5-10 hp. Trying for anymore than this we get knock or charge temps over 125*. I plan to upgrade the intercooler here in a few weeks but what else have you guys done to increase knock resistance?
    Attachment 125947
    I might have been missing something at first, but I found it confusing reading the initial post and log since I didn't see any mention of what vehicle we were talking about. From reading other people's comments, I think I have figured out that this is a Ford Focus ST. Is that correct? Also, posting the log along with your current tune file is the BEST way to make sure that you get relevant answers to your question.

    Since I cannot see the current tune file to look up values you may be hitting in your limiters, etc here are my $0.02

    1. Your AFR commanded vs actual under WOT is off, and is running richer than commanded. Have you attempted to use the Speed Density Calculator yet to correct your VE across the Mapped Points? Rich AFRs in Direct Injection cars can create higher than desired cylinder pressure, which can lead to knock. Also, too many people ignore tuning the Speed Density values on Ecoboosts, which would be like Ignoring MAF tuning on an LS3. Yes, on the surface it appears more complicated than MAF frequency tuning, but HPTuners gave us this awesome scanner and awesome tools to be able to calculate the coefficients needed to properly adjust our VE Mapped Points.

    2. Under LSPI Reduction on the Torque Management tab, you may want to make sure that your limits are set high enough for the amount of boost you are trying to achieve. I know it says that it is the "Load Limit", so most people draw the conclusion that this is the Airload value they are referencing (where I see a max of around 2.20 Airload in your log), but from my observations over the years I believe this to actually be a Pressure Ratio limit (Manifold Absolute Pressure / Ambient Barometric Pressure), in which case I see you hitting values closer to 2.40 in your log. Then be sure your Combustion Max table and others related to that limiting are also in check.

    3. Looking at your Spark Source in the log around some of your higher KR events (-3.0 or worse in the first pull of the log) you are hitting your Cylinder Pressure Limit (See #1 about Speed Density tuning recommendation to get your WOT AFR closer to commanded)