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Engine rpm doesn't increase above 7000 rpm

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Car : 2012 Subar STI EJ20 Tubo

I tried to run my car to rev limit but the RPM doesn't increase from around 7000 RPM.
I have checked all my guesses bug I couldn't find it.

My llg file was too big to upload so I exported as CSV.
Original llg is in my google drive.

Does any one have any guesses?

https://drive.google.com/open?id=1Qq5PQjLNRBmAzj4iTX6zCXBPa5sqRhpE

GVB-22L.pclr

log2.zip

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I only had a quick look.  A couple of things that look odd to me:

  1. Lambda is topped out at 0.65 @ 6500RPM, that is very rich and will take some serious ignition to ignite.  Have you tried running leaner?
  2. Exhaust cam is 35deg retarded @ 6500RPM, I dont know if this is normal, have you tried ex cam @ 0deg?

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Here's my theory!  

I think you've reached the MAP limit.

I expect car revs beyond 7000 rpm when not under load (ie MAP limit not reached)

Also noticed the knock threshold is exceeded (albeit at lower rpm, so not the cause of this problem).

image.thumb.png.dfe740bde981fd68d556d9cbb690acf7.png

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21 hours ago, Adamw said:

I only had a quick look.  A couple of things that look odd to me:

  1. Lambda is topped out at 0.65 @ 6500RPM, that is very rich and will take some serious ignition to ignite.  Have you tried running leaner?
  2. Exhaust cam is 35deg retarded @ 6500RPM, I dont know if this is normal, have you tried ex cam @ 0deg?

Thanks for your answer.

I am trying to make it more leaner.
But I am scared to blow my engine.
@Adamw
How much lambda are usually used in each boost conditions.
Ex. 0 MAP 0.9 Lambda, 0.5 MAP 0.8 Lambda, 1.5MAP 0.7Lambda

2. Exhaust cam 35 deg @ 6500 rpm is a bit higher than usual in normal ECU.
I will change and retry it !!


Thanks. 

image.png

13 hours ago, TimmyD said:

Here's my theory!  

I think you've reached the MAP limit.

I expect car revs beyond 7000 rpm when not under load (ie MAP limit not reached)

Also noticed the knock threshold is exceeded (albeit at lower rpm, so not the cause of this problem).

image.thumb.png.dfe740bde981fd68d556d9cbb690acf7.png


Thank you for your advice for the knock threshold.
I wasn't noticed that my ignition timing was retarded.
I learned that retard will be in per cylinder and will not be described in the Ignition timing(BTDC) log.
Thank you.

By the way, My Map limit was set to 265. So I tried with changing it to 300.
But it didn't work.

I will try collecting more logs in various occasion.

Thank you anyway !!
 

I thought the lambda is way much richer than my sensor can notice.(LSU 4.9)
Because it is using 3400cc/min at peak.
I have changed my target Lambda leaner but the actual Lambda didn't change at all.(Stuck at 0.67)

So I will carefully try to make it leaner around 0.7 and check it works.

Thank you.

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Out of interest, I just looked at my Target Lambda (as it was tuned by a professional tuner, I'm not experienced in this area!!)  and mine is 0.79 agreeing with Brad's recommendations.

 

 

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On 9/18/2018 at 10:20 PM, Brad Burnett said:

from my experience with the quad cam avcs, full throttle pull, exhaust cam will sit around 25-30deg.

when adam says the thing is rich, .65 is way to rich and I bet is causing misfire.  These engines work better around .78-.8 lambda.


I think your guess was right.
I have changed the lambda around .75 and it worked fine!
Thanks !

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