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1G Mechanical Fuel pumps??

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SasaniFab

Proven Member
2,433
782
Dec 1, 2013
Mexico, Connecticut
Ok guys.....its looks like im going to go to a mechanical fuel setup. Main reason being, im tired of the electrical drain on my charging system and overall reliability. Plan is to run a magnus cam mount with an aeromotive pump.My question is regarding a lift pump. Ive been reading some running a lift pump from the tank to a sump in the bay and then to the mechanical. Some say they just run a mechical without a lift pump?
 
Running the mechanical without a lift pump is a pita to get the car fired up even with a check valve in line. I put a Wally 255 on a stock hanger tee'd into the -10AN feed line with a check valve. That pressurized the fuel line and the car fired up just like a electrical setup. My Wally took a crap right after I did it and I had to use a shot of ether to get it fired up after cranking for over 5 minutes to build enough pressure. I'm sure if you added a surge tank in the bay you could alleviate that but more weight if your running a fuel cell in the rear as well. Just keep in mind running just off the mechanical pump that is a ling way for it to pump the fuel up to the rail.
 
If you like using a drill to prime the car every time you start it, don’t use a lift pump.

If you’re going this far I’d ditch the stock tank and run a cell up front.
 
If you like using a drill to prime the car every time you start it, don’t use a lift pump.

If you’re going this far I’d ditch the stock tank and run a cell up front.
I was thinking running a wally lift pump to a sump in the bay to the inlet of the mechanical pump. This wouldnt be reliable?
 
I was thinking running a wally lift pump to a sump in the bay to the inlet of the mechanical pump. This wouldnt be reliable?
Running a pump to a surge tank that returns to the stock tank won’t prime the pump, unless you restrict the return to create pressure in the tank.
 
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I would recommend you check out another dsm member setup. His mechanical setup seemed to work great.
 
I have the stock tank sumped with a check valve and a T for the stock pump to prime the line. Works flawless.
Can you explain to me further your setup? So from the stock tank you run a fuel line to a tank in the engine bay. From the tank you run directly to the mechanical fuel pump inlet. Is this the line that requires a check valve? Also if i make a custom sump. Im thinking about sticking it were the battery used to be: It would require the inlet on the top of the tank. Then at the bottom the outlet that runs to the mechanical pump. Would i need to add another port somewere that runs back to the return?
 
I've been looking at the magnafuel mech pump to use with the Magnus drive. For some reason Magnus says you must use a waterman pump?
 
I personally dont like the idea of direct driving the fuel pump from the cams, think about what could happen if for some reason that fuel pump hits a piece of dirt of for any other reason wears out and wants to lock up? its going to cost you a jumped timing belt rather than just a jumped skinny little fuel pump belt, I prefer the out if theres a failure.
 
I personally dont like the idea of direct driving the fuel pump from the cams, think about what could happen if for some reason that fuel pump hits a piece of dirt of for any other reason wears out and wants to lock up? its going to cost you a jumped timing belt rather than just a jumped skinny little fuel pump belt, I prefer the out if theres a failure.
Has this been an issue? I guess at this level you need to accept some possibility of failure. This is gunna be hard deciding what to do.
 
I personally dont like the idea of direct driving the fuel pump from the cams, think about what could happen if for some reason that fuel pump hits a piece of dirt of for any other reason wears out and wants to lock up? its going to cost you a jumped timing belt rather than just a jumped skinny little fuel pump belt, I prefer the out if theres a failure.
I don't think that has happened to anyone. The hex portion of the pump is housed very nicely.

The diagram posted above is from my car.
 
Can you explain to me further your setup? So from the stock tank you run a fuel line to a tank in the engine bay. From the tank you run directly to the mechanical fuel pump inlet. Is this the line that requires a check valve? Also if i make a custom sump. Im thinking about sticking it were the battery used to be: It would require the inlet on the top of the tank. Then at the bottom the outlet that runs to the mechanical pump. Would i need to add another port somewere that runs back to the return?
You don't run a second tank in the bay. The check valve goes in the feed line to the pump which keeps fuel from draining back. You can use the stock return location on your tank.
 
I was just speaking with jeff bush, he said the only issue running directly off the cam gear is timing drift because of the load on the cam gear. He recommended I run off the crank if possible. Bah
 
Maybe for now Ill stick to the electric setup, im considering going to the jmfab 10 gallon cell. Maybe go to a single large pump in place of my multi pump setup. I was even thinking about welding in a sump to the stock tank. Decisions decisions :banghead:
 
I don't think that has happened to anyone. The hex portion of the pump is housed very nicely.

The diagram posted above is from my car.
Lets face it, it has bearings that can and more importantly WILL fail at some point, I run mine off of a belt so as to minimize the risk, also I like being able to easily and quickly disable the pump if I dont need it, I only run it when Im planning to run high boost.
 
Lets face it, it has bearings that can and more importantly WILL fail at some point, I run mine off of a belt so as to minimize the risk, also I like being able to easily and quickly disable the pump if I dont need it, I only run it when Im planning to run high boost.
Jeff bush said he personally never seen one fail, are you using the magnus kit that bolts to the factory alternator location
 
Maybe for now Ill stick to the electric setup, im considering going to the jmfab 10 gallon cell. Maybe go to a single large pump in place of my multi pump setup. I was even thinking about welding in a sump to the stock tank. Decisions decisions :banghead:

if you decide to go this route id suggest either the magnafuel mp-4303 or mp-4103 pumps. also if youre up to doing some fab work you can buy a cheap aluminum fuel cell and make your own bolt in. i went that route with my car and saved a few hundred dollars over the jmf.
 
Just go dry sump and run off the back of the patterson dry pump! Drive solved and also frees up from space. Also as it will be lower or as low as the tank it will kinda self flow to the mech pump easier
 
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