PDA

View Full Version : Think I need a 2nd fuel pump?


Flash68
04-29-2009, 08:57 PM
So I got around to thinking about my fuel system again as we are about ready to fire up the motor for the first time in 2+ years. I originally had the A1000 external pump with the stock tank, but switched it out for a nice Rick's tank with in-tank Bosch pump. I never really checked the specs on the pump until now and I have a few questions/concerns.

I have the 044 pump per Hector at Rick's, but I just noticed it is rated up to 685-700 hp. I am now concerned since my motor already dyno'd at 700 REAR WHEEL hp.

Will I be running at the dangerous edge of not enuf fuel here? I know a lack of fuel is not a good thing for a forced induction motor.

I am thinking it might be a good idea to add a second 044 pump inline between the tank and the fuel rails.

Thoughts?

lil427z
04-29-2009, 09:03 PM
weldon pumps.
rick k

Spiffav8
04-29-2009, 09:09 PM
700 REAR WHEEL hp! :wow:

When and where do I show up for a ride!?

Flash68
04-29-2009, 09:19 PM
weldon pumps.
rick k

Are you saying to add a Weldon inline pump to the system? At this point I do not see us taking apart the Rick's tank and switching out a perfectly good 044 pump.

700 REAR WHEEL hp! :wow:

When and where do I show up for a ride!?

That's what a Jody Bernard-built monster puts out... on 91 octane. :)

I would love to make a trip to Vegas in this car sometime. :unibrow:

Spiffav8
04-29-2009, 09:23 PM
That's what a Jody Bernard-built monster puts out... on 91 octane. :)

I would love to make a trip to Vegas in this car sometime. :unibrow:

Well you've got a place to stay and a garage to park the car in any time you want it.

camcojb
04-29-2009, 09:31 PM
you'll know if the pump is an issue as the fuel pressure will drop during a wot run (assuming injector duty cycle is good). Injector duty cycle will tell you if the injector is too small if the duty cycle starts approaching 85-90%+. The injectors in that motor (75's I believe) with an A1000 Aeromotive pump were perfectly safe. You may need another or additional pump at the 700 rwhp level, but I thought you had dropped the boost back with the larger blower pulley............ :yes:

Jody

Flash68
04-29-2009, 09:44 PM
Well you've got a place to stay and a garage to park the car in any time you want it.

Thanks Curtis. I hope to take you up on that offer someday my friend. :thumbsup:

you'll know if the pump is an issue as the fuel pressure will drop during a wot run (assuming injector duty cycle is good). Injector duty cycle will tell you if the injector is too small if the duty cycle starts approaching 85-90%+. The injectors in that motor (75's I believe) with an A1000 Aeromotive pump were perfectly safe. You may need another or additional pump at the 700 rwhp level, but I thought you had dropped the boost back with the larger blower pulley............ :yes:

Jody

Yep it has the RC 75#ers... and I never thought to check the capacity of this 044 pump til lately. Guess it's simple to add a 2nd inline pump if necessary.

Jason had told me he wanted to start me out at larger pulley/lower boost, but we will be losing some boost with the addition of the IC anyway all other things being equal. He wants me to get used to the car first at lower boost, which I can appreciate. I dunno, I will see if I can talk him into the smaller pulley. At least we can test how far we can push this system on a single pump I guess....

camcojb
04-29-2009, 09:46 PM
Thanks Curtis. I hope to take you up on that offer someday my friend. :thumbsup:



Yep it has the RC 75#ers... and I never thought to check the capacity of this 044 pump til lately. Guess it's simple to add a 2nd inline pump if necessary.

Jason had told me he wanted to start me out at larger pulley/lower boost, but we will be losing some boost with the addition of the IC anyway all other things being equal. He wants me to get used to the car first at lower boost, which I can appreciate. I dunno, I will see if I can talk him into the smaller pulley. At least we can test how far we can push this system on a single pump I guess....


just keep an eye on the a/f, duty cycle, and fuel pressure.

Jody

Flash68
04-29-2009, 09:49 PM
just keep an eye on the a/f, duty cycle, and fuel pressure.

Jody

will do!

gearheadgarage
04-29-2009, 09:55 PM
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. :lateral:

Flash68
04-29-2009, 10:02 PM
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. :lateral:

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. :D

Isn't Lateral G the greatest! :thumbsup: :lateral:

LS1NOVA
05-01-2009, 04:43 AM
It would be better to add a additional intank pump instead of an inline.

Flash68
05-01-2009, 09:43 AM
It would be better to add a additional intank pump instead of an inline.

Why is this better?

Flash68
05-01-2009, 03:03 PM
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
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
05-03-2009, 12:23 PM
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
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
05-03-2009, 03:33 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!


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
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
05-03-2009, 11:53 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!

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..

-----------------------------
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.
--------------------------------

Flash68
05-04-2009, 12:00 AM
After reading this info on the 044, I am even a little more worried....

http://www.tweakit.net/shop/product_info.php?currency=USD&products_id=369&utm_source=froogle&utm_medium=feed

-------------------------------
Bosch "044" Motorsport fuel pump is our most popular high performance fuel pump. With reliability that the big German company is known for, it's our #1 choice in our workshop here. For upto 730HP at the flywheel or use two pumps for upto 1200HP on turbocharged applications.

As performance levels increase via greater airflow efficiency or higher boost levels, fuel delivery is crucial in developing maximum horsepower and in maintaining proper air/fuel ratios.

The Bosch In-line Fuel Pump upgrade replaces the factory pump to maximize flow for high boost applications where the factory injector pulse duration is substantially increased or where additional or larger injectors are utilized.

* Recommended for Turbo/Supercharged engines upto 600HP.
* Recommended for Naturally Aspirated engines upto 730HP.
* Flow Qty litres/hour (pressure): 200 (5 Bar)
* Inlet Connection: M18x1.5
* Outlet Connection: M12x1.5
* Length (mm): 196
* Diameter (mm): 60
* Max Power Consumption (Amps): 15.5
* Electrical Connection (-/+): M5/M6
* Methanol Tolerant

Our Bosch pumps are the genuine item and come sealed in their original Bosch yellow box.