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Solo_S14 Needs Help!! - Tuning Experts??

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  • Solo_S14
    started a topic Solo_S14 Needs Help!! - Tuning Experts??

    Solo_S14 Needs Help!! - Tuning Experts??

    Hey guys,

    Old member of the forum, I'm sure some of you remember my huge build thread from 2009 - 2011 (Project NL S14): http://www.nissanroadracing.com/showthread.php?t=1451

    I'll bet that anyone who has followed the thread remembers the constant engine troubles that I've had. After losing a completely built engine at the end of '09, I installed and immediately melted a stock engine in the spring of 2010, then built the 3rd engine during the spring of 2010.

    To summarize the cars history since then, I've basically still been chasing the engine issues!

    When I lived on the East Coast (up until 2010), there was no dyno and no professional tuning in the province. Since then I have moved to the West Coast, found a dyno and a tuner, and logged some dyno time.

    I tried last spring, and again this spring, and both times the car has made consistent power (also consistent with the original motor in 2009), but I have had consistent and unexplained detonation above about 5750 RPM. Each time we tune great (safe) Torque and HP up to the 5750 RPM level, then the car begins detonating no matter what we do!

    I will begin with the results from yesterday's dyno session, then compare that to my dyno session last year, and the original data from 2009.

    To summarize our troubleshooting on the dyno yesterday:

    (1) AFR's were almost flat, running 91 Octane beginning at about 11.8 and trailing to 11.2. The car made approximately 350 WHP flat from about 5700 RPM to 7000 RPM in the first pull below.
    (Torque isn't plotted on this graph - waiting on more charts from the tuner)
    - Ignore the ghosted line for this time, it is just another run which didn't make it to redline




    (2) With AFR's flat and safe, and power flat from 5700 - 7000RPM we pulled timing from the top half of the map hoping to stop the detonation. We slowly backed out the timing......all the way down to 1-3 degrees advance at 19psi.

    If we were at the point of detonation, slowly backing out timing should have timed the burn and produced more power, but it constantly lost power and continued detonating all the way down to the 1-3 degrees advance level. Base timing on the car was 15 degrees checked with a non-advanced timing light while on the dyno.

    (3) Attempting to troubleshoot the problem, we changed the BKR7E plugs out and went from a 0.028" gap to 0.024" and went back to the original 7-10 degrees of timing advance. The car made 362 ft-lbs at 4580 RPM and 377 WHP at 5900 RPM. The exact same detonation problem continued from 5700 RPM to redline, but the car made more power with the timing added back into the picture. Something is not adding up.
    Sorry I haven't received the dyno graph yet, but here are screen shots from a video that I took to show peak TQ and WHP.








    I know that 7-10 degrees is a very conservative timing advance at the top end for these cars, and I think I should look into it further to find the problem. I know guys have mentioned that they run upwards of 18-20 degrees without issue, and even 25-30 degrees on higher octane fuel.

    To justify the hugely conservative number, I will post the timing tables from the car over a 5 year period. Before I get into that I want to say one thing......The dyno was loving the extra timing (making more power), so the only way to pick up on detonation was with proper head gear. We brought their master tech in to listen by ear in the engine bay while the tuner made a pull and he confirmed that it was definitely detonation, confirming the knock sensor / head gear noises.

    Now, in 2008 when the car was originally tuned I have no idea if the guys were using head gear to pick up on detonation. If they weren't wearing head gear with a knock sensor, and the car was making more power, they likely continued to add timing until it topped out, then backed it back to make it "safe"???

    If that is the case, I completely understand why they were confident in the tune, and I completely understand how they would have missed the detonation without head gear. So here are some comparisons:


    Dyno graph and ignition table from 2008 - Original tune:
    - Tuned with 93 Octane pump gas
    - Car made 379 WHP and about 370 ft.lbs at 18psi
    - Power drops off from 5800 RPM until it curves back up near redline
    - Consistent area for a drop-off in power - possibly undiagnosed detonation issues?
    - I used this tune for about a year before losing the engine to detonation
    - Timing was still initially conservating at about 9-13 degrees advance at 18 psi











    Ignition table from 2012 - Melted Harness:
    - Tuned with 94 Octane pump gas
    - Car was only tuned to 5900 RPM due to detonation issues
    - Tune was basically stepped up in 1000 RPM increments to tune driveability and stopped here once we observed detonation
    - At this level, the car made 347 WHP and about 309 ft.lbs at 17psi (basically untuned at high boost)
    - Consistent area for detonation to begin at 5750 RPM
    - Sorry I don't have the full dyno graph - I will post it if I can get it

    - We ended up melting the clips on the coil pack harness CYL #2 & #3 - and thought that this may have been causing our ignition / detonation problems, and stopped tuning
    - Turns out this was because when they initially did the swap they cut off the grounding wire on the harness and wired the harness into an HKS "ignition amplifier". While troubleshooting we bypassed the HKS box and in doing this removed the only ground that the harness had. We finished the day thinking that we had diagnosed the detonation issue - but we were wrong
    - When we began detonating the timing advance between 5750 and 7000 was about 6-11 degrees (still conservative) at 17psi
    - When we finished it was much lower at about 2-8 degrees advance at 17 psi - Still detonating!















    Dyno graph and ignition table from 2013 - Current tune:
    - Tuned with 91 Octane pump gas (All that is available out East)
    - Car made 377 WHP and 362 ft.lbs at 19psi (Very Consistent with the 379 WHP and about 370 ft.lbs at 18psi from 2008 when they used 93 octane fuel)
    - Power stays flat from 5750 RPM to redline (Representative dyno graph only - This was an intermediate run, I will post the full graph once I receive it)
    - Consistent area of detonation from 5750 RPM to redline - Consistent issue!
    - Timing is still very conservating at about 7-9 degrees advance at 19 psi
    - Note see the second ignition table at 1-3 degrees advance at 19 psi (Made 320 WHP only and still detonating throughout the RPM range!)
















    Now that the history is taken care of:
    - I've basically observed severe detonation on 3 engines over a 5 year period
    - AFR's are safe and flat in the mid 11's across the board
    - Car makes great useable and safe power up until about 5750 RPM
    - At this point power typically dips, and we observe detonation no matter what we do with the timing!
    - Fuel has varied from 93 to 94 to 91 octane with consistent detonation at a consistent RPM range
    - I also just noticed that boost drops off from about 5500 RPM to 6500 RPM before climbing near redline (not sure why this is happening - possibly because of the inefficient burn of detonation, then timing coming back into a better range near redline??)




    ..........
    Last edited by Solo_S14; 03-06-2013, 09:34 PM.

  • Solo_S14
    replied
    Dyno graph and ignition table from 2008 - Original tune:
    - Tuned with 93 Octane pump gas
    - Car made 379 WHP and about 370 ft.lbs at 18psi
    - Power drops off from 5800 RPM until it curves back up near redline
    - Consistent area for a drop-off in power - possibly undiagnosed detonation issues?
    - I used this tune for about a year before losing the engine to detonation
    - Timing was still initially conservating at about 9-13 degrees advance at 18 psi











    Ignition table from 2012 - Melted Harness:
    - Tuned with 94 Octane pump gas
    - Car was only tuned to 5900 RPM due to detonation issues
    - Tune was basically stepped up in 1000 RPM increments to tune driveability and stopped here once we observed detonation
    - At this level, the car made 347 WHP and about 309 ft.lbs at 17psi (basically untuned at high boost)
    - Consistent area for detonation to begin at 5750 RPM

    - We ended up melting the clips on the coil pack harness CYL #2 & #3 - and thought that this may have been causing our ignition / detonation problems, and stopped tuning
    - Turns out this was because when they initially did the swap they cut off the grounding wire on the harness and wired the harness into an HKS "ignition amplifier". While troubleshooting we bypassed the HKS box and in doing this removed the only ground that the harness had. We finished the day thinking that we had diagnosed the detonation issue - but we were wrong
    - When we began detonating the timing advance between 5750 and 7000 was about 6-11 degrees (still conservative) at 17psi
    - When we finished it was much lower at about 2-8 degrees advance at 17 psi - Still detonating!







    Dyno graph and ignition table from 2013:
    - Tuned with 91 Octane pump gas (All that is available out East)
    - Car made 377 WHP and 362 ft.lbs at 19psi (Very Consistent with the 379 WHP and about 370 ft.lbs at 18psi from 2008 when they used 93 octane fuel)
    - Power stays flat from 5750 RPM to 6500RPM
    - Consistent area of detonation from 5750 RPM to redline - Consistent issue!
    - Timing is still very conservating at about 7-9 degrees advance at 19 psi











    More info here:
    http://nissanroadracing.com/forum/en...tuning-experts


    Anything useful to help me calibrate / verify these knock events using the AEM EMS V1.......or anything odd you guys notice for SR20DET application in the tables / graphs I would love the feedback.

    Thanks all for the assistance!



    Leave a comment:


  • Solo_S14
    replied
    Hey so I haven't yet found a good e-tuner, but I have been working through through some issues / troubleshooting.
    One of which was the "Enginebasics" article that called out the AEM EMS V1 as missing an amplification circuit that the stock Nissan ECU uses for knock sensing.
    His fix was an early Saturn Resonant type sensor vs our non-resonant type sensors. I wasn't connecting the dots as to how the typical 300-500 millivolt output from one of those sensors wouldn't need amplification also, so I asked AEM on a thread in their forum that was dealing with this question - except they had answered for Version 2 which has additional knock tuning capabilities.

    I haven't yet received an answer, but there are a few things that may be of interest to you guys there:
    https://www.aemelectronics.com/?q=fo...-flat-response

    Since I'd also typed out an update and some questions over there, I'll post it here for anyone interested.
    Also, if you know of any reputable tuners that could help me out remotely, I would like to find one!

    For reference, I am running an SR20DET Blacktop with 87mm pistons @ 9.0:1 CR (86mm stock bore @ 8.5:1 CR), slightly larger Tomei 265 Poncams, Ferrea valvetrain, GT2871R, 740CC Injectors (380cc stock), and have backed away from EBC to MBC on advice of my tuner while we try to sort out these "knock" issues. For reference, I dyno'd about 380WHP / 360 TQ (always picking up the "knock" between 5000-6500RPM) before pulling the engine apart and finding zero damage. This has been a 5yr on again, off again problem - so any advice will go a long way!

    In short, if you guys have any ideas on things I can troubleshoot to either verify that the knock volts I am seeing are fine, or change to sort out why for example, I get knock retard without knock voltage regularly, I would really appreciate the help. The shots below outline some logs and scenarios that I've captured as a baseline - but really need the questions about the V1 answered above before I think I can move forward.

    Cheers!


    Last night I logged a 2nd gear, low load pull (-10psi to -4psi) from 3,000 - 7,000 RPM as a baseline for "noise".
    That highest reading was at 6480RPM, 0.16V which seems negligible if the amplification circuit works in the EMS V1. 6400RPM will be a common theme here:



    Here, I have a 2nd gear pull, full throttle, from 2000 - 7100 RPM.
    The AEM is pulling the maximum amount of timing (5deg) from 3850RPM (With Zero Knock Voltage?) onward.
    Most knock volts from 5600-6600RPM, with max readout of 0.76V at 6600RPM.
    ** Notice that at 1:49 there is a drop from 5700RPM to 5600RPM after a 0.3V knock event, then again at 1:50.5 from 7100RPM to 7000RPM.
    No such drop at the higher peaks of 0.33V at 6000RPM, 0.33V at 6450RPM, or 0.75V at 6600RPM. I am thinking this was just a one-time thing - but if you have any advice I am all ears.



    Then, a 3rd gear pull, with smooth RPM build - again the EMS pulls 5deg of timing from 3750RPM, with no Knock Voltage.
    A lot of high knock voltage events beginning at 5800RPM (0.4V), 6000RPM (0.95V), 6300RPM (0.8V), 6350RPM (2.85V), 6650RPM (2.55V), and 6900RPM (1.0V).



    For comparison, I tried a bit of a partial throttle sweep from 3500 - 7000 RPM in 3rd gear at up to 14psi of boost.
    A 0.33V reading at 4500RPM, the EMS pulled the maximum 5deg of timing through about 5,000 RPM.
    Then "relatively quiet" from 5,000-6,200 RPM, before spikes as high as 2.75V at 6470 RPM at 13psi.
    So the EMS is still pulling timing quite early, and we are seeing high knock volts throughout the power band, concentrating at ~6400RPM.



    One last 2nd gear pull, with peaks of more than 0.5V at 3900RPM (start of peak torque), 4800RPM (end of peak torque), 5550RPM (historic "knock point"), and 6450RPM (New favourite knock point).
    The EMS is pulling timing from 3900RPM onward - this time after a knock event vs the prior charts with timing pulled before knock events?? Still don't understand those ones.



    For reference, here are my current fuel and timing tables, as well as my last dyno graph(s) - all dyno plots at less advanced timing.
    Last night I added some timing to be more in the range of standard SR20DET tunes, but obviously it isn't helping me with the knock voltage.
    From what I gather, I can pull another 5-10 deg of timing, sacrifice the performance, and still "knock".....or sort out a better system to read and tune for verified knock events...


    Fuel - a few areas of ramp and hold, based on adjustments to logs



    Ignition - Early build, drop and hold throughout peak torque, then build again.
    Note that earlier dyno graphs would hold or drop timing following peak torque (fighting knock voltage / noise), with the exception of the 2008 tables which detonated an engine top death.



    Dyno Charts:

    2012 (Bold) vs 2013 (Thin)



    Leave a comment:


  • Solo_S14
    replied
    Hi guys - 3 years on - Again.

    After the issues documented above, I tore down the motor and it seems that (almost) everything was fine.
    No damage - with the exception that valves were literally kissing pistons enough to remove some carbon but not enough to damage anything permanently - valves were still sealing.
    Thinking possible valve float from the stock head / stock valvetrain that I went back to after the last failure, along with the little extra lift from the Tomei 256 poncams.

    Long story short I've rebuilt the engine - moved back to my full Ferrea valvetrain and ran a thicker HG. Also upgraded fuel system, fully rewired the car, new to me trans, etc.
    The car is back on the road and engine is breaking in - I need to get in touch with a reputable tuner that knows AEM (V.1) and knows SR20DET's.

    Looking back I think that my timing in higher RPM's was retarded too heavily - since the car was making more power (with the same "knock" - thinking it was mechanical all along) as timing was added.
    Who can I get in touch with (ASAP) to pull some logs, e-mail exchange some info, and finally get this thing dialed in?

    Note - no reputable dyno where I live, however access to a long offroad area - so looking for a "street tune" - pulls in all gears etc.
    Driveability is already very good, just looking for high load / full throttle tune.

    Thanks NRR!

    Leave a comment:


  • Solo_S14
    replied
    Do you have any logs of the knock sensor voltage and how you have the knock retard setup on this car? Also on most turbo cars detonation happens at peak torque where the cylinder pressure is highest. Therefore in this area the timing should be much lower etc.

    I don't have logs from the dyno - but I do have logs from last night. Pretty consistently I'm seeing noise start in the ~5500RPM range, and spikes at ~6500RPM. I've posted my timing and fuel maps below, along with (4x) logs.

    On a related note, I've attached further below a comparison of my 2012 and 2013 dyno charts. 2012 is in bold, and 2013 is the thin line. In both years, torque begins to drop off at 5500RPM, and then there is a noticeable drop-off in torque at 6500RPM (especially 2013). Last night we starting to pick up knock at ~5500RPM and it was usually peaking at ~6500RPM in the logs.

    My timing map is especially retarded between 5500RPM and 6500RPM @ ~15PSI. I assume that this was done to try to combat the knock that we are seeing.

    Logs attached for 10:45pm through 11:38pm – with the RPM called out in the titles. It’s sort of tough to see the peaks in knock with the cursor – but my cursor is usually over the peak (you can kind of see it). 11:09pm was the worst spike in knock @ 6500RPM by far.

    Maybe you guys can make some sense of the patterns against the timing table. To answer the other question, I don't see any timing being pulled on the charts, which tells me that the retard function either isn't set up, or it's not picking it up properly. Need to take a look at this tonight.



    2012 (Bold) vs 2013 (Thin)






    Timing Map



    Fuel Map



    10:45pm - Spike @ 6200RPM



    10:46pm - Spike @ 6400RPM



    11:09pm - Large Spike @ 6500RPM - it shows yellow in the screen capture



    11:38pm - Spike @ 6500RPM



    As always - any help is appreciated - trying to make some AutoX racing this weekend - so tonight I'll be troubleshooting what I can.

    Thanks guys.
    Last edited by Solo_S14; 11-04-2015, 11:19 AM. Reason: Split post due to excessive photo link length

    Leave a comment:


  • Solo_S14
    replied
    +1 on which CAS disk you're running? I would assume the 24-1 AEM disk given how much troubleshooting you've done, but maybe it's been missed over the years.

    Actually I'm pretty sure it's stock.......I'm going to find one and get it on order.


    In addition, I would not rule out the EMS. I know the v1's had some injector driver problems for a long time, and some other circuitry issues as well.

    I contacted AEM last year to send the unit back and have it tested. They ran through some basic things with me and then said that I'd be wasting my money to send it back. The theory was that either the unit would work, or it would be broken......an RPM bound issue (that isn't random or continuous) wouldn't be attributed to a physically damaged/deteriorating ECU.

    Long story short, I haven't tried another AEM V1 EMS because I don't know of anybody that has one to try.



    Damage, is it always on one cyl or on multiple? If on one cyl, is it always on the same cyl?

    The built motor that I lost in 2009 was due to severe detonation on Cyl #2. 40psi compression on that cylinder before pulling the motor.

    In 2010, I melted a stock motor - results as follows:
    - Piston #2 actually melted through the top and side
    - Piston #3 cracked ring land
    - Cylinder #2 aluminum build up and scoring on the wall

    Compression test:
    #1 - 133.5
    #2 - 0.0
    #3 - 91.5
    #4 - 136.0


    Coincidentally, when I melted a coil pack harness on the dyno in 2012 (I believe because the ground had been cut off for some reason) - I got a new harness, and haven' had an issue since - In 2012 I was hoping that this was my issue - but apparently not (details in the 1st post of this thread):

    Details:
    - We ended up melting the clips on the coil pack harness CYL #2 & #3 - and thought that this may have been causing our ignition / detonation problems, and stopped tuning





    I'm pretty sure that injectors have been moved around cylinders over the years / while troubleshooting - but never changed out.

    I wonder if an injector is causing an issue on one cylinder that isn't being picked up on the overall AFR readout?

    Do you guys think that this could be igniter related? I rebuilt all of the wiring this summer, so I shouldn't have any more damaged wire issues - but I wonder if a damaged igniter could be the issue?



    Ever shut the motor down as it detonates and read the plugs?

    No. This might be difficult now that I no longer have access to a dyno and don't want to die on the side of the highway


    Have you checked that all 4 cyl’s timing is stable from low to high RPM?

    No, but I will do this tonight - it might point to igniter issues / timing "scatter" on one cylinder, etc.


    Have you run EGT’s over the 4 cyl’s when on the dyno? Even a hand held infra-red will tell you a lot

    No.
    Do you think I'd be able to pick up on temperature differential across cylinders with a handheld unit, after just doing a few pulls on a highway in Mexico, with minor knock, and then pulling over to the side of the road to check? Or do you think this would have to be done basically while on the dyno?


    Have you got sufficient fuel flow?

    My AFR's are super rich. I've also got good fuel pressure.
    If my fuel line was undersized do you think that for some reason I could have flow issues that aren't picked up on in the AFR's or in the pressure? I wouldn't think so, but worth asking the question.


    What plugs do you usualy run?

    BKR7E. In 2013 I dropped my plug gap down from 0.028" to 0.024" while troubleshooting, but didn't notice a big change. I had coincidentally built torque a couple hundred RPM earlier, but I think that's because I dropped the boost down to a more efficient level.


    Does it do this at slightly lower boost (~14psi)?

    Yes. I've posted logs below at ~14-15psi from last night.....continuing issue.


    Have we verified fuel pressure is stable at all RPM's/load...what is the max injector duty cycle?

    I haven't logged fuel pressure, but I also haven't noticed anything out of the ordinary.
    I'll record my gauges tonight and play them back / report back. It won't be great data (no real resolution) - but I should be able to pick up on any fluctuation. Since my AFR's are so flat, I've never thought to look deeper. I'll also log my duty cycle and post it up.


    What turbo, exhaust housing and manifold are you running?

    GT2871R 0.64A/R. The manifold is a bottom mount Full Race prototype from ~8-9 years ago.


    Camshaft timing and specs?

    Tomei Poncams 256.
    Last edited by Solo_S14; 11-04-2015, 11:15 AM. Reason: Fixed Photo Links

    Leave a comment:


  • Solo_S14
    replied
    Hey guys!

    My bad for writing this thread and then disappearing for ....I don't know.....2 1/2 years :P

    Updates coming for my build thread - I got back at the car over xmas last year and it's now back up and running. A few teaser pics until I can get some time to update that thread.

    I depinned and rebuilt the engine harness over the winter, and then over the summer I decided to cut everything that wasn't essential out of the main dash harness:














    Now that I've (hopefully) got everyone's attention - I'll answer the questions that I saw throughout the thread, and post my latest tables and logs - as I'm still seeing the issue......
    Last edited by Solo_S14; 11-04-2015, 11:07 AM. Reason: Fixed Photo Links

    Leave a comment:


  • enerj
    replied
    Ya Solo, ever get any luck on this one? Do you still think this is ECU related or could engine setup be playing a role?

    Leave a comment:


  • wanabgts
    replied
    just realized someone resurrected this thread haha

    zack

    Leave a comment:


  • wanabgts
    replied
    Do you have any logs of the knock sensor voltage and how you have the knock retard setup on this car?

    Also on most turbo cars detonation happens at peak torque where the cylinder pressure is highest. Therefore in this area the timing should be much lower etc.

    Backpressure can be a problem, but not usually at the lower power levels you are currently seeing. Are you using a

    Are you using the 24-1 trigger wheel that they recommend with this setup? And also how well is the timing synced?

    I have had problems in the past with timing "drift" when using the stock trigger wheels. Use a timing light and set a fixed timing map, then rev the car and verify the timing stays where its supposed to.

    If you need some real tech help pm me and i will send my work phone number.

    Zack

    Leave a comment:


  • mct3351
    replied
    Did the original poster ever resolve the issue?

    Leave a comment:


  • Def
    replied
    Originally posted by Jason M View Post
    Detonation usually happens at or after TDC for a number of degrees, as per Heywood.
    That's not what I've seen from combustion videos. I agree it can happen roughly around TDC, but significantly after TDC the clearance volume has opened up in the quench area, and there just isn't much fuel/air to really create another bit of burning.

    I forget the percentages, but quite a bit of fuel/air mixture has burned at TDC for an engine operating at MBT.

    Leave a comment:


  • p00t
    replied
    Originally posted by Tower240sx View Post
    ...and there is no mention of shrouding.
    Originally posted by p00t View Post
    You can see that the detonation is originating from under those pads as they hide the fuel/air mix in those regions from the flame-front.
    You can scratch it off the list then. I'm interested in seeing what the fix is for Solo_S14.

    Leave a comment:


  • Jason M
    replied
    Detonation usually happens at or after TDC for a number of degrees, as per Heywood.

    Leave a comment:


  • Def
    replied
    Originally posted by p00t View Post
    Removing the pads should lower your static CR .2 to .3 points. Easy to check before and after. You have both kinds of heads you can measure the CC on right?

    You are misunderstanding me with all of this. I did not say that the perimeter of the piston did not provide for quenching of the air/fuel. They do more than just quench which was the reason for my comment. Had I known my comment about not calling them quench pads would start a flame war then I would have gladly omitted it. You can call them quench pads it does not bother me.

    Yes If you read my original post I do discuss shrouding but not airflow through the valves. I am talking about shrouding of the flame front from the fuel and air in that area. This area is where detonation is occurring. Hmm, fresh air and fuel pocket... descending piston (expanding quench area)... very high heat and pressure...

    I posted to help Solo_S14 not debate. If he tries my suggestion and it helps then he can move on to get some racing done.
    Detonation usually happens before the piston reaches TDC (or at it). So that part of your theory is all wrong.

    Don't confuse seeing detonation damage on quench pads as them CAUSING detonation. They generally improve the quality of combustion by increasing the speed and quality of the combustion due to turbulence in the CC. This function does not increase the possibility of detonation.

    Leave a comment:

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