Think I need a 2nd fuel pump? - Page 2 - Lateral-g Forums

**Flash68** · #11 04-29-2009, 10:02 PM

Quote:

Originally Posted by gearheadgarage

If you're not afraid of more boost, neither am I. Let's get it dialed in, maybe pre-dyno with a couple test runs and some shakedown miles. The beauty of an injected car is, as Jody states, that we can study fuel trims & duty cycle to know if we're dangerous & lean before it's too late.

No motor likes to lean out. Lean burn is one of the worst things that any motor, especially a heavily Supercharged motor, can suffer from. Once we do our preliminary fire-up, we can gather some readings and map out a plan. At this point, we can rely on the 02 sensor and a tailpipe sniffer on test runs up & down the sweet stretch in front of the shop to get a feel.

If anyone has any thoughts, suggestions or objections feel free to chime in. Theory is all good, but experience is definitely not to be ignored.

Sounds like a plan. You guys know your stuff - I am just trying to catch up and learn more.

And you do have some nice frontage road there by your shop.

Isn't Lateral G the greatest!

LS1NOVA · #12 05-01-2009, 04:43 AM

It would be better to add a additional intank pump instead of an inline.

**Flash68** · #13 05-01-2009, 09:43 AM

Quote:

Originally Posted by LS1NOVA

It would be better to add a additional intank pump instead of an inline.

Why is this better?

**Flash68** · #14 05-01-2009, 03:03 PM

Quote:

Originally Posted by Sparky67

Another option is to contact Hector at Rick's Stainless Tanks and see if they can modify your tank to add in another 044 fuel pump. I am having Rick's build me a fuel tank with twin Bosch 044 fuel pumps now for my Harrop supercharged LS3 67 Camaro.

Jeff

http://www.kodakgallery.com/67rscamaro

It is an option indeed, but I'd rather not yank the tank and send it back to them to tear open. I should have thought of this beforehand (obviously!) but I am hoping an inline 044 pump will suffice. I know many of the 996 Turbo guys who get to 650+ hp add an second inline 044 pump so I don't know why it would not be okay here....

Is there a reason 2 in-tank pumps is better than 1 in-tank and 1 inline?

You have a sweet project there Jeff!

**WSSix** · #15 05-03-2009, 08:12 AM

Because with two in tank pumps the two pumps are pulling through separate lines. Adding an inline pump means it is pulling fuel through the other pump or simply boosting the fuel the other pump is supplying. It works but at the level you've built the car two, two in tank pumps is smarter.

Jody and gearheadsgarage are correct though, just take it easy at first and pay attention to the data log to know where your fuel is at. Data logging is real time so you can easily let off the throttle if it starts to go too lean and not hurt anything.

Check with Rick's and Racetronix. I think Racetronix had a setup that puts two intake pumps through the same sending unit. I know I've seen this setup somewhere. Essentially, it could allow you to simply drop a twin pump setup into your current tank and not modify anything major.

Oh and always remember that pressure is separate from flow volume. This is with any fluid and air is a fluid.

**Flash68** · #16 05-03-2009, 12:23 PM

Quote:

Originally Posted by WSSix

Because with two in tank pumps the two pumps are pulling through separate lines. Adding an inline pump means it is pulling fuel through the other pump or simply boosting the fuel the other pump is supplying. It works but at the level you've built the car two, two in tank pumps is smarter.

Jody and gearheadsgarage are correct though, just take it easy at first and pay attention to the data log to know where your fuel is at. Data logging is real time so you can easily let off the throttle if it starts to go too lean and not hurt anything.

Check with Rick's and Racetronix. I think Racetronix had a setup that puts two intake pumps through the same sending unit. I know I've seen this setup somewhere. Essentially, it could allow you to simply drop a twin pump setup into your current tank and not modify anything major.

Oh and always remember that pressure is separate from flow volume. This is with any fluid and air is a fluid.

Thank you, Trey. Great information.

tt69camaro · #17 05-03-2009, 03:10 PM

You could run a inline pump (A1000) just make sure it has its own feed line going to it. Don't tap into your existing line. If it were me I would just use one pump big enough to supply your HP needs. I use -12 to feed my pump with a -10 to feed the rails and a -8 return for my high HP stuff. I could go one step further and suggest a mechanical pump but your not making that much power. A mechanical pump is what I use now but I'm making 1776rwhp on 93 octane.
I may be new to this site but I'm not new to the game! Good luck!

**Flash68** · #18 05-03-2009, 03:33 PM

Quote:

Originally Posted by tt69camaro

You could run a inline pump (A1000) just make sure it has its own feed line going to it. Don't tap into your existing line. If it were me I would just use one pump big enough to supply your HP needs. I use -12 to feed my pump with a -10 to feed the rails and a -8 return for my high HP stuff. I could go one step further and suggest a mechanical pump but your not making that much power. A mechanical pump is what I use now but I'm making 1776rwhp on 93 octane.
I may be new to this site but I'm not new to the game! Good luck!

Yeah in hindsight I wish I would have went with the A1000 in-tank. I blew that one. Ha.

If we see we are running lean with the single pump I will have to decide whether to pull the tank out or just add a 2nd one inline.....

thanks for posting.

tt69camaro · #19 05-03-2009, 11:17 PM

Why take a chance of leaning out? I don't know much about your intank pump but was it rated 700 at N/A bsfc(.55) or forced inducted bsfc(.45)? I'm assuming you have an adjustable fuel regulator with boost reference?
I have a walbro intank pump that I thought supported the most HP of any small bosch type pumps (255 Litres) and it will only support approx 600fwhp forced inducted.
Anyway, You do what you want but its alot cheaper to do it right the first time. Good luck
BTW: Nice car!

**Flash68** · #20 05-03-2009, 11:53 PM

Quote:

Originally Posted by tt69camaro

Why take a chance of leaning out? I don't know much about your intank pump but was it rated 700 at N/A bsfc(.55) or forced inducted bsfc(.45)? I'm assuming you have an adjustable fuel regulator with boost reference?
I have a walbro intank pump that I thought supported the most HP of any small bosch type pumps (255 Litres) and it will only support approx 600fwhp forced inducted.
Anyway, You do what you want but its alot cheaper to do it right the first time. Good luck
BTW: Nice car!

Thanks man!

Here are the details of the Bosch 044, and it even references the popular Walbro 255 pump specs. This even recommends installing inline so maybe that is the ticket for where I am now. I kinda agree about being safe and adding it, since I know I will be cranking up the boost sooner or later..

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This is the popular Bosch Motorsports "044" fuel pump, as used by Japanese European & Australian tuner shops, JGTC cars, Touring cars, almost all WRC cars, and many more. Quite possibly, the most popular aftermarket fuel pump. Capable of providing 300 LPH free flow and 200 LPH at 5 bar (or 72.5 psi) for up to 685 BHP. In comparison, the Walbro GSS341 255 "high pressure" fuel pump can support 390 BHP Note: Values calculated at 12V, 3 bar (43.5 psi) base fuel pressure, 2 bar (29 psi) boost pressure, 1:1 fuel pressure regulator ratio. These are inline fuel pumps, we recommend they be installed between the factory (or another aftermarket) in-tank fuel pump, and the fuel rail. These may be installed in the fuel tank, but some custom fabrication will usually be required. In addition, feeding these inline pumps with another pump (in series), will boost the output of the Bosch 044 fuel pump even higher.
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