9krpmrx8's Boost Build Thread
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I looked at the diagram you posted but I need to physically locate the resistor and bypass it. I kind of suck at electrical stuff so I may need some help on doing this.
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Oh ****
. I knew that had something to do with the fuel pump, just didn't know it was a resistor. Thanks. So I just jump a wire across it to bypass it right?
You unplug it from the wiring harness, then jumper across the two pins in the wiring harness connector
The resistor reduces the voltage to the pump, by jumpering the two pins you are sending full voltage to the pump. Might run a bit rich at low rpms due to the higher pressure from the pump running at full speed, but you will be looking to see if the same pressure drop/jump occurs under the same conditions
The resistor reduces the voltage to the pump, by jumpering the two pins you are sending full voltage to the pump. Might run a bit rich at low rpms due to the higher pressure from the pump running at full speed, but you will be looking to see if the same pressure drop/jump occurs under the same conditions
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You unplug it from the wiring harness, then jumper across the two pins in the wiring harness connector
The resistor reduces the voltage to the pump, by jumpering the two pins you are sending full voltage to the pump. Might run a bit rich at low rpms due to the higher pressure from the pump running at full speed, but you will be looking to see if the same pressure drop/jump occurs under the same conditions
The resistor reduces the voltage to the pump, by jumpering the two pins you are sending full voltage to the pump. Might run a bit rich at low rpms due to the higher pressure from the pump running at full speed, but you will be looking to see if the same pressure drop/jump occurs under the same conditions
because if it doesn't then this likely means it is the resistor kicking in and out, not the pump
the issue with the Aeromotive pump is that is is super high flow likely way beyond anything you need. It may be a good pump, but you will be bypassing excessively due to it being oversize. Aeromotive also makes a nice pulse-modulated speed controller to slow the pump down to minimize the bypassing, but it is another not so cheap price added to the equation. In theory running it slower will add to the lifespan. so as always ...
speed is only money, how fast can you afford to go?
the issue with the Aeromotive pump is that is is super high flow likely way beyond anything you need. It may be a good pump, but you will be bypassing excessively due to it being oversize. Aeromotive also makes a nice pulse-modulated speed controller to slow the pump down to minimize the bypassing, but it is another not so cheap price added to the equation. In theory running it slower will add to the lifespan. so as always ...
speed is only money, how fast can you afford to go?
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because if it doesn't then this likely means it is the resistor kicking in and out, not the pump
the issue with the Aeromotive pump is that is is super high flow likely way beyond anything you need. It may be a good pump, but you will be bypassing excessively due to it being oversize. Aeromotive also makes a nice pulse-modulated speed controller to slow the pump down to minimize the bypassing, but it is another not so cheap price added to the equation. In theory running it slower will add to the lifespan. so as always ...
speed is only money, how fast can you afford to go?
the issue with the Aeromotive pump is that is is super high flow likely way beyond anything you need. It may be a good pump, but you will be bypassing excessively due to it being oversize. Aeromotive also makes a nice pulse-modulated speed controller to slow the pump down to minimize the bypassing, but it is another not so cheap price added to the equation. In theory running it slower will add to the lifespan. so as always ...
speed is only money, how fast can you afford to go?
Well, not very fast
. It's definitely a learning process and if it is needed then I will get it.
Dude---save yourself some possible headaches and just get the S2 fuel pump assembly. Its solid and it works for our power level. I think Paul at Mazmart has a used one now.
Pretty sure it is not a "direct swap", it will fit with some mods, I am trying to think who put an S2 Fuel Pump in an S1??
I am not getting the same Part Numbers for the retaining Rings or Seals (also changed in S2).
Denny might know?
I am not getting the same Part Numbers for the retaining Rings or Seals (also changed in S2).
Denny might know?
all you have to do is to install a hose that fits between the tank siphon hose and the pump assembly--that a small piece of submersible hose with 2 worm claps. Then change the fuel tank level electrical connector that plugs into the underside of the pump assembly. The positive and negative wires have flipped sides between the models. Cut it, flip it and wire it--no problem. 15 minutes --its done
The ring and the gasket off the s1 works as it is still fitting the s1 tank? I have been running one for 2-3 years now. Its a much better pump assembly (cup, regulator, filter and siphon set up) AND its a better pump
Its designed to provide the oem fuel pressures and you dont have to modify the regulator.
Its the easiest solution that I know off for this level of power.
The ring and the gasket off the s1 works as it is still fitting the s1 tank? I have been running one for 2-3 years now. Its a much better pump assembly (cup, regulator, filter and siphon set up) AND its a better pump
Its designed to provide the oem fuel pressures and you dont have to modify the regulator.
Its the easiest solution that I know off for this level of power.
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I haven't had the fuel pressure issues again but I'm keeping an eye on it. I may swap in the extra stock pump I have, it's a low mileage unit out of an 07'.
every one of the Ga RX8 club members with the S1 model and that do hpde's have had to replace their fuel pumps at some point. Maybe we have dirty gas in Ga --IDK? But, still it has had to be done. They had good performance on the street , but they got the fuel starvation issues that have been discussed many times on this forum. Those that placed the s2 pump in their car have never had that problem to return. Those that continued to use the S1 design have had the problem return at some point.
Fuel supply is CRITICAL after you add FI to this engine. My advice is to not take chances with this. I know you are going to be canyon driving--(yeeHAW!) which is a lot like hpdes. So get that fuel system supply as rock solid as you can. I have no faith in the s1 fuel pump assembly.
Hell-- the cup was not even designed for the RX8--Mazda pulled it from somewhere. Who knows.
Fuel supply is CRITICAL after you add FI to this engine. My advice is to not take chances with this. I know you are going to be canyon driving--(yeeHAW!) which is a lot like hpdes. So get that fuel system supply as rock solid as you can. I have no faith in the s1 fuel pump assembly.
Hell-- the cup was not even designed for the RX8--Mazda pulled it from somewhere. Who knows.
every one of the Ga RX8 club members with the S1 model and that do hpde's have had to replace their fuel pumps at some point. Maybe we have dirty gas in Ga --IDK? But, still it has had to be done. They had good performance on the street , but they got the fuel starvation issues that have been discussed many times on this forum. Those that placed the s2 pump in their car have never had that problem to return. Those that continued to use the S1 design have had the problem return at some point.
Fuel supply is CRITICAL after you add FI to this engine. My advice is to not take chances with this. I know you are going to be canyon driving--(yeeHAW!) which is a lot like hpdes. So get that fuel system supply as rock solid as you can. I have no faith in the s1 fuel pump assembly.
Hell-- the cup was not even designed for the RX8--Mazda pulled it from somewhere. Who knows.
Fuel supply is CRITICAL after you add FI to this engine. My advice is to not take chances with this. I know you are going to be canyon driving--(yeeHAW!) which is a lot like hpdes. So get that fuel system supply as rock solid as you can. I have no faith in the s1 fuel pump assembly.
Hell-- the cup was not even designed for the RX8--Mazda pulled it from somewhere. Who knows.
all you have to do is to install a hose that fits between the tank siphon hose and the pump assembly--that a small piece of submersible hose with 2 worm claps. Then change the fuel tank level electrical connector that plugs into the underside of the pump assembly. The positive and negative wires have flipped sides between the models. Cut it, flip it and wire it--no problem. 15 minutes --its done
The ring and the gasket off the s1 works as it is still fitting the s1 tank? I have been running one for 2-3 years now. Its a much better pump assembly (cup, regulator, filter and siphon set up) AND its a better pump
Its designed to provide the oem fuel pressures and you dont have to modify the regulator.
Its the easiest solution that I know off for this level of power.
The ring and the gasket off the s1 works as it is still fitting the s1 tank? I have been running one for 2-3 years now. Its a much better pump assembly (cup, regulator, filter and siphon set up) AND its a better pump
Its designed to provide the oem fuel pressures and you dont have to modify the regulator.
Its the easiest solution that I know off for this level of power.
oh man, don't cut the wires, just swap the pin positions in the connector with a tiny jeweler screwdriver
http://www.4shared.com/file/37942260...n_Removal.html
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This pump has seen premix since day one. I may pull it to see what the sock looks like, but IIRC a filthy sock still has not restricted flow at all.


