Maxing out Flow Force 640cc Injectors, but with low power? (With logs!)
#21
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So not 6600ft of elevation, then. The MAP sensor is correct, your boost gauge is correct, but something caused the baro sensor to read a bunch of vacuum on key-on when you started the car and created that log. That explains the discrepancy between your gauge and the MAP sensor. Tunerstudio reads the barometric reading and will correct the "boost" calculation to it. It's worth keeping an eye on the baro correction when tuning, just to be sure its not causing issues like it is for you.
Your high DC% is caused by a maxed-out fuel pump. Upgrade the pump.
Your high DC% is caused by a maxed-out fuel pump. Upgrade the pump.
#25
Adjusting the "Barometric Correction" setting under "General Settings" from "Two Independent Sensors" to "Initial MAP Reading", has resulting in the following:
- Tunerstudio Boost PSI is much closer to my Boost gauge. It went from recording a max PSI of 19.6 psi, to 16.6 psi - Mystery 1 Solved!
- Tunerstudio Barometer went from reading 80kPa to 99.4 kPa - Mystery 2 Solved!
- Tunerstudio Fuel: Baro cor went from reading 109.4% to 100.3% - Mystery 3 Solved!
Thanks again for everyone's help!! I have no idea why I changed my baro correction in the first place, but problem solved. I appreciate it!
Screen capture below and updated log attached.
Last edited by Carloverx; 12-03-2016 at 06:36 PM.
#26
Apologies for thread stealing. I'm having issues with my low boost Rotrex setup, and I've been reading through any troubleshooting thread I can find.
My Barometric Correction is set to "None". Should I change it? If I change it to Initial MAP reading, do I need to change any other values.
Thanks,
My Barometric Correction is set to "None". Should I change it? If I change it to Initial MAP reading, do I need to change any other values.
Thanks,
#27
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Apologies for thread stealing. I'm having issues with my low boost Rotrex setup, and I've been reading through any troubleshooting thread I can find.
My Barometric Correction is set to "None". Should I change it? If I change it to Initial MAP reading, do I need to change any other values.
Thanks,
My Barometric Correction is set to "None". Should I change it? If I change it to Initial MAP reading, do I need to change any other values.
Thanks,
#29
I have FF640s as well and get a PW of 12.5ms and AFR of 12.3 at 175kpa, which is my max.
You get 13.1ms and 11.3 AFR at 175kpa. So that's pretty damn good agreement.
Now at 210kpa I would roughly expect 210/175 * 13.1 ms = 15.7ms , just extrapolating from the lower value. Add 10-20% for reduced flow caused by lower pressure differential and we'd expect 17.3ms to 18.9ms.
You're at 18.7ms and your AFR is up. Your fuel system is maxed out. Convert to return-style system and upgrade pump.
You get 13.1ms and 11.3 AFR at 175kpa. So that's pretty damn good agreement.
Now at 210kpa I would roughly expect 210/175 * 13.1 ms = 15.7ms , just extrapolating from the lower value. Add 10-20% for reduced flow caused by lower pressure differential and we'd expect 17.3ms to 18.9ms.
You're at 18.7ms and your AFR is up. Your fuel system is maxed out. Convert to return-style system and upgrade pump.
My plan is to install a 190LPH-HP Walbro. Since I'm running a MegaSquirt (DIYPNP), I would NOT need to convert to a return-style style system and would NOT need to add an AFPR, correct?
#30
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Assuming there's no barometric correction, the correction should be 100.0%, or sea-level. For example, OP's logs showed a 9% fuel add at 80kpa of correction, which is like 6600ft of altitude. Small altitude changes, say anything under 1000ft, would result in a pretty small global change, enough that the fueling would probably still be within the error of MAT corrections. Thus, "should need no changes".
#31
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Assuming there's no barometric correction, the correction should be 100.0%, or sea-level. For example, OP's logs showed a 9% fuel add at 80kpa of correction, which is like 6600ft of altitude. Small altitude changes, say anything under 1000ft, would result in a pretty small global change, enough that the fueling would probably still be within the error of MAT corrections. Thus, "should need no changes".
So, while I don't fully understand the settings, your advice seems straightforward, and OP can easily determine if the correction goes to 100% after he turns off the correction.
#32
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My advice was for poormx, who said he has no baro correction right now. If you tune at sea level with no correction and then add correction, there should be no change.
Carloverx tuned at sea level with a 109% correction and needs to completely retune his car.
Carloverx tuned at sea level with a 109% correction and needs to completely retune his car.
#38
While I have more work to do, and I will possibly end up making a new thread, I feel like asking this here isn't too far off base:
Any guesses why a SEEMINGLY well running, newly built NB, running 65% DC (on FF 650cc's) at 15PSI, 93 oct, with a off brand 2871R would "only" be making ~200whp on a Virtual Dyno?
I know there could be a million reasons, but I SUSPECT my timing/boost is too mild 8.5:1 comp pistons. And while I do plan to continue to work on both (with the help of my det cans/ det muffs), it's obviously not something I want to be guessing at.
Note, my combo DOES have some very low end parts:
- head is stock,
- off brand log manifold and turbo elbow,
- off brand intercooler (full 2.5inch piping)
- exhaust has a cat (albeit from flyin miata through a 2.5inch exhaust)
- off brand muffler
Log attached in case anyone's interested in some go ol' internet diagnostics/speculation before i start messing with timing and boost again this weekend haha.
p.s. boost leak tests up to the throttle body hold boost rock solid.
(Edited post for injector size from 640 to 650)
Last edited by Carloverx; 12-31-2016 at 02:32 PM.