stevieturbo

Perhaps should be in fuel section, but as most FI guys actually need more fuel, more users here might enjoy it.

http://www.superstreetonline.com/how...ootout-part-2/

The BallSS

iTrader: (9)

Good read Stevie.
I guess you really need to do the math to figure out which pump you need depending on application.
How does multiple pumps figure into this?
If you need 60 psi for proper injector function and are running 10 lbs. of boost how do you figure out if you need a single bigger pump or two smaller pumps?
I only asked because I maxed out my single 255 pump then added a second for additional fuel.

stevieturbo

Really just depends what is easiest for you.

A big single clearly has benefits. Less fittings, clips, hose, wiring, whatever and no real issues about failure. If it fails the engine stops.

Some do not like multiple pumps for those reasons. But multiple pumps are a cheap way of getting a lot of fuel flow and as long as it's done correctly is usually very reliable.

kingtal0n

iTrader: (1)

IMO use a safety pressure switch with a single or multiple cheap pumps for the majority of stock/turbo engine situations (500-700rwhp regions) You can do it with $300 in the tank reliably, silent either way. I am so sick of A1000s

I've seen a single "fail" but still run/idle the car before so not ruling this out as a matter of fact, not over a $6 pressure switch.

The BallSS

iTrader: (9)

I added an additional walbro 255 to my stock bucket.
It has its own harness, relay and fuse.
It's also on a 4 psi Hobbs switch so it only comes on at WOT.
The way I plumbed it in the bucket probably isn't ideal but with such limited space there wasn't much choice, that and others have laid down respectable numbers with identical setups.
I had looked into adding a single 340 but a good friend of mine who's been in the LS/FI game forever recommended adding a second pump for the sake of additional volume.

93camaro_zzz

iTrader: (13)

Good info!

wildcamaro

iTrader: (15)

Thanks for posting, Not enough real world testing out there...

stevieturbo

Certainly it's difficult to find any for public consumption if there is !!

93camaro_zzz

iTrader: (13)

Only thing they need is the 450 in that test.

AnotherWs6

iTrader: (17)

Somebody said recently something very interesting. If you are running dual pumps and one fails the one functioning pump will be enough for it to kee running but lean as S. And then... Don't know if I'm regurgitating well known knowledge, but it made a ton of sense to me.

stevieturbo

This is true...but you have to accept risks or compromises with any build. Or spend the money and apply safety features.

Whether that's some sort of crude implementation like king suggested, or inbuilt feature of a good aftermarket ecu...is entirely down to your budget.

customblackbird

iTrader: (2)

Can't believe they didn't test the aeromotive 340 stealth pump, the Holley, walbro and other name brand pumps. Seemed like they are only interested in the one aftermarket brand pump.

brandon6.0

iTrader: (32)

I run twin walbro 255s full time with my setup. I have them at 58 base psi with deka 80s. I saw were some of the pumps had safety valves for around 75psi. Now id i have lets say 16psi of boost on top of base 58psi on these walbros wouldnt the valve open?? Is there a way to modifie thw bypass valves??

rotary1307cc

iTrader: (5)

There is zero chance of hurting anything with a pump failure if you have the proper ECU. If my fuel pressure drops out of target on a MAP vs fuel pressure table the engine shuts down instantly

M_Minnick

iTrader: (1)

Here is some test data from some pumps that are more in line with what we are actually using.

http://www.kinsler.com/index.php/pumps/electric-pumps

I would like to see them tested at higher voltages. I plan on running a 14v system in my car, so system voltage will be at 16.8v with the car running. I'd like to see what dual 450's will put out at 70psi at that voltage. I would bet it's over 1000lph.

Mike

The BallSS

iTrader: (9)

Wouldn't that significantly affect the lifespan of the pumps though?

customblackbird

iTrader: (2)

The fuel pump motors supposidly aren't as suseptable to shorter lifespans due to higher voltage. Inadequate wiring and low voltage will kill a pump. Supposidly going from 13.2 to 16+ is a large bump in performance. However most of the pumps tested at 13.2v there flow is inaccurate as most working charging systems are putting out 14-14.4v and if your fuel pump wiring is good then your getting pretty much full voltage at the pump give or take .5v if u suck at making connections.

customblackbird

iTrader: (2)

interesting link. Much better than the first link as they tested a lot of the pumps out. Shocked by the output of the dual billet Holley dominator pump... Lower than I expected. Still no stealth pump but testing at 13.2v is not accurate given most systems run 14-14.4v.

stevieturbo

It's a very valid test, and reality is the voltage is probably quite true for most installs, given varying wiring, and alternator performance.

And IF...IF your setup does offer more voltage, then you've added safety in terms of pump ability. You're never on the wrong side.

customblackbird

iTrader: (2)

Sure it's a valid test, accuracy is close. Most people who run aftermarket high end pumps will upgrade the wiring for said pump. Just saying it's possible to see a full volt over what they tested on a normal 14.7v system. But I would agree that if your putting out more voltage it's a good thing. But I would still love to know what my 340 aeromotive stealth pump flows at 60-70psi with a full 14.4-14.7v.