What hp level does a single 044 pump need to be upgraded?
#16
05-05-2009, 10:49 AM
Registered User
so your saying that the the stock pump can only produce 576 bhp at the flywheel? Are you only considering the actual mechanical pump and not the venturi effect part of the pump that flows additional fuel?
Just about every tuned hybrid or k24 car is running more horsepower than that with no issues, so how can your number even be remotely true?
Just about every tuned hybrid or k24 car is running more horsepower than that with no issues, so how can your number even be remotely true?
I believe again that it has to do with efficiency. Most of the cars you're probably reffering to run on the street in "short" bursts. Track cars staying in boost for extended amounts of time would probably require a more adequate/reliable fuel system.
Another think to look at is the FPR which I believe works by controlling the fuel pressure at the rail, since this is a turbo car, I assume that the FPR is boost sensitive. Crushing it or going with a 5bar basically makes it more sensitive to boost/vacum. If the FPR closes/blocks a return line it provides a spike in the fuel pressure, making the injectors work at above given duty cycle. That approach is also utilized on other forcefed cars, however most consider going this route a band aid approach. This is why you see guys claiming to drop a full second at a track when finally getting an upgraded fuel system.
#17
05-05-2009, 11:01 AM
I believe again that it has to do with efficiency. Most of the cars you're probably reffering to run on the street in "short" bursts. Track cars staying in boost for extended amounts of time would probably require a more adequate/reliable fuel system.
Another think to look at is the FPR which I believe works by controlling the fuel pressure at the rail, since this is a turbo car, I assume that the FPR is boost sensitive. Crushing it or going with a 5bar basically makes it more sensitive to boost/vacum. If the FPR closes/blocks a return line it provides a spike in the fuel pressure, making the injectors work at above given duty cycle. That approach is also utilized on other forcefed cars, however most consider going this route a band aid approach. This is why you see guys claiming to drop a full second at a track when finally getting an upgraded fuel system.
Another think to look at is the FPR which I believe works by controlling the fuel pressure at the rail, since this is a turbo car, I assume that the FPR is boost sensitive. Crushing it or going with a 5bar basically makes it more sensitive to boost/vacum. If the FPR closes/blocks a return line it provides a spike in the fuel pressure, making the injectors work at above given duty cycle. That approach is also utilized on other forcefed cars, however most consider going this route a band aid approach. This is why you see guys claiming to drop a full second at a track when finally getting an upgraded fuel system.
#18
05-05-2009, 11:04 AM
I can name a few that track their cars that are pushing more power than that. I am sure that jean was talking pump mechanics and not anything to do with track, just what the max flow of a pump is. Again, I do not believe this is correct. That is basically saying that no car on this forum is producing more than 470 AWHP on a stock fuel pump. There are tons of dyno sheets showing 520+ at the wheels. Look at the K24/18g cars with injectors and how much they are pushing.
#19
05-05-2009, 11:10 AM
Honestly for safety (of your motor that is), I would do 2x 044's inline with a good Aeromotive or Weldon FPR. Make sure you get a good fuel pressure gauge so that you can always monitor the fuel pressure. I know most people hate Autometer, but my old electric one in my supercharged Cobra saved me a few times from going lean because I was able to realize that I had either A.) run low on fuel or B.) something was wrong somewhere and I was not getting the pressure I need. With a 1:1 style regulator your fuel pressure should rise for every pound of boost that you run. Now a FMU setup like some people insist on running (which I think is a bandaid) uses a 1:4 or 1:8 or even a 1:12 (maybe even higher) system where it shuts off the return basically and spikes the fuel pressure in order to allow you to make more power on a smaller injector.
With a stock intake pump and my 044 inline I know the car makes over 700rwhp in the right weather due to track times and mph that I have ran. I love the 044 because its fairly quiet, but if I could have done lines on the car I would def. have an Aeromotive or a Weldon fuel pump on the car, regardless of noise. I'd rather be safe than sorry. Weldon, Aeromotive, Magnafuel, etc. are all well known companys that produce good pumps for the amount of power you are hoping to push.
With a stock intake pump and my 044 inline I know the car makes over 700rwhp in the right weather due to track times and mph that I have ran. I love the 044 because its fairly quiet, but if I could have done lines on the car I would def. have an Aeromotive or a Weldon fuel pump on the car, regardless of noise. I'd rather be safe than sorry. Weldon, Aeromotive, Magnafuel, etc. are all well known companys that produce good pumps for the amount of power you are hoping to push.
#21
05-05-2009, 11:22 AM
Capacity of this pump, and apparently current draw, seem to be different depending upon who you speak to! Here's yet another claim as to capacity vs the Walbro - different amperage draw than what I've been told as well -> http://www.rx7club.com/showpost.php?...4&postcount=47
There are a couple of reasons that observed power could be different. One is BSFC - .55 sounds low to me. The other is, again, pump capacity - maybe the pumps flow more than folks realize? RC engineering has apparently "dyno'd them though.
Crushing the FPR will not change it's "sensitivity" nor will it turn it into an FMU. The diaphragm in the FPR is what effects it's ratio of change based on boost. Crushing it is much the same as turning the adjustment screw on an SX regulator.
Frankly, I'm pretty puzzled when someone swaps a fuel system into their car and finds horsepower gains. If the fuel wasn't there to make the power before then why wasn't the engine running lean? If boost is the **same airflow is the same and thus fueling shouldn't change! Gaining power from injectors or a pump makes zero sense unless boost changes. Someone please explain how this is supposedly occurring! Also, power for a given amount of airflow does NOT change that much with a leaner or richer mixture - timing is where the power is. I have varied power on a Supra, at WOT held steady state, from 10.5:1 to 12:1 and saw only small changes vs what I saw with timing which directly effects cylinder pressures. Fuel capacity shouldn't make a power change
Spray pattern differences maybe? That too seems dubious...
FWIW Jean is using hard numbers to make his claims, that they don't jive with observed numbers isn't his fault if his assumptions on capacity and efficiency ring true.
**Edit: Boost the same for the same turbos. Also - altitude should remain the same. Turbos at altitude spin harder to make equal boost and thus have different performance.
There are a couple of reasons that observed power could be different. One is BSFC - .55 sounds low to me. The other is, again, pump capacity - maybe the pumps flow more than folks realize? RC engineering has apparently "dyno'd them though.
Crushing the FPR will not change it's "sensitivity" nor will it turn it into an FMU. The diaphragm in the FPR is what effects it's ratio of change based on boost. Crushing it is much the same as turning the adjustment screw on an SX regulator.
Frankly, I'm pretty puzzled when someone swaps a fuel system into their car and finds horsepower gains. If the fuel wasn't there to make the power before then why wasn't the engine running lean? If boost is the **same airflow is the same and thus fueling shouldn't change! Gaining power from injectors or a pump makes zero sense unless boost changes. Someone please explain how this is supposedly occurring! Also, power for a given amount of airflow does NOT change that much with a leaner or richer mixture - timing is where the power is. I have varied power on a Supra, at WOT held steady state, from 10.5:1 to 12:1 and saw only small changes vs what I saw with timing which directly effects cylinder pressures. Fuel capacity shouldn't make a power change
Spray pattern differences maybe? That too seems dubious...FWIW Jean is using hard numbers to make his claims, that they don't jive with observed numbers isn't his fault if his assumptions on capacity and efficiency ring true.
**Edit: Boost the same for the same turbos. Also - altitude should remain the same. Turbos at altitude spin harder to make equal boost and thus have different performance.
Last edited by BLKMGK; 05-05-2009 at 11:25 AM.
#23
05-05-2009, 11:28 AM
Registered User
Capacity of this pump, and apparently current draw, seem to be different depending upon who you speak to! Here's yet another claim as to capacity vs the Walbro - different amperage draw than what I've been told as well -> http://www.rx7club.com/showpost.php?...4&postcount=47
There are a couple of reasons that observed power could be different. One is BSFC - .55 sounds low to me. The other is, again, pump capacity - maybe the pumps flow more than folks realize? RC engineering has apparently "dyno'd them though.
Crushing the FPR will not change it's "sensitivity" nor will it turn it into an FMU. The diaphragm in the FPR is what effects it's ratio of change based on boost. Crushing it is much the same as turning the adjustment screw on an SX regulator.
Frankly, I'm pretty puzzled when someone swaps a fuel system into their car and finds horsepower gains. If the fuel wasn't there to make the power before then why wasn't the engine running lean? If boost is the **same airflow is the same and thus fueling shouldn't change! Gaining power from injectors or a pump makes zero sense unless boost changes. Someone please explain how this is supposedly occurring! Also, power for a given amount of airflow does NOT change that much with a leaner or richer mixture - timing is where the power is. I have varied power on a Supra, at WOT held steady state, from 10.5:1 to 12:1 and saw only small changes vs what I saw with timing which directly effects cylinder pressures. Fuel capacity shouldn't make a power change Spray pattern differences maybe? That too seems dubious...
FWIW Jean is using hard numbers to make his claims, that they don't jive with observed numbers isn't his fault if his assumptions on capacity and efficiency ring true.
**Edit: Boost the same for the same turbos. Also - altitude should remain the same. Turbos at altitude spin harder to make equal boost and thus have different performance.
There are a couple of reasons that observed power could be different. One is BSFC - .55 sounds low to me. The other is, again, pump capacity - maybe the pumps flow more than folks realize? RC engineering has apparently "dyno'd them though.
Crushing the FPR will not change it's "sensitivity" nor will it turn it into an FMU. The diaphragm in the FPR is what effects it's ratio of change based on boost. Crushing it is much the same as turning the adjustment screw on an SX regulator.
Frankly, I'm pretty puzzled when someone swaps a fuel system into their car and finds horsepower gains. If the fuel wasn't there to make the power before then why wasn't the engine running lean? If boost is the **same airflow is the same and thus fueling shouldn't change! Gaining power from injectors or a pump makes zero sense unless boost changes. Someone please explain how this is supposedly occurring! Also, power for a given amount of airflow does NOT change that much with a leaner or richer mixture - timing is where the power is. I have varied power on a Supra, at WOT held steady state, from 10.5:1 to 12:1 and saw only small changes vs what I saw with timing which directly effects cylinder pressures. Fuel capacity shouldn't make a power change
Spray pattern differences maybe? That too seems dubious...FWIW Jean is using hard numbers to make his claims, that they don't jive with observed numbers isn't his fault if his assumptions on capacity and efficiency ring true.
**Edit: Boost the same for the same turbos. Also - altitude should remain the same. Turbos at altitude spin harder to make equal boost and thus have different performance.
I believe it has to do with the injectors. If they run above their dutycycle they're not gonna atomize the fuel in the best way. There is also the pulsewidth, which is what computer controls on the injector. With a bigger injector it's gonna be a smaller, more acurate, window when the same amount of fuel is injected.
#24
05-05-2009, 11:28 AM
Capacity of this pump, and apparently current draw, seem to be different depending upon who you speak to! Here's yet another claim as to capacity vs the Walbro - different amperage draw than what I've been told as well -> http://www.rx7club.com/showpost.php?...4&postcount=47
There are a couple of reasons that observed power could be different. One is BSFC - .55 sounds low to me. The other is, again, pump capacity - maybe the pumps flow more than folks realize? RC engineering has apparently "dyno'd them though.
Crushing the FPR will not change it's "sensitivity" nor will it turn it into an FMU. The diaphragm in the FPR is what effects it's ratio of change based on boost. Crushing it is much the same as turning the adjustment screw on an SX regulator.
Frankly, I'm pretty puzzled when someone swaps a fuel system into their car and finds horsepower gains. If the fuel wasn't there to make the power before then why wasn't the engine running lean? If boost is the **same airflow is the same and thus fueling shouldn't change! Gaining power from injectors or a pump makes zero sense unless boost changes. Someone please explain how this is supposedly occurring! Also, power for a given amount of airflow does NOT change that much with a leaner or richer mixture - timing is where the power is. I have varied power on a Supra, at WOT held steady state, from 10.5:1 to 12:1 and saw only small changes vs what I saw with timing which directly effects cylinder pressures. Fuel capacity shouldn't make a power change Spray pattern differences maybe? That too seems dubious...
FWIW Jean is using hard numbers to make his claims, that they don't jive with observed numbers isn't his fault if his assumptions on capacity and efficiency ring true.
**Edit: Boost the same for the same turbos. Also - altitude should remain the same. Turbos at altitude spin harder to make equal boost and thus have different performance.
There are a couple of reasons that observed power could be different. One is BSFC - .55 sounds low to me. The other is, again, pump capacity - maybe the pumps flow more than folks realize? RC engineering has apparently "dyno'd them though.
Crushing the FPR will not change it's "sensitivity" nor will it turn it into an FMU. The diaphragm in the FPR is what effects it's ratio of change based on boost. Crushing it is much the same as turning the adjustment screw on an SX regulator.
Frankly, I'm pretty puzzled when someone swaps a fuel system into their car and finds horsepower gains. If the fuel wasn't there to make the power before then why wasn't the engine running lean? If boost is the **same airflow is the same and thus fueling shouldn't change! Gaining power from injectors or a pump makes zero sense unless boost changes. Someone please explain how this is supposedly occurring! Also, power for a given amount of airflow does NOT change that much with a leaner or richer mixture - timing is where the power is. I have varied power on a Supra, at WOT held steady state, from 10.5:1 to 12:1 and saw only small changes vs what I saw with timing which directly effects cylinder pressures. Fuel capacity shouldn't make a power change
Spray pattern differences maybe? That too seems dubious...FWIW Jean is using hard numbers to make his claims, that they don't jive with observed numbers isn't his fault if his assumptions on capacity and efficiency ring true.
**Edit: Boost the same for the same turbos. Also - altitude should remain the same. Turbos at altitude spin harder to make equal boost and thus have different performance.
Changing a fuel system will net you 0 power unless you are running out of fuel and car is going lean. That is the only time you will see an increase in any kind of power because you added a bigger fuel line, fuel pump, injector, etc.
#25
05-05-2009, 11:31 AM
Frankly, I'm pretty puzzled when someone swaps a fuel system into their car and finds horsepower gains. If the fuel wasn't there to make the power before then why wasn't the engine running lean? If boost is the **same airflow is the same and thus fueling shouldn't change! Gaining power from injectors or a pump makes zero sense unless boost changes. Someone please explain how this is supposedly occurring! Also, power for a given amount of airflow does NOT change that much with a leaner or richer mixture - timing is where the power is. I have varied power on a Supra, at WOT held steady state, from 10.5:1 to 12:1 and saw only small changes vs what I saw with timing which directly effects cylinder pressures. Fuel capacity shouldn't make a power change Spray pattern differences maybe? That too seems dubious...
FWIW Jean is using hard numbers to make his claims, that they don't jive with observed numbers isn't his fault if his assumptions on capacity and efficiency ring true.
.
Spray pattern differences maybe? That too seems dubious...FWIW Jean is using hard numbers to make his claims, that they don't jive with observed numbers isn't his fault if his assumptions on capacity and efficiency ring true.
.
I wasn't placing blame with Jean for anything, I was just making a statement that the numbers do not match reality.
#28
05-05-2009, 11:50 AM
Well another tidbit - his BSFC number is actually pretty good. It's been awhile and I was reading it bassackwards. I know that some dynos are optimistic but I don't think that explains it either.
Prche951 - I understand. It's just nice that he's using numbers to back up his statements is all. I agree that something doesn't add up and I cannot explain it either! I worry about things like injector capacity, pump capacity, and well MAF capacity more than most so I've been puzzling over some of this for awhile. The car I'm purchasing has injectors, turbos, and no pump or MAF upgrade - it just laid down 600+RWHP. How it do dat? It's apparently out of MAF and maybe out of pump <shrug> If they are flooding the chambers with fuel to damp knock for big boost what kinds of A/F is observed? I've not seen evidence of that in the dyno charts I've seen with A/F displayed...
Adam - you might have hit on something, something I'd forgotten actually. When I was tuning AEM we used to try and time injection pulse with cam opening. We quickly ran into a problem - the cam wasn't open long enough for the pulse we needed at high power levels! We would have to pop the injector before the cam allowed intake air into the chamber. Perhaps, this is a long shot, power is being found because the smaller injector pulse is just waay too long at high power levels and a bigger injector is better timed for the cam? Smaller injectors are actually more accurate than bigger ones - less mass. With big injectors they can be so slow you command them to close before they actually really open, they dribble at idle. WOT this is less of an issue. This is partly why the BIG injectors are all P/H driven, they wouldn't idle well at all otherwise. Do tuners on these cars modify injector timing? Honestly on the AEM'd Supras we didn't find much power dorking with this that I remember but hey it's possible...
I think Powell may have hit on much of the issue with power increases honestly
It would still be nice to know why HP levels appear to exceed pump flow if indeed Jean's calculations and constant for BSFC and flow are correct. Anyone monitoring fuel pressure on their car want to chime in? 
Prche951 - I understand. It's just nice that he's using numbers to back up his statements is all. I agree that something doesn't add up and I cannot explain it either! I worry about things like injector capacity, pump capacity, and well MAF capacity more than most so I've been puzzling over some of this for awhile. The car I'm purchasing has injectors, turbos, and no pump or MAF upgrade - it just laid down 600+RWHP. How it do dat? It's apparently out of MAF and maybe out of pump <shrug> If they are flooding the chambers with fuel to damp knock for big boost what kinds of A/F is observed? I've not seen evidence of that in the dyno charts I've seen with A/F displayed...
Adam - you might have hit on something, something I'd forgotten actually. When I was tuning AEM we used to try and time injection pulse with cam opening. We quickly ran into a problem - the cam wasn't open long enough for the pulse we needed at high power levels! We would have to pop the injector before the cam allowed intake air into the chamber. Perhaps, this is a long shot, power is being found because the smaller injector pulse is just waay too long at high power levels and a bigger injector is better timed for the cam? Smaller injectors are actually more accurate than bigger ones - less mass. With big injectors they can be so slow you command them to close before they actually really open, they dribble at idle. WOT this is less of an issue. This is partly why the BIG injectors are all P/H driven, they wouldn't idle well at all otherwise. Do tuners on these cars modify injector timing? Honestly on the AEM'd Supras we didn't find much power dorking with this that I remember but hey it's possible...
I think Powell may have hit on much of the issue with power increases honestly
It would still be nice to know why HP levels appear to exceed pump flow if indeed Jean's calculations and constant for BSFC and flow are correct. Anyone monitoring fuel pressure on their car want to chime in?
#29
05-05-2009, 11:56 AM
Well another tidbit - his BSFC number is actually pretty good. It's been awhile and I was reading it bassackwards. I know that some dynos are optimistic but I don't think that explains it either.
Prche951 - I understand. It's just nice that he's using numbers to back up his statements is all. I agree that something doesn't add up and I cannot explain it either! I worry about things like injector capacity, pump capacity, and well MAF capacity more than most so I've been puzzling over some of this for awhile. The car I'm purchasing has injectors, turbos, and no pump or MAF upgrade - it just laid down 600+RWHP. How it do dat? It's apparently out of MAF and maybe out of pump <shrug> If they are flooding the chambers with fuel to damp knock for big boost what kinds of A/F is observed? I've not seen evidence of that in the dyno charts I've seen with A/F displayed...
Adam - you might have hit on something, something I'd forgotten actually. When I was tuning AEM we used to try and time injection pulse with cam opening. We quickly ran into a problem - the cam wasn't open long enough for the pulse we needed at high power levels! We would have to pop the injector before the cam allowed intake air into the chamber. Perhaps, this is a long shot, power is being found because the smaller injector pulse is just waay too long at high power levels and a bigger injector is better timed for the cam? Smaller injectors are actually more accurate than bigger ones - less mass. With big injectors they can be so slow you command them to close before they actually really open, they dribble at idle. WOT this is less of an issue. This is partly why the BIG injectors are all P/H driven, they wouldn't idle well at all otherwise. Do tuners on these cars modify injector timing? Honestly on the AEM'd Supras we didn't find much power dorking with this that I remember but hey it's possible...
I think Powell may have hit on much of the issue with power increases honestly It would still be nice to know why HP levels appear to exceed pump flow if indeed Jean's calculations and constant for BSFC and flow are correct. Anyone monitoring fuel pressure on their car want to chime in?
Prche951 - I understand. It's just nice that he's using numbers to back up his statements is all. I agree that something doesn't add up and I cannot explain it either! I worry about things like injector capacity, pump capacity, and well MAF capacity more than most so I've been puzzling over some of this for awhile. The car I'm purchasing has injectors, turbos, and no pump or MAF upgrade - it just laid down 600+RWHP. How it do dat? It's apparently out of MAF and maybe out of pump <shrug> If they are flooding the chambers with fuel to damp knock for big boost what kinds of A/F is observed? I've not seen evidence of that in the dyno charts I've seen with A/F displayed...
Adam - you might have hit on something, something I'd forgotten actually. When I was tuning AEM we used to try and time injection pulse with cam opening. We quickly ran into a problem - the cam wasn't open long enough for the pulse we needed at high power levels! We would have to pop the injector before the cam allowed intake air into the chamber. Perhaps, this is a long shot, power is being found because the smaller injector pulse is just waay too long at high power levels and a bigger injector is better timed for the cam? Smaller injectors are actually more accurate than bigger ones - less mass. With big injectors they can be so slow you command them to close before they actually really open, they dribble at idle. WOT this is less of an issue. This is partly why the BIG injectors are all P/H driven, they wouldn't idle well at all otherwise. Do tuners on these cars modify injector timing? Honestly on the AEM'd Supras we didn't find much power dorking with this that I remember but hey it's possible...
I think Powell may have hit on much of the issue with power increases honestly
It would still be nice to know why HP levels appear to exceed pump flow if indeed Jean's calculations and constant for BSFC and flow are correct. Anyone monitoring fuel pressure on their car want to chime in?
#30
05-06-2009, 06:55 AM
so your saying that the the stock pump can only produce 576 bhp at the flywheel? Are you only considering the actual mechanical pump and not the venturi effect part of the pump that flows additional fuel?
Just about every tuned hybrid or k24 car is running more horsepower than that with no issues, so how can your number even be remotely true?
Just about every tuned hybrid or k24 car is running more horsepower than that with no issues, so how can your number even be remotely true?
You're hurting my ears!
I have not see anyone giving a technical answer to the question asked so I am trying to help.
The 044 pump flows 200 Ltrs/Hr at 72 PSI as I mentioned earlier, after 20 minutes of operation. I am not talking about the stock 996TT pump, which in fact flows less than the 044.
In "free flow" mode, the 044 pump flows up to 300ltr/Hr. => 476lbs/Hr, however it will die before you turn around the first corner using it this way.
Absolute Maximum HP for a 996TT with a 044 in free flow mode= 476/0.55= 865 HP. Maximum HP with a single usable 044 fuel pump... <600 BHP provided it has larger injectors and FPR.
As to maximum HP with stock injectors and FPR, yes the numbers I posted are correct (around 460BHP@ 85% duty cycle), have the dyno checked if you get more than that.
Concerning BFSC, yes the lower the more efficient the engine. 0.55 is actually pretty low for a turbocharged car (meaning the engine is very efficient). N/A Porsche engines go lower than that.