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Discussion Starter · #1 ·
Ok well my 99 rav4 L 4door awd 5speed with the 3sfe motor. Well it got a hole punctured in the fuel tank and I'm doing a rally style with it so I figure what better time to switch to fuelcell than now ..
Now I'm not looking to upgrade much to do this just this moment so I'm in need to know the stock fuelpump size so I can get an external pump that will pare up with the stock fuel regulator ..

Does anyone know max u can pump through stock regulator or the size of the stock fuelpump
 

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IMO, unless you can determine that the fuel pressure is dropping under maximum load a larger pump would only waste $$$.
 

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Discussion Starter · #4 ·
No there's no issue with the stock pump there's not issue at all again what is going on is I have a fuel tank leak and wile I'm ripping it out to replace it I'm just converting over to a fuelcell so I need to get a external fuelpump ect. The stock stuff just won't work
 

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Discussion Starter · #5 ·
I'm seeing it's hard to find tuning guides on the net for these cars and for that matter anything aftermarket that isn't universal or for another car lol that's all fine and good I guess as it will be more rewarding and rare to see one so done up


Again im going into making this car for rally racing I decided to do this when I took a gravel road at high speeds and she performed amazing ...it's no sti or evo but it's still a great platform for the rally
 

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I have an issue with my supra on hot days. 15 gallon cell with -8an lines and an aeromotive a1000. The probelm is that the fuel gets very hot in the cell with the car sitting in the sun. With the oversized pump and a return style fuel system, after running for a while, too much heated fuel is returned to the tank as the injector duty is low for a majority of the mapping. The heated fuel is then drawn into the pump. Between the suction of the pump and the heat, i have the liquid turning to vapor at the point of the pump. The pump can not pump vapor, and i get bucking under load and fuel pressure issues.

Answers are:
Park the car on days near 100f
Keep the car parked in the shade
Drive hard so injectors spray instead of returning unused fuel to tank

Or if i was interested
Install pump controller and retune
Add fuel cooling heat sinks in the fuel supply line to pump


Whatever you do, make sure to properly size the pump to demand based on injector size and mapping
 

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Stock fuel pressure under load and at idle is going to be the same. Fuel pressure spec is 44-50 PSI. Note that the regulator is in the tank, just after the fuel pump, and the lead going out to the injector rail is a dead end. If you are going to replumb the whole thing with a fuel cell and external pump, you'll need to add an external regulator and a return line too. Note that there is no vacuum hose connected to the regulator, so it is always 44-50, regardless of engine vacuum. And external adjustable regulator would be a good idea, although you might be able to Aggie-rig up the old internal regulator and route the return line back to your tank.
 
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