STALL UP

iTrader: (2)

I am about to install my second 255 intank and got to thinking about it. I have all the stuff to install it to a 4psi hobb switch that I was going to thread into the intercooler piping but I was wondering what would be the down side of just hot wiring both of them all the time. Would I have a problem with overheating the fuel? The car is just driven on pretty days around town and has -6an feed and stock feed as return w/ boost referenced FPR and nasty fuel rails. looking to support 700-800rwhp and was just thinking that with the hobb switch it would just be another thing to fail and cause problems later on. thanks phill

MIGHTYMOUSE

iTrader: (59)

cycling fuel around the engine continuously can increase the chance of vapor lock and cavitation at the pumps. There really is no reason TO leave both on if you have the ability to trigger a reliably operating pump. There is also the potential that you will run into a fuel pressure problem at idle and high vacuum situations (where it will not go low enough).

vandal0-0

iTrader: (3)

I was wondering the samething.I was useing a hobb switch for the second pump and the switch failed.So I talked to a friend that works at a shop on high horsepower supras and they run two pumps at the same time and run a third on a switch.So I hot wired both of mine with seperate harnesses.I havent had a problem but the car is hardly driven.How else could you activate the second pump.

MIGHTYMOUSE

iTrader: (59)

sux for the switch to fail, i use an led to indicate to me when the pump is on.

i have used an tps trigger from my bs3 box as well as a boost trigger from my e-boost controller and both have been completely reliable.

code4

iTrader: (30)

I have run both my pumps full time for around 5k miles without any problems. I like the idea of less switches, wires, relays etc. on my car.

vandal0-0

iTrader: (3)

I was thinking of a rpm activaied switch with a wide open microswitch like what you would use for a nitrous system.

Hennytime

iTrader: (33)

if you were to wire two pumps, wil the reacetronix wiring harness be enough to power both? I was also reading in the other thread you started mm about hte cheap and easy dp setup, but that wasnt really answered in there. great write up too

code4

iTrader: (30)

I am using a single racetronix hotwire for my 2 walbro set up. It has worked fine but racetronix said that was a no no. They recommend 2 hot wire kits.

Hennytime

iTrader: (33)

ill watch for when your car burns JK JK, seriously hope it works out

STALL UP

iTrader: (2)

I was going to run an LED like MM said he has but it is hard enuff to watch the boost/ fuel pressure/ wideband/rpm and the road and to add anotherthing in there is getting like trying to fly a plane and I am just concerned with the hobb switch not being reliable.

MIGHTYMOUSE

iTrader: (59)

the light is either on or off, if you dont see a light out of the corner of your eye, let off.

hobbs switches like the ones nos uses are high quality and reliable... thats why they use the type they use

STALL UP

iTrader: (2)

that is the type of switch I got from napa. I am still deciding on what to do thanks for all yalls help

Inspector12

iTrader: (29)

I run it both ways on the black car it has a hobbs switch and the orange car I run both all the time I haven't had a problem on either. I did find that the orange car's fuel presure was a little more stable I don't know if the regulator is not reacting as quickly or what, but either way it was able to be tuned around.

Frost

iTrader: (45)

They said it's a no-no because the harness is designed to fully support ONE of their pumps and you are running it into TWO. The voltage drop across it will cause higher than normal current in the pumps which can cause excessive heat in the pumps, also the added current will wear out the the brushes in the motors faster, and the the current demand on the cable will be higher than 2x it's intended design from the voltage drop as well, meaning areas like connectors will see higher current than designed for alsowhich leaves them as potential failure points in the future.

It's a crappy shortcut to take to keep from running one extra wire.

MIGHTYMOUSE

iTrader: (59)

honestly though 10GA is overdoing it for a single pump, its not a crisis situation, but the math definitely says the pump will run faster the more voltage that gets to it.

BOTTLEFEDLS1Z

iTrader: (32)

How did you wire a LED to indicate when the second pump is on?

MIGHTYMOUSE

iTrader: (59)

the trigger wire goes hot when my tps criteria is met for the second pump. this power trips and holds the relay closed feeding power to my pump. T power off of that trigger wire to the led and ground the other wire of the led.

when the relay is being triggered your led will be lit. i also look for the fuel pressure to jump.

if your trigger wire is a ground, you can do the same thing, just give the other leg of the led switched power.

ss1

iTrader: (32)

So it tells you when there is power to the pump, but not if the pump is actually working?

I think some people may assume if the light is on, the pump is on.

MIGHTYMOUSE

iTrader: (59)

even if you used power right off the pump wire. it is an assumption that when it has power, it is working.

end all be all is watch your fuel pressure like good boys and girls. there is no pump output speed sensor or that type of thing.

code4

iTrader: (30)

Oh I think I'll be alright, I've ran a lot more than that on a 10 guage wire. I think they were more worried about the relay. I have ran the **** out of it for 5k miles, wire has never got warm. If I was worried about wire size I would run some 8 guage instead of 2 wires.