converting from single fuel pump to dual

[guibo09]

I want to run a surge tank in the engine bay that feeds a high pressure pump. however, it is recommended to use a low pressure volume pump in the tank, instead of the stock high pressure one.

i have a late model e30, and therefore i have a single in take high pressure pump. if my research is correct, the early e30s use a dual pump system, one high, one low pressure.

is it possible to take the low pressure pump from an early e30 and install it in my late model e30 tank? is it a direct fit?

[Liam]

1st: Why a surge tank?

The transfer pump from an early e30 will take some modification to fit in a late tank (and they do not produce all that much volume).

[guibo09]

1st: Why a surge tank?

The transfer pump from an early e30 will take some modification to fit in a late tank (and they do not produce all that much volume).

surge tank for the track.

what modifications will be necessary? lots of people seem to easily swap from dual to single, so i figured the other way around would be simple?

i dont need that much volume, just needs to keep a 1/2-1 L tank full. wont be running FI either.

[guibo09]

these pumps look pretty interchangeable to me, maybe a few light tweeks to make it work:

[jlevie]

surge tank for the track.

what modifications will be necessary? lots of people seem to easily swap from dual to single, so i figured the other way around would be simple?

i dont need that much volume, just needs to keep a 1/2-1 L tank full. wont be running FI either.

Are you experinecing fuel starvation problems in the turns? If the pump is good and the tank is free of rust, you should not have any problems with the OE configuration.

[guibo09]

Are you experinecing fuel starvation problems in the turns? If the pump is good and the tank is free of rust, you should not have any problems with the OE configuration.

to make a long story short, i wrecked my last car cuz of fuel starvation. i want to make sure that never happens again, even if it's a bit overkill.

[asubimmer]

to make a long story short, i wrecked my last car cuz of fuel starvation. i want to make sure that never happens again, even if it's a bit overkill.

how did fuel starvation cause you to wreck? Take responsibility for your actions. If you still feel like it had nothing to do w/ your poor driving then put in an extra few gallons before you go out. Prob solved...

[guibo09]

how did fuel starvation cause you to wreck? Take responsibility for your actions. If you still feel like it had nothing to do w/ your poor driving then put in an extra few gallons before you go out. Prob solved...

and how do you know it didn't, sitting behind a computer screen with no knowledge of the situation? i did take responsibility for my actions, i admit that i pushed too much when i had just had fuel starvations on the previous run. i should have taken it slower, but i figured the extra few gallons would have solved the problem, but it didnt.

anyway, at slalom entry at the top of 2nd gear, the fuel cut. think engine compression in 2nd gear times 2 or 3 since the throttle was half open. a sudden braking like that at corner entry sent me into a 4 wheel drift at 50mph towards a wall less than 30 feet away.

let me tell you, that wall came fuckin fast.

anyway, back to the topic at hand. i think im gonna keep my high pressure pump. if it's pumping with no fuel pressure regulator, i dont see how it can build pressure and it should act like a good volume pump.

[Hallen]

I think what others are trying to say is that you had a problem with the previous fuel tank/pump and that a surge tank really isn't necessary if you have a properly operating stock system. I understand your concerns though. Once bitten, twice shy as it were.

Is your car purely a track car or is it a street/track car? All the PRO3 guys eventually go with a replacement fuel system that includes a crash-worthy fuel tank in the trunk. However, I think (think, not for sure) that SpecE30 uses the stock tanks. You may want to check with those guys before going through the effort of modifying your fuel system. They race their cars hard and they don't have fuel starvation problems.

[guibo09]

I think what others are trying to say is that you had a problem with the previous fuel tank/pump and that a surge tank really isn't necessary if you have a properly operating stock system. I understand your concerns though. Once bitten, twice shy as it were.

exactly. anyway, the wreck wasnt even an e30.

but still, i want to be safe. the design of my late model e30 is very similar to my impreza, with a single in tank pump on one side of the tank. yes it may be baffled differently, but there always remains a risk.

i definitely dont want to upgrade to a race fuel system since this car will still be a DD in the summer. i want to implement a simple surge tank in the engine bay with an inline walbro to feed the injectors.

[asubimmer]

The stock system is fine. Don't blame your mistakes on the car. Use the money you were going to spend on this for track time instead. Goodluck!

[itsbrokeagain]

The stock system is fine. Don't blame your mistakes on the car. Use the money you were going to spend on this for track time instead. Goodluck!

wow. :hitler:

You sure do attack people on this forum.

Im interested myself in doing a surge tank setup. Nothing wrong routing the fuel lines to the trunk, fabbing up a tank in the trunk with a high pressure pump, and sending that line to the engine.

I plan to go road racing myself, so as long as the engine has plenty of fuel Im fine....

[guibo09]

wow. :hitler:

You sure do attack people on this forum.

Im interested myself in doing a surge tank setup. Nothing wrong routing the fuel lines to the trunk, fabbing up a tank in the trunk with a high pressure pump, and sending that line to the engine.

I plan to go road racing myself, so as long as the engine has plenty of fuel Im fine....

yeah ive pretty much decided to ignore this idiot. seems like anyone doing something against his pseudo engineering can't be right.

anway, i think i prefer placing the surge tank in the engine bay since there is decent vertical room without sacrificing trunk space. also, it's safer since you wont be moving fuel into a non-fire shielded area (would fail inspection).

[asubimmer]

lol all I'm saying is it isn't needed in an e30. Go to the track and see how many e30's use a surge tank. I doubt you will even find one. If you want to waste your money on it then fine, its not like I'm paying for it. But hey if you do put one in then next time you smash your car you are gonna have to make up another reason why it wasn't your fault.

[erik325i]

lol all I'm saying is it isn't needed in an e30. Go to the track and see how many e30's use a surge tank. I doubt you will even find one. If you want to waste your money on it then fine, its not like I'm paying for it. But hey if you do put one in then next time you smash your car you are gonna have to make up another reason why it wasn't your fault.

Give it up. He asked a simple question.
Mentioning that you think the surge tank is not needed is fine. You don't need to keep posting over and over saying the same thing.
Using a surge tank will not hurt anything.

Erik