Trying to get meth dialed in... Issues

JCam550 · May 02, 2016, 08:36:12 PM

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

AJP turbo · May 02, 2016, 09:55:08 PM

Well hey hey...let me fire up the puter....80 meth 20 water?

AJP turbo · May 02, 2016, 10:01:42 PM

try to re upload the log....Says wrong format and log is 0kb in size?

JCam550 · May 02, 2016, 10:04:26 PM

I'll try again.

JCam550 · May 02, 2016, 10:05:50 PM

Quote from: AJP turbo on May 02, 2016, 09:55:08 PM
Well hey hey...let me fire up the puter....80 meth 20 water?

yes, 80 meth, 20 water 625 nozzle

SHOdded · May 02, 2016, 10:17:36 PM

Danged load strikes again!

AJP turbo · May 02, 2016, 10:38:53 PM

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

Scott4957 · May 02, 2016, 10:55:39 PM

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

AJP turbo · May 02, 2016, 10:58:12 PM

Quote from: Scott4957 on May 02, 2016, 10:55:39 PM
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.

Ok scott....what rev are you on now with your meth tune?

AJP turbo · May 02, 2016, 11:09:27 PM

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

Scott4957 · May 02, 2016, 11:20:23 PM

Quote from: AJP turbo on May 02, 2016, 10:58:12 PM
Ok scott....what rev are you on now with your meth tune?

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.

AJP turbo · May 02, 2016, 11:45:52 PM

Quote from: Scott4957 on May 02, 2016, 11:20:23 PM
Quote from: AJP turbo on May 02, 2016, 10:58:12 PM
Ok scott....what rev are you on now with your meth tune?

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.

.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

FoMoCoSHO · May 03, 2016, 01:31:30 AM

@ 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.

JCam550 · May 03, 2016, 08:12:12 AM

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.

Scott4957 · May 03, 2016, 09:12:29 AM

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?