How to correctly fit the c5 filter regulator?
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How to correctly fit the c5 filter regulator? Hi All
First post so hope it is ok to drop it here as it isn't strictly LS1 related.
I am using a Corvette c5 filter regulator to allow me to fuel inject an old lotus 7. I want to deadhead the fuel system, so the c5 filter regulator seems ideal. Is there a correct way to fit this part? at the moment I have it vertical and next to the tank, with the outlet fuel line pointing downwards and mounted lower than the tank return port. My main concern is getting air into the fuel system during hard cornering, the tank has an internal high pressure pump, but the baffles are not the best and it may suck air briefly during autocross style abuse (which it will be getting). If the return port on the filter regulator is at the top, will any air be bled back via the fuel return line?
Did a bit of quick maths and I think I need ~5cc/second at full throttle, and filter capacity is ~300cc, so ~60 sec of fuel in the filter before air goes into the line. The engine will not tolerate a lean condition for more than a few seconds before it all gets a bit melty so want to figure out if it will bleed out any air via the return or if i should rethink my fuel system.
Thanks
First post so hope it is ok to drop it here as it isn't strictly LS1 related.
I am using a Corvette c5 filter regulator to allow me to fuel inject an old lotus 7. I want to deadhead the fuel system, so the c5 filter regulator seems ideal. Is there a correct way to fit this part? at the moment I have it vertical and next to the tank, with the outlet fuel line pointing downwards and mounted lower than the tank return port. My main concern is getting air into the fuel system during hard cornering, the tank has an internal high pressure pump, but the baffles are not the best and it may suck air briefly during autocross style abuse (which it will be getting). If the return port on the filter regulator is at the top, will any air be bled back via the fuel return line?
Did a bit of quick maths and I think I need ~5cc/second at full throttle, and filter capacity is ~300cc, so ~60 sec of fuel in the filter before air goes into the line. The engine will not tolerate a lean condition for more than a few seconds before it all gets a bit melty so want to figure out if it will bleed out any air via the return or if i should rethink my fuel system.
Thanks
Your best bet is to get a bucket, a sponge, Holley Hydro Mat, or etc, whatever it takes to make sure your pump never pulls in air. You are slowly killing the pump and then sending air to a system that has a large dead head line after the filter with no way to purge that air other than through the motor.
You next best bet is to do a regulator on the fuel rail and keep it high to try and get the air to return to the tank and never go into the motor, but that will still slowly kill the pump.
I have not cut open that filter/reg before to say mounting it one way or the other might be better if you don't just do i right and make sure never pulls air.
You next best bet is to do a regulator on the fuel rail and keep it high to try and get the air to return to the tank and never go into the motor, but that will still slowly kill the pump.
I have not cut open that filter/reg before to say mounting it one way or the other might be better if you don't just do i right and make sure never pulls air.
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Thanks for the input
Hydromat looks interesting, not seen that before in the uk. No one has ever figured out a decent internal swirl pot (guessing your bucket?) on our tanks as that would be my preference. I have an image of a cut up c5 filter regulator Cut up c5 filter/regulator, mine is mounted with the inlet and return at the top, below the tank return, so air "should" rise into the centre connection and be pushed out of the return back to the tank. I have ignition cut on low pressure set up on my ecu, but it is a bit brutal and a last resort sort of thing to save the engine, trying to get it to work more like a traction control, but it is a bit above my paygrade trying to figure that option, so at the moment it is just a hard cut on low pressure. Might spin, but should keep the engine.
Hydromat looks interesting, not seen that before in the uk. No one has ever figured out a decent internal swirl pot (guessing your bucket?) on our tanks as that would be my preference. I have an image of a cut up c5 filter regulator Cut up c5 filter/regulator, mine is mounted with the inlet and return at the top, below the tank return, so air "should" rise into the centre connection and be pushed out of the return back to the tank. I have ignition cut on low pressure set up on my ecu, but it is a bit brutal and a last resort sort of thing to save the engine, trying to get it to work more like a traction control, but it is a bit above my paygrade trying to figure that option, so at the moment it is just a hard cut on low pressure. Might spin, but should keep the engine.
No, problem. Sort of exercise for the mind when people bring up odd new issues.
I guess that is your best bet based on the pictur, but the filter has to fill a 1/3 of the way with air before it pushes into the filter and can return to tank. That is only if it can separate well enough at speed. Now the larger issue I see is the inlet is shorter than the filter material and will be shooting through the pocket of air for ever once it's filled and that will likely mean a constant mixture of random air into your rails. Your best bet is probably to get the hyrdomat and take the pain of that price now with the thought of it saving you the cost of pumps and maybe motor later. Best to cry about it once.
I guess that is your best bet based on the pictur, but the filter has to fill a 1/3 of the way with air before it pushes into the filter and can return to tank. That is only if it can separate well enough at speed. Now the larger issue I see is the inlet is shorter than the filter material and will be shooting through the pocket of air for ever once it's filled and that will likely mean a constant mixture of random air into your rails. Your best bet is probably to get the hyrdomat and take the pain of that price now with the thought of it saving you the cost of pumps and maybe motor later. Best to cry about it once.
I had a similar problem with my Exocet. It uses a stock 10gal Miata tank. On the road course it would suck air on a hard left turn when it got about 6-7gallons low. I installed a Holley Hydromat, and problem solved. It will run just fine down to about 1 gallon in the tank.
The Hydromat appears to be a little expensive. But they're easy to install, and a whole lot cheaper than a surge tank, swirl pot, or fuel cell.
The Hydromat appears to be a little expensive. But they're easy to install, and a whole lot cheaper than a surge tank, swirl pot, or fuel cell.
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Hi Bob
That is pretty much the conclusion I have come to, trying to find out how big the internal baffle space is so I can buy the best shaped option, the tank has some gated divider plates, but the compartments are quite big, so not that effective on low fuel, and it may let me use the 7l of fuel capacity that it never seems to use. I think the filter sock may not actually pick up from the bottom of the tank.
That is pretty much the conclusion I have come to, trying to find out how big the internal baffle space is so I can buy the best shaped option, the tank has some gated divider plates, but the compartments are quite big, so not that effective on low fuel, and it may let me use the 7l of fuel capacity that it never seems to use. I think the filter sock may not actually pick up from the bottom of the tank.
