Trying to get meth dialed in... Issues

J

JCam550

New member
I'm working with Torrie who is being great looking at log after log.  I'm having an issue that I can't seem to figure out.  As the car reaches 6000 rpm, I get knock.  I'm running 80/20 mix with the largest snow nozzle.  I've changed my plugs ( 0.28 gap) and replaced both upstream O2 sensors.  Anyone have any ideas?  I've attached my most recent datalog. 
Thanks in advance
 
I don't claim to be a meth expert but some general tuning rules still apply....I'm not sure if this is related...I wouldn't think but it looks this way...The closer to redline you get, you are running really rich...  .70 lambda and depending on what the stoic is for the gas/meth mix you are probably richer than 10.0 afr....I wouldn't think being too rich contributes to knock but direct injection is a different animal....Fomocosho knows about this....If he had it his way he would run 14.0 afr in boost lol

Your STFT's are really low too...You are dumping so much meth to it that the ECU is pulling a ton of fuel and it still can't get the afr's leaner....Ideally you would want to dump the same meth that you are but adjust the fueling in the tune(which is a mystery with ford's speed density) so that the stft's are near 1.0 that way you are spraying the correct amount of fuel to hit target afr's

The fueling is off...The ECU is pulling 30% when the stft's are .70 It's pulling the fuel because it doesn't know where the extra fuel(meth) is coming from

You could ask torrie to pull a couple degrees of spark out to see if the knock levels go down...I wouldn't like to see the knock sensors pulling 7 degrees...That getting a little high to me...If your knock sensors are working or don't work fast enough then knock will come...I don't like mine being more than 2-4

You can tell you are dumping a lot of meth....At high load/boost you have tons of fuel pressure. You do because the ECU isn't dumping a lot from the car's fuel system

Maybe you want to nozzle down for less of the 80/20 mix or maybe same nozzle but 50/50? Not sure what you can do with those kits...But you have a ton of fuel in there...But if you had less meth then your afr's and stft's should come up and that may actually help...Should want to see around .78-.80 lambda
 
Take a look at my first revision of my meth log. This is 100% meth though a 625ml/hr. AJ, maybe comparing these will tell you something additional. Its just the first revision so its not too hot but its something to compare to.

Also, i am at a .030 gap
 
Scott4957 said:
Take a look at my first revision of my meth log. This is 100% meth though a 625ml/hr. AJ, maybe comparing these will tell you something additional. Its just the first revision so its not too hot but its something to compare to.
Click to expand...

Ok scott....what rev are you on now with your meth tune?
 
Yeah scott, I'd say that's a conservative tune...Knock was good but it should be...Both of you guys were similar as far as boost commanded about 218kpa but scott your actual boost was lower and your spark was lower so it shouldn't have any knock activity

Similar behavior though...Scott look at your stft's...They flat line the ECU is pulling the max amount of fuel it can and you still are running richer than what is being commanded....You are in the .75 lambda range when you are commanding .80...It's trying to pull enough fuel so the afr is .80 lambda but there is just too damn much meth lol
 
AJP turbo said:
Ok scott....what rev are you on now with your meth tune?
Click to expand...

I'm on revision 2 now but do not have any logs yet. That was the first revision. Seems everyone is running that nozzle. I have a Torrie tuned meth log final from another user on the forum, I believe its 100% as well. Take a look at this and see what your thoughts are. His STFT's seem much better and don't drip below .78 until the top of 4th, zero knock.
 
Scott4957 said:
AJP turbo said:
Ok scott....what rev are you on now with your meth tune?
Click to expand...

I'm on revision 2 now but do not have any logs yet. That was the first revision. Seems everyone is running that nozzle. I have a Torrie tuned meth log final from another user on the forum, I believe its 100% as well. Take a look at this and see what your thoughts are. His STFT's seem much better and don't drip below .78 until the top of 4th, zero knock.
Click to expand...

.80 stft is pretty far off....Don't confuse it with lambda...You want stft's to be .95-1.05 if you your tune is really good then only 3%+- once trims stabilize
 
@ AJPTurbo...lol! Not true, I just want a fuel curve that matches my needs. Stoich to about 4-4.5K with enrichment increasing linearly to max around redline. In a perfect world I need is a tune that can maintain FRP over 2K the entire pull with E30 ;)

@ JCam I'd suspect you are knocking because you have too much fuel and you are wetting the snot out of the cylinder walls. The other possibility is that you are knocking off carbon deposits from the valves that are causing hot spots and preignition.

You don't need the same amount of meth up high as you do in the midrange cause you have plenty of fuel up top with the cam spun up. So it seems to me that you'd want it enriching heavy in the area the HPFP struggles and actually tapering off as revs climb just to provide some octane/cooling and not a ton of fuel volume.
 
Thanks for all the input guys.  I was noticing how rich it gets as it nears 6,000 rpm.  At first I was thinking maybe I was running out of air and the mix was getting rich.  But that doesn't seem to be the case.  The car pulls amazing up to 5800 rpm.

  There really isn't any way to taper off the meth once it's spraying.  It tapers on but once I hit 11 psi of boost, it's spraying full blast.  I actually ran into a similar thing running 50/50.  I was running the 1/4 mile and as I closed in on 95-100 mph, the knock set in.  That's when Torrie suggested moving up to 80/20. 
 
I wonder if adding E85 would lean it out? The car would try to pull fuel just the same, but with some E85 in the tank it would technically be delivering less fuel right?
 
JCam550 said:
Problem is that E85 stations are few and far between around here.
Click to expand...

Yeah its not really a fix, but I am sure if Torrie can't get where he wants it to be he will have you move to a smaller nozzle. I have plenty of E85 but don't really want to mix if I don't have to. I am curious if it would work thought.
 
JCam550 said:
There really isn't any way to taper off the meth once it's spraying.  It tapers on but once I hit 11 psi of boost, it's spraying full blast.  I actually ran into a similar thing running 50/50.  I was running the 1/4 mile and as I closed in on 95-100 mph, the knock set in.  That's when Torrie suggested moving up to 80/20.
Click to expand...

I wonder if moving to the 2 nozzle kit would do the trick. Without looking I can't remember exactly how it is controlled, the controller would have to look at RPM's and boost. Having the ability to run two smaller nozzles in the mid range and then one shutting off at the top of the RPM range might do the trick. I see now that you already have the Stage 3 kit. Maybe its just a matter of Torrie getting this thing dialed in. Are you using the portion that pulls voltage from the fuel pressure sensor? Are you using the second nozzle? 
 
Since the meth spray is static, it seems you would just need to command less fuel from the stock fuel system till you get to .80 or whatever target you're looking for.
 
FoMoCoSHO said:
Since the meth spray is static, it seems you would just need to command less fuel from the stock fuel system till you get to .80 or whatever target you're looking for.
Click to expand...
Right, the impression I was getting is that AJ is saying the car can't pull enough.

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