Siphon tube question
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Siphon tube question
I just got my Raptor 100 in the other day, what i'm wondering is do i need to change the siphon tube on my tank? I have a big line kit to the VP already, as i already have a holley blue pump mounted back by the tank, or can i just get the -6 an fitting to a barb and tie into the stock fuel line? thanks for any info...
Capn
Capn
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It depends.
Usually with that model year, there is not a high degree of in tank restriction. But, if you have the metal canister lines, you may have or develop leaks due to rust holes over time.
If there is low restriction, you can just install the pump in line and be done with it. If you have high fueling demands, put in the draw tube. The less resistance on the suction side the better.
The design of the Raptor is an on demand style. Or internally regulated. So, it can only draw as much fuel as the VP44 can consume or bypass.
Dave
Usually with that model year, there is not a high degree of in tank restriction. But, if you have the metal canister lines, you may have or develop leaks due to rust holes over time.
If there is low restriction, you can just install the pump in line and be done with it. If you have high fueling demands, put in the draw tube. The less resistance on the suction side the better.
The design of the Raptor is an on demand style. Or internally regulated. So, it can only draw as much fuel as the VP44 can consume or bypass.
Dave
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From: Airdrie, Alberta
That being said, I ran 150 GPH Fass with the stock pickup for quite sometime with no ill issues.
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If it is internally regulated, it means that it will draw X amount of fuel, deliver Y amount (whatever the VP takes), and bypasses the rest. If it is a 100 GPH, it will be drawing something close to 100 GPH from the tank all the time. Whatever the VP doesn't take, it will dump back to tank.
That being said, I ran 150 GPH Fass with the stock pickup for quite sometime with no ill issues.
That being said, I ran 150 GPH Fass with the stock pickup for quite sometime with no ill issues.
Regarding running a 150GPH pump on the stock pickup, again, it depends on the year. But we have many hours diagnosing, testing and correcting cavitation issues caused by high inlet vacuum. While the average guy may not notice it, the pump will almost always run quieter, cooler and more efficiently if that vacuum is decreased. We have seen as much as 100 lost HP come back from the simple addition of a Draw Straw.
And to that end, the bypass style fuel pump manufacturers include draw tubes in their kits for a reason.
Dave
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That is not correct. This is NOT a bypass style pump such as the AirDog or full FASS systems. There is an internal bypass that allows the pressure to remain constant. And the 100GPH and 150GPH are rated at zero head, or wide open port. At a given pressure, say 20psi, that flow drops significantly.
Regarding running a 150GPH pump on the stock pickup, again, it depends on the year. But we have many hours diagnosing, testing and correcting cavitation issues caused by high inlet vacuum. While the average guy may not notice it, the pump will almost always run quieter, cooler and more efficiently if that vacuum is decreased. We have seen as much as 100 lost HP come back from the simple addition of a Draw Straw.
And to that end, the bypass style fuel pump manufacturers include draw tubes in their kits for a reason.
Dave
Regarding running a 150GPH pump on the stock pickup, again, it depends on the year. But we have many hours diagnosing, testing and correcting cavitation issues caused by high inlet vacuum. While the average guy may not notice it, the pump will almost always run quieter, cooler and more efficiently if that vacuum is decreased. We have seen as much as 100 lost HP come back from the simple addition of a Draw Straw.
And to that end, the bypass style fuel pump manufacturers include draw tubes in their kits for a reason.
Dave
Where does the fuel go that is being bypassed internally? Just back to the inlet of the pump, instead of back to the tank?
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