Fuel pressure datalog - how erratic is acceptable?
08-11-2018, 11:07 PM
#21
Thank you for the feedback.
Fitting information is noted, all my fittings are aeromotive, earls, maybe a few vibrant etc. i dont recall seeing any of the fittings and noticing a large internal diameter difference (but maybe there is?) . I am going from an 8an dual in magnafuel regulator to a dual 10an weldon regulator.
Fitting information is noted, all my fittings are aeromotive, earls, maybe a few vibrant etc. i dont recall seeing any of the fittings and noticing a large internal diameter difference (but maybe there is?) . I am going from an 8an dual in magnafuel regulator to a dual 10an weldon regulator.
08-13-2018, 01:21 PM
#22
Restricted User
My fuel pressure is all over the place.
Stock truck rails/regulator, boost/vacuum referenced.
I've just attributed it to such a big cam for a small engine and its bouncing vacuum causing issues with the regulator.
Stock truck rails/regulator, boost/vacuum referenced.
I've just attributed it to such a big cam for a small engine and its bouncing vacuum causing issues with the regulator.
08-18-2018, 04:27 PM
#23
9 Second Club
Before wasting money on ****....what logging rate are you using ? What sensor ? where is the sensor located ? What FPR...where is the pressure reference taken from and what size line ?
What you are seeing is not normal.
What you are seeing is not normal.
08-23-2018, 03:57 PM
#24
I agree whole heartedly re: not wasting money on **** Stevie. I asked around, called several fuel companies, called and texted several dyno tuners, etc.). Many of them relayed experiencing similar issues, none of them had any feedback re: results of using the Radium Damper product (including Radium themselves!!!). One suggested running a loop of rubber fuel feed to help the dampening effect (this cured their issue). That overall process resulted in some feedback (the most constructive from Pantera EFI) that led to my actions.
For sensor logging rates, do you know where I could see (and adjust) that in tunerstudios? I have not tackled this yet per my rational in the above posts re: apples to apples comparison.
The Sensor is the traditional $20 Ebay 1-5v fuel sensor. Confirmed "reasonably accurate (statically)" via against my mechanical Autometer fuel pressure gauge from 15psi - 65psi.
The Sensor is located at the "Y" junction of the fuel feed (10an split to two 8an) fuel rail feed (pre regulator)
FPR is a magnafuel - Dual 8an in, 8an out, boost referenced, fuel pressure follows MAP but is jagged/erratic.
Lines are 10an feed to dual 8an into 8an rails, 8an out to 8 an tank return, all stainless PTFE (per discussions with both Weldon and Magnafuel the fuel system is setup "right" or to their preference.)
If I continue to see improvements and results I will likely replace the Holley fuel rails with something from Pantera to allow my screw on dampers plus the OEM dampers. The goal is to get fuel pressure much less erratic, hopefully narrowing my tuning window resulting in a better tune and drive-ability.
For sensor logging rates, do you know where I could see (and adjust) that in tunerstudios? I have not tackled this yet per my rational in the above posts re: apples to apples comparison.
The Sensor is the traditional $20 Ebay 1-5v fuel sensor. Confirmed "reasonably accurate (statically)" via against my mechanical Autometer fuel pressure gauge from 15psi - 65psi.
The Sensor is located at the "Y" junction of the fuel feed (10an split to two 8an) fuel rail feed (pre regulator)
FPR is a magnafuel - Dual 8an in, 8an out, boost referenced, fuel pressure follows MAP but is jagged/erratic.
Lines are 10an feed to dual 8an into 8an rails, 8an out to 8 an tank return, all stainless PTFE (per discussions with both Weldon and Magnafuel the fuel system is setup "right" or to their preference.)
If I continue to see improvements and results I will likely replace the Holley fuel rails with something from Pantera to allow my screw on dampers plus the OEM dampers. The goal is to get fuel pressure much less erratic, hopefully narrowing my tuning window resulting in a better tune and drive-ability.
08-23-2018, 04:15 PM
#25
9 Second Club
Having tested a few cheap sensors when doing water injection and oil pressure tests...I have found their readings to be oddly erratic when compared to a better quality sensor.
I do not use MS, so cant comment on where you might find the logging rates. But for the "problem" you are seeing...as a test I'd like to be logging at around 50Hz at least then you'd get a better picture of whether it really is jagged or not..if logging slower, the bad graph may just simple be because of too slow a logging rate, combined with the cheap sensor ( and it may require some filtering )
But certainly fitment of the damper can do no harm.
I do not use MS, so cant comment on where you might find the logging rates. But for the "problem" you are seeing...as a test I'd like to be logging at around 50Hz at least then you'd get a better picture of whether it really is jagged or not..if logging slower, the bad graph may just simple be because of too slow a logging rate, combined with the cheap sensor ( and it may require some filtering )
But certainly fitment of the damper can do no harm.
08-23-2018, 05:36 PM
#26
TECH Addict
Sometimes the way the fuel logs are connected matters, I had one that just worked better with a Y feeding both sides and one that liked having them in a series.
I see less harmonics on return than non return systems.. YMMV..
I see less harmonics on return than non return systems.. YMMV..
05-02-2023, 10:42 AM
#27
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@liquidmx or anybody else, did you ever get this sorted out?
I've been fighting with the same issue. I initially noticed lean over 8000 rpm, couldn't richen it up. Then I finally noticed fuel pressure gauge going nuts on the dyno. At that point I installed a pressure sensor and started datalogging. I noticed voltage was dropping, hot wired it, still the same issue so I swapped on a larger alt pulley to bring the alt rpm down. I questioned my pump, went from a 255 to a 340.
I set my fuel pressure to factory thinking it will better work with the factory damper setup but up at stupid high rpm fuel psi starts yo-yoing 30psi and it leans out. I'd piggyback a radium if it works but as you noted, 4 years later can't find any real data on this.
I'm thinking to try another fpr and see if it deals with these fuel pressure fluctuations better. I'd love to try a full radium setup but I'm not keen on gambling.
I've been fighting with the same issue. I initially noticed lean over 8000 rpm, couldn't richen it up. Then I finally noticed fuel pressure gauge going nuts on the dyno. At that point I installed a pressure sensor and started datalogging. I noticed voltage was dropping, hot wired it, still the same issue so I swapped on a larger alt pulley to bring the alt rpm down. I questioned my pump, went from a 255 to a 340.
I set my fuel pressure to factory thinking it will better work with the factory damper setup but up at stupid high rpm fuel psi starts yo-yoing 30psi and it leans out. I'd piggyback a radium if it works but as you noted, 4 years later can't find any real data on this.
I'm thinking to try another fpr and see if it deals with these fuel pressure fluctuations better. I'd love to try a full radium setup but I'm not keen on gambling.