Evo X upgrades - Page 92

**scheides** · 05-25-2011

Ok that is my big beef with the aeromotive pump, why on earth would they wire it backwards from the product they are directly trying to compete against? Makes ZERO sense!

Glad you figured it out, that is just nuts!

**mlomker** · 05-26-2011

The polarity fix got the pump working, of course. The problem is that it has too much flow for the return on the stock hanger and is pressuring the surge tank to ~6psi. This causes it to spring a leak at the 044 pump connection.

I think I've seen forum posts about ways to make the return less restrictive. Otherwise I'll need to downgrade that pump to a 255.

**goodhart** · 05-26-2011

Would it be easier to swap in a larger return line? like -6 or -8 or something? What size is it now? Then you could have the extra flow you may need down the road, AND have it not overflow. Either way, glad to hear ya got it working!

**mlomker** · 05-26-2011

Quote:

Originally Posted by goodhart

Would it be easier to swap in a larger return line? like -6 or -8 or something?

The line isn't the restriction, it is within the stock hanger. They have a restrictor that creates the venturi effect used to pull fuel over from the other saddle in the tank. It was designed with stock flow in mind. Some people drill it out a bit but it's a little risky because if you drill it out too far then it stops drawing from the other saddle and you run out of gas with the gauge reading 1/4 tank.

**Kracka** · 05-26-2011

Sell and replace with stock, 255, or DW300?

LMK if you need a stock pump.

**mlomker** · 05-26-2011

Quote:

Originally Posted by Kracka

Sell and replace with stock, 255, or DW300?

We will see. I have a pair of 255 in the Full Blown hanger so I could pull one to test with.

Discussion about increasing the return capacity:
http://www.evoxforums.com/forums/showthread.php?t=28036

**mlomker** · 05-26-2011

It looks like air in the fuel lines is my problem. I purged the surge tank/return and now that's all happy. I snugged up the surge tank fittings so no more leak.

Right now I'm getting no fuel pressure to the rail so I suppose there's air in that line as well. I ran out of lunch hour so I'll have to decide what to do with that later.

**asshanson** · 05-26-2011

Air in the feed line shouldn't matter, if your pump is running it should push those air bubbles out.

**mlomker** · 05-26-2011

Spend quite a few hours experimenting. It certainly appears that the return line for the stock in-tank hanger is too restrictive. I just swapped a regular 255 into the hanger and will give it a try in the morning. The car seems to run fine if I leave the in-tank pump unplugged but everything I tried with it running would result in fuel pressure going to 0 at the motor. I even swapped in the Bosch instead of the Jays 044 and the symptoms were identical.

I hope the 255 works. If not then I'll probably try cutting off the return hose in the hanger to bypass the restrictive return/siphon. Too many people eyeballing my car...leaving it parked in one spot for too long is making me nervous. I need to move that car tomorrow...even if that means running off the surge tank and stopping half-way home to refill it.

**Halon** · 05-26-2011

Sounda like a big PITA over a deng fuel pump setup. I can't believe that nobody has come up with a solution for those cars yet.

**Murlo26** · 05-26-2011

Mine works fine...ya know, when my car works lol.

edit: for going straight

**mlomker** · 05-26-2011

Quote:

Originally Posted by Murlo26

Mine works fine...ya know, when my car works lol.

edit: for going straight

Not sure if BlaqOPs mods the return or not. Gotta keep in mind that an Aeromotive 340 flows over 425lph at low pressures. That single pump flows about the same as a double pump at full honk.

http://forums.evolutionm.net/evo-eng...acing-top.html

**Murlo26** · 05-26-2011

Quote:

Originally Posted by mlomker

Not sure if BlaqOPs mods the return or not. Gotta keep in mind that an Aeromotive 340 flows over 425lph at low pressures. That single pump flows about the same as a double pump at full honk.

http://forums.evolutionm.net/evo-eng...acing-top.html

The other pump on a blaqpops isn't another 255 though, its a mustang gt500 pump or something that flows a lot from what i understand.

Regardless, ya those flow a lot.

**mlomker** · 05-26-2011

Quote:

Originally Posted by Murlo26

The other pump on a blaqpops isn't another 255 though, its a mustang gt500 pump or something that flows a lot from what i understand.

It is ~280lph pump and it is Walbro-brand. I looked it up when I had it. IIRC they scored lower numbers than Buschur in that test.

Buschur doesn't care about anything but going forward, either.

**Murlo26** · 05-26-2011

The one in that test was just two 255's I believe. He brought the bigger pump into the equation for the X because it has the same dual voltage setup as stock I thought. i could be wrong but who knows.

Regardless, I am always amazed at the new/different problems your fuels system has.

Eventually, everyone will be using your testing/knowledge to design X fuel systems, i applaud you.

**mlomker** · 05-26-2011

Quote:

Originally Posted by Murlo26

Eventually, everyone will be using your testing/knowledge to design X fuel systems, i applaud you.

I appreciate your positivity. As you can imagine, I find it hard to remain optimistic in times like this.

**Murlo26** · 05-26-2011

Trust me, I know what you mean...spending kilobucks on cars over and over gets old, I know.

Look on the bright side, through all this, you have always been able to drive your car.

**mlomker** · 05-27-2011

I was able to confirm that the hanger return is the problem. The one used thing that I buy (fuel hanger) and it has a problem. Go figure.

Now I'll have to find a source for that black slinky hose in the hanger for the return...they snap on so can only be used once. grr.

**Kracka** · 05-27-2011

Would a rubber fuel hose with hose clamps work?

**mlomker** · 05-27-2011

Quote:

Originally Posted by Kracka

Would a rubber fuel hose with hose clamps work?

I've heard from people that have tried and they say it invariably kinks up due to the angles. 30r10 isn't cheap either so if there's a source for a new plastic line then that'd be a better way. I have an email off to JRZ Tuning, who was able to get one for someone.

It isn't designed to be hose-clamped back on but I'll eyeball it when I cut it off.