Staged Triple pump system ??

[da2k17]

OK guys I have a question about my fuel system. Here's my issue: when I drive the car for an extended period of time I get a terrible fuel smell in the car, its very bad. Its discussed in this thread http://www.svtperformance.com/forum...once-car-is-fully-warmed-and-driven-emissions

Since I'm running three Wallbro gss342 pumps in my return system I'm thinking if I stage them I can hopefully reduce some of the heat Thats causing this obnoxious odor.

My question is can I run one pump full time and put the other two on a Hobbs switch? Will one pump support casual driving?

Honestly I don't drive the car much at all, and when I do I don't beat on it at all anymore. So if I can reduce the heat from using three pumps that would make it a lot better when I'm out driving. My girl won't even get in the car anymore cause the smell of gas would get so strong she thought we were going to explode.

I always thought I had a fuel leak and I spent a lot of time going over the system trying to figure out why the smell would get so strong, it turns out the evap system just can't handle the amount of fumes generated from the heat that three large pumps create with the addition of the constant sloshing of the fuel in the tank.

 

[cj428mach]

One pump will handle it just fine. I'm running on one pump until the hobbs switch kicks in the second.

 

[da2k17]

That's what I'm hoping for. I'm also hoping I don't have to adjust the regulator. any idea if the regulator will keep the same pressure as its set for now when I shut the other two pumps off?

 

[cj428mach]

It should stay the same. The regulators job it to maintain your pressure so by lowering the volume you're sending to it the regulator should just send less back to the tank.

 

[TXEnginerd]

My regulator level drops about 2psi when I disable one of my two 465s. The same thing also happened when I had two GSS342s. I'm not sure if that's because it's a cheap regulator or what, but I now have my 465s staged. I just set my base 40psi with one pump off and accommodate for the bump up in fuel pressure in my tuning since it did richen up a bit at WOT.

 

[svtshadow]

I tried the whole staged pumps this, hobbs switch, that and still had hot fuel issues. So now I will do it right and call it a day, a fuel cooling system.

 

[TXEnginerd]

I tried the whole staged pumps this, hobbs switch, that and still had hot fuel issues. So now I will do it right and call it a day, a fuel cooling system.

I think I am having the same problem...

I have two 465s and the fuel lines would start to cavitate after only 10 minutes of running even with an almost full tank. Caused pressure to drop a bit.

Since staging the pumps it takes a lot longer to get to that point but it still happens. I had it in the back of my mind that my next step would be to add a small in-line cooler after the regulator and stick it in the grill area.

Something like this:
http://www.amazon.com/dp/B000CNHG7A...UTF8&colid=GIX4DWV1UI6Q&coliid=I1EM8RMOFGYR4Y

Have you done something similar or plan to? And what pumps and fuel are you running?

 

[gabe1530]

TXenginered, are you guys running sumped tanks? ive heard of people having issues similar to this simply because of the sump.

 

[badcobra]

I think I am having the same problem...

I have two 465s and the fuel lines would start to cavitate after only 10 minutes of running even with an almost full tank. Caused pressure to drop a bit.

What do you mean your lines 'cavitate'? Are you saying you can see your braided fuel hose bubbling?

And FWIW, I don't see how running pumps on a hobbs switch is going to change the way fuel smells in the car. Need better hose for that problem to go away.

 

[TXEnginerd]

TXenginered, are you guys running sumped tanks? ive heard of people having issues similar to this simply because of the sump.

Well, I'm running the stock tank which is sumped from the factory with a divisionx dual hat and 2 Walbro 465s. I do not have an aftermarket sumped tank though if that's what you're asking.

What do you mean your lines 'cavitate'? Are you saying you can see your braided fuel hose bubbling?

Meaning I can hear (what sounds like) air in the lines with the pumps on and engine off. Here's the video I posted in my own thread when I first encountered this:
[video=youtube_share;OWIklgeepIY]http://youtu.be/OWIklgeepIY[/video]

 

[cobra9903]

Mine made that sound when I opened the lines to replace filter fitting on a 10 feed line and once I let the pumps cycle for a couple seconds to get the air out it hasn't done it since. Wonder how it would be getting air in the lines?

 

[svtshadow]

TXenginered, are you guys running sumped tanks? ive heard of people having issues similar to this simply because of the sump.

Happens with stock tanks too.

 

[speeddemon2000]

This is how I ran mine:



It setup with the regulator before the rails so no fuel is circulated through the fuel rails limiting the amount of time fuel is in the engine bay. I also use a hobs switch on the second pump. On the fuel smell you need PTFE lined fuel lines. You may find this interesting. I am using the fragola push-lite 8000 series hose and they smell. Interesting enough though when I use e-85 the smell goes away.

You can see more details in this post: http://www.svtperformance.com/forums/showthread.php?979317-Return-Guys-Fuel-Pressure-Drop-when-hot

 

[da2k17]

got my hobbs switch today so hopefully ill get it installed over the weekend.

for the guys saying that it wont help the smell, you dont understand whats taking place. the little gas odor i would get in my garage from the lines isnt the issue. i built an open air garage for the car lol. the smell im getting while driving is like putting your face next to the nozzle when filing up your car. its so strong it burns my eyes, thats what im trying to get rid of. if i dont heat the fuel up as much and cut down on the volume sloshing back into the tank in theory it will make less pressure and fumes and hopefully the evap system will handle it. if not ill add a cooler. either way i need to do something.