razorlab's simple build(s)
Nov 8, 2015, 09:59 AM
#256
Okay, did some logging today. For some reason Evoscan refuses to log ZTX User2 now, even though it's logging ZTX Boost and AFR just fine, so I had to log fuel pressure via Zeitronix logging software, which doesn't have RPM or TPS hooked up.
Either way it doesn't really matter as we can just follow boost and fuel pressure.
Here is one instance. Notice the next gear up, right into boost, the car goes really rich at almost one full point, then goes back to 11.8-11.9 after the initial boost hit.
No abnormal spikes in fuel pressure.
http://datazap.me/u/razorlab/fuel-pr...zoom=3865-4130
Here is a quick full throttle burst, rich at peak boost then going back to normal.
http://datazap.me/u/razorlab/fuel-pr...zoom=6777-6919
and another:
http://datazap.me/u/razorlab/fuel-pr...om=10118-10279
Here is a WOT Pull through 3rd,4th and 5th. In Evoscan so no fuel pressure logged. You can still see the rich dips going into every gear.
http://datazap.me/u/razorlab/misc-pu...2&zoom=208-398
Now I'm wondering if it might be the BOV opening....
Either way it doesn't really matter as we can just follow boost and fuel pressure.
Here is one instance. Notice the next gear up, right into boost, the car goes really rich at almost one full point, then goes back to 11.8-11.9 after the initial boost hit.
No abnormal spikes in fuel pressure.
http://datazap.me/u/razorlab/fuel-pr...zoom=3865-4130
Here is a quick full throttle burst, rich at peak boost then going back to normal.
http://datazap.me/u/razorlab/fuel-pr...zoom=6777-6919
and another:
http://datazap.me/u/razorlab/fuel-pr...om=10118-10279
Here is a WOT Pull through 3rd,4th and 5th. In Evoscan so no fuel pressure logged. You can still see the rich dips going into every gear.
http://datazap.me/u/razorlab/misc-pu...2&zoom=208-398
Now I'm wondering if it might be the BOV opening....
FWIW, my Evo 9 does the same thing on spool. It was really bad when I was pushing 26+ psi on the stock DV, and when I went to a better DV, it went away. However, its back again now that I'm running even higher boost (34+ psi peak). I suppose its possible that the DV is again opening slightly. Since I only run Port B on my Synapse DV, it would be easy enough for me to check by running Port A+B. Maybe I'll try that later today if its not raining. This is all on MAF of course. On SD, a leaking DV couldn't affect AFR.
Nov 8, 2015, 10:39 AM
#257
43-44psi with hose off
37-38psi with hose on
User2 in the logs is fuel pressure at the feed line, about 1" from the fuel rail hard line.
Last edited by razorlab; Nov 8, 2015 at 10:45 AM.
Nov 8, 2015, 04:34 PM
#261
Here, I subtracted Fuel Pressure logged vs boost pressure logged and added a column called "FP-boost":
http://datazap.me/u/razorlab/fuel-pr...zoom=5392-5547
Nov 8, 2015, 05:30 PM
#262
Rail pressure minus boost should always be equal to base pressure (43-44 psi for your setup). Your setup is showing higher 49-51 psi at WOT, so something is wrong with fuel pressure control. I see a pretty decent FP-boost spike right at the start of that log, probably where the full pump kicks into full pressure mode. The spike followed by the 50 psi FP-boost values indicates FPR overrun. What FPR are you running? Could you show me rail pressure minus boost for the portion of your logs before WOT? I'd like to verify that its 43-44 psi for offboost conditions.
Nov 8, 2015, 06:21 PM
#263
Rail pressure minus boost should always be equal to base pressure (43-44 psi for your setup). Your setup is showing higher 49-51 psi at WOT, so something is wrong with fuel pressure control. I see a pretty decent FP-boost spike right at the start of that log, probably where the full pump kicks into full pressure mode. The spike followed by the 50 psi FP-boost values indicates FPR overrun. What FPR are you running? Could you show me rail pressure minus boost for the portion of your logs before WOT? I'd like to verify that its 43-44 psi for offboost conditions.
So now looking at the log I think something is totally wrong with the Zeitronix boost sensor log as that sensor is logging at approx -19 at idle:
http://datazap.me/u/razorlab/fuel-pr...4&zoom=35-2434
Here is OEM MAP sensor vs Zeitronix boost sensor at idle, OEM is approx -10 while zeitronix is approx -19:
http://datazap.me/u/razorlab/misc-pu...9-23&zoom=0-41
So the math with the zeitronix sensor is probably all wrong.
Fuel pressure is approx 39 off boost. That is with the vac hose on.
Last edited by razorlab; Nov 8, 2015 at 06:27 PM.
Nov 8, 2015, 08:04 PM
#264
I think the ZT-2 is giving inHg for output when it goes into vacuum because -10 psi is -19 inHg. Kinda dumb. Maybe there is something in the software that tells the readout to stay in psi the entire time? But if you want to fix your logs, inHg is almost exactly 2*psi.
Nov 8, 2015, 09:18 PM
#265
http://datazap.me/u/razorlab/misc-pu...3&zoom=297-396
I'll have to take a look and see if I need to re-calibrate it or something... This is a little concerning as the pump controller is using the zeitronix sensor as MAP reference.
Nov 8, 2015, 10:01 PM
#266
Looks like it's off during positive pressure as well:
http://datazap.me/u/razorlab/misc-pu...3&zoom=297-396
I'll have to take a look and see if I need to re-calibrate it or something... This is a little concerning as the pump controller is using the zeitronix sensor as MAP reference.
http://datazap.me/u/razorlab/misc-pu...3&zoom=297-396
I'll have to take a look and see if I need to re-calibrate it or something... This is a little concerning as the pump controller is using the zeitronix sensor as MAP reference.
Nov 9, 2015, 07:56 AM
#268
My guess is that the ZT reading is the more accurate of the two boost values. The Kavlico pressure sensor they use is very accurate and has a very well-known scaling whereas the JDM 3-bar scaling is only an estimate based on my measurements many years ago comparing to dial gauges. But I assume you'll contact ZT to see what's up, in particular to verify whether it reports inHg in vacuum?
Nov 9, 2015, 02:13 PM
#269
Razor you can soften the AFR dip if you delay the "full voltage" setting on the pump controller, you could even raise that setting high enough to were the pump never runs at full power. This can be useful if your FPR can't cope with the amount of flow and you don't need all the volume the pump can produce.
Ultimately on the X I have not been able to completely eliminate the AFR dip in all conditions. I can remove it under specific conditions but as soon as you load the engine in a different RPM/load/temperature it dips rich again, even though it may hit the same load cells. I do know it happens more easily the more you use MAP for your load calculations.
Ultimately on the X I have not been able to completely eliminate the AFR dip in all conditions. I can remove it under specific conditions but as soon as you load the engine in a different RPM/load/temperature it dips rich again, even though it may hit the same load cells. I do know it happens more easily the more you use MAP for your load calculations.
Nov 9, 2015, 02:33 PM
#270
Razor you can soften the AFR dip if you delay the "full voltage" setting on the pump controller, you could even raise that setting high enough to were the pump never runs at full power. This can be useful if your FPR can't cope with the amount of flow and you don't need all the volume the pump can produce.
Ultimately on the X I have not been able to completely eliminate the AFR dip in all conditions. I can remove it under specific conditions but as soon as you load the engine in a different RPM/load/temperature it dips rich again, even though it may hit the same load cells. I do know it happens more easily the more you use MAP for your load calculations.
Ultimately on the X I have not been able to completely eliminate the AFR dip in all conditions. I can remove it under specific conditions but as soon as you load the engine in a different RPM/load/temperature it dips rich again, even though it may hit the same load cells. I do know it happens more easily the more you use MAP for your load calculations.