Id 1000 + aeromotive 340lph capability
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Originally Posted by wy2slow_z' timestamp='1363260618' post='22403248
also keep in mind the fb 340s relief is at 80psi. so at max boost your pump wont go much over that. currently going through the same prob.with 1000cc. bump up your injectors and lower pressure.
First of all thank you for your reply. Secondly I am sorry for my English but i didn't understand what you told me to do. Do you mean i have a lot of fuel pressure (4.5bar) for my aeromotive pump and i have to lower it? Or i have to lower my boost? The strange thing is that 3 years ago when i tuned my car with the walbro 255 and the kenne bell boost a pump i could have 1.55 bar without maxing out my injectors so i have the feeling there is something wrong with my new aeromotive pump.
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Originally Posted by S2000_FUN' timestamp='1363262826' post='22403281
[quote name='wy2slow_z' timestamp='1363260618' post='22403248']
also keep in mind the fb 340s relief is at 80psi. so at max boost your pump wont go much over that. currently going through the same prob.with 1000cc. bump up your injectors and lower pressure.
also keep in mind the fb 340s relief is at 80psi. so at max boost your pump wont go much over that. currently going through the same prob.with 1000cc. bump up your injectors and lower pressure.
First of all thank you for your reply. Secondly I am sorry for my English but i didn't understand what you told me to do. Do you mean i have a lot of fuel pressure (4.5bar) for my aeromotive pump and i have to lower it? Or i have to lower my boost? The strange thing is that 3 years ago when i tuned my car with the walbro 255 and the kenne bell boost a pump i could have 1.55 bar without maxing out my injectors so i have the feeling there is something wrong with my new aeromotive pump.
[/quote]
On my previous tune with the kenne bell and the walbro 255 the pump was running with 16 Volts cause of the kenne bell. That was of course when I was in boost and the kenne bell was activating. Don't know the fuel pressure I was running that time. Now after my Aeromotive fuel pressure regulator failure I change it with an AEM one and also installed the aeromotive 340 pump. We measured the fuel pressure now upon installation of the AEM fuel pressure regulator at 4.5bar. We also measured the Voltage on the relay which is before the pump under boost and it was showing a bit more than 13Volts
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If your base pressure is 4.5 (65psi)bar + 1.6(23.2) bar of boost pressure you are nearing 90psi at the rail this is too high IMO. Given the flow of the pump at this pressure you are exceeding its limitations.
Here is a handy web app I made to help with issues like these.
http://webpages.char...ump_web_app.htm
Here are the values I used:
625hp approximated
65psi(4.5 bar) base pressure
23psi(1.6 bar) of boost
AFR of 11.8
The chart shows that the pump isn't enough at ~90psi.
Turn the base pressure down to 3 bar(Will require a complete retune) or I guess you could bump up the voltage using the kenne belle boost-a-pump although this is not usually the recommended method of increasing capacity. The only need for 4.5 bar fuel pressure would be if you plan on making a lot more power on the 1000cc injectors. If that was your plan then you need more fuel pump then. A pump like a bosch 044 would be a bit better in that it flows much better at higher pressures than many other pumps. Not an easy drop in fuel pump though. The aero 340 looses roughly 200hp worth of fuel from 70psi rail pressure to 90psi rail pressure. At 70 this pump can supply roughly 820hp worth of fuel, at 90psi it can only flow 620 give or take. This is the area you are entering and simply reducing the pressure will give you a lot more pump.
Here is a handy web app I made to help with issues like these.
http://webpages.char...ump_web_app.htm
Here are the values I used:
625hp approximated
65psi(4.5 bar) base pressure
23psi(1.6 bar) of boost
AFR of 11.8
The chart shows that the pump isn't enough at ~90psi.
Turn the base pressure down to 3 bar(Will require a complete retune) or I guess you could bump up the voltage using the kenne belle boost-a-pump although this is not usually the recommended method of increasing capacity. The only need for 4.5 bar fuel pressure would be if you plan on making a lot more power on the 1000cc injectors. If that was your plan then you need more fuel pump then. A pump like a bosch 044 would be a bit better in that it flows much better at higher pressures than many other pumps. Not an easy drop in fuel pump though. The aero 340 looses roughly 200hp worth of fuel from 70psi rail pressure to 90psi rail pressure. At 70 this pump can supply roughly 820hp worth of fuel, at 90psi it can only flow 620 give or take. This is the area you are entering and simply reducing the pressure will give you a lot more pump.
Just saw that now!!! Couldn't be more helpful response. Thank you so much you and the others. It seems I am running a lot of fuel pressure then
Just a note. I have removed the kenne bell upon installation of the aeromotive pump cause like you said is not the recommended method. That was the reason I removed the walbro cause I wanted to remove the kenne bell
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Originally Posted by hybrdthry911' timestamp='1363263344' post='22403285
[quote name='S2000_FUN' timestamp='1363262826' post='22403281']
[quote name='wy2slow_z' timestamp='1363260618' post='22403248']
also keep in mind the fb 340s relief is at 80psi. so at max boost your pump wont go much over that. currently going through the same prob.with 1000cc. bump up your injectors and lower pressure.
[quote name='wy2slow_z' timestamp='1363260618' post='22403248']
also keep in mind the fb 340s relief is at 80psi. so at max boost your pump wont go much over that. currently going through the same prob.with 1000cc. bump up your injectors and lower pressure.
First of all thank you for your reply. Secondly I am sorry for my English but i didn't understand what you told me to do. Do you mean i have a lot of fuel pressure (4.5bar) for my aeromotive pump and i have to lower it? Or i have to lower my boost? The strange thing is that 3 years ago when i tuned my car with the walbro 255 and the kenne bell boost a pump i could have 1.55 bar without maxing out my injectors so i have the feeling there is something wrong with my new aeromotive pump.
[/quote]
On my previous tune with the kenne bell and the walbro 255 the pump was running with 16 Volts cause of the kenne bell. That was of course when I was in boost and the kenne bell was activating. Don't know the fuel pressure I was running that time. Now after my Aeromotive fuel pressure regulator failure I change it with an AEM one and also installed the aeromotive 340 pump. We measured the fuel pressure now upon installation of the AEM fuel pressure regulator at 4.5bar. We also measured the Voltage on the relay which is before the pump under boost and it was showing a bit more than 13Volts
[/quote]
A walbro 255 at 16 volts and 3bar base pressure will flow more fuel than the aero340 at 13.2 volts and 4.5 bar.
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Originally Posted by S2000_FUN' timestamp='1363264672' post='22403326
Thank you so much!!! We will lower the fuel pressure then and retune the car. Thankfully my tuner is a one my good friends so retune won't be the problem
Thank you
I will definitely come back to post up the result and fingers crossed I will confirm the high fuel pressure was the problem
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From: Tampa, FL
Can you confirm this? Just because you measured voltage at the relay, doesn't mean that's what the pump is getting, especially if you're using the stock wiring in the housing.
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Originally Posted by spectacle' timestamp='1363203560' post='22401771
Is the pump rewired directly at the pump terminals inside the housing, bypassing ALL stock wiring? If not, this could be your issue.
I asked this to my garage when we changed the pump. I was wondering if after removal of the kenne bell the pump had enough voltage. That's why we connected the voltage meter to the relay and did a voltage test measurement under boost. The voltage was measured on the relay. After the relay I have stock wiring to the pump and I never measured the actual voltage on the pump terminals. Do you reckon the stock wiring is not enough for 13+ Volts?
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From: Tampa, FL
Originally Posted by spectacle' timestamp='1363268977' post='22403459
[quote name='spectacle' timestamp='1363203560' post='22401771']
Is the pump rewired directly at the pump terminals inside the housing, bypassing ALL stock wiring? If not, this could be your issue.
Is the pump rewired directly at the pump terminals inside the housing, bypassing ALL stock wiring? If not, this could be your issue.
I asked this to my garage when we changed the pump. I was wondering if after removal of the kenne bell the pump had enough voltage. That's why we connected the voltage meter to the relay and did a voltage test measurement under boost. The voltage was measured on the relay. After the relay I have stock wiring to the pump and I never measured the actual voltage on the pump terminals. Do you reckon the stock wiring is not enough for 13+ Volts?
[/quote]
I can almost guarantee this is your problem. The stock wiring is not enough for pumps bigger than the Walbro 255. You need to rewire the pump directly all the way inside the housing and replace the stock wiring.