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-   -   Twin external Bosch 044's over kill for 500RWHP?? (https://my350z.com/forum/forced-induction/534979-twin-external-bosch-044s-over-kill-for-500rwhp.html)

djtimodj Sep 8, 2011 01:05 AM

Twin external Bosch 044's over kill for 500RWHP??
 
Im looking to move from a single in tank walbro 255 to a swirl pot set up.

Im looking to use the 255 in tank to supply a 4L swirl pot and then run twin bosch external pumps + filters etc. to supply the fuel rails. Im using a AAM fuel return kit with billet rails etc. Twin 044 will supply all the fuel Ill ever need but Im unsure If it will over power the return line?

Any idea's?

Thanks.

midz350 Sep 8, 2011 02:02 AM

A DW 300LPH in-tank fuel pump will make 500whp all day on any dyno out there.

Cux350z Sep 8, 2011 03:10 AM

so if the twin boschs outrun the walbro filling the 4 liter tank where are you left?

deanfootlong Sep 8, 2011 05:41 AM


Originally Posted by Cux350z (Post 9359117)
so if the twin boschs outrun the walbro filling the 4 liter tank where are you left?



well, if you have the lines routed correctly, you wont outrun the 4L tank. 255 to the tank, 044's after feeding from the tank to the rails, then return line into the 4l tank with an overflow at the top of the 4l tank to the actual fuel cell return. that would work.

question; why is your expected whp amount set at 500? if its just a number you want to reach, you may even do it with a single 255 and this could just be overkill. however, i think this set up is a great idea if you are shooting for as high numbers as you can.

Cux350z Sep 8, 2011 06:22 AM

So you're saying you would over fill the 4l tank and have the excess fuel go back to the oem tank or use a sensor to shutoff the walbro feeding the 4l tank?

Cux350z Sep 8, 2011 06:23 AM

Oh and this idea sounds dumb for such a low power build.

Keep it simple, build it reliable and be done.

deanfootlong Sep 8, 2011 06:29 AM


Originally Posted by Cux350z (Post 9359326)
So you're saying you would over fill the 4l tank and have the excess fuel go back to the oem tank or use a sensor to shutoff the walbro feeding the 4l tank?

google "fuel surge tank" and you'll get a better understand of how these have been done. no need to have a sensor shut off the 255.

like i said, for 500whp, id pass on it. but you know that once you make 500 whp, you'll want more.

str8dum1 Sep 8, 2011 06:56 AM

no such thing as too much fuel pump.

I understand your desire for a surge tank. I would just use 1 pump after the tank though. Either a 340LPH hi flow or a big weldon/magnafuel/fuel labs.

That way if something happens to the pump, the car stops. It doesnt just run low fuel pressure and blow your motor.

psychoballistic Sep 8, 2011 07:23 AM


Originally Posted by str8dum1 (Post 9359384)
no such thing as too much fuel pump.

I understand your desire for a surge tank. I would just use 1 pump after the tank though. Either a 340LPH hi flow or a big weldon/magnafuel/fuel labs.

That way if something happens to the pump, the car stops. It doesnt just run low fuel pressure and blow your motor.

+1 I too am a firm believer in having a ton of potential fuel. One pump is a much better idea unless you have seaparately wired the pumps into your ems and the ems can trigger a safe mode or power cut to prevent damage if the auxillary pumps are not coming on.

This may be a stupid idea, but if your aiming in the neighborhood of 500whp, and many have completed this on a 255, why not consider one bosch 044 in the tank? I know that twin 044's won't fit, or would require alot of work, but if the goal is around 500, why not one 044 in the tank? Seems like alot of plumbing for something that can be done pretty simply.

If the goal is more power down the road, completely disregard what i'm saying and go the surge pump route.

deanfootlong Sep 8, 2011 07:36 AM


Originally Posted by psychoballistic (Post 9359435)
+1 I too am a firm believer in having a ton of potential fuel. One pump is a much better idea unless you have seaparately wired the pumps into your ems and the ems can trigger a safe mode or power cut to prevent damage if the auxillary pumps are not coming on.

This may be a stupid idea, but if your aiming in the neighborhood of 500whp, and many have completed this on a 255, why not consider one bosch 044 in the tank? I know that twin 044's won't fit, or would require alot of work, but if the goal is around 500, why not one 044 in the tank? Seems like alot of plumbing for something that can be done pretty simply.

If the goal is more power down the road, completely disregard what i'm saying and go the surge pump route.



because, correct me if im wrong, the 044 only flows roughly 300 lph. sounds like too much work for 45 extra lph. do they make a 044 that fits in the stock fuel pump assembly?

jerryd87 Sep 8, 2011 08:58 AM

im one of the ones that fully supports running a swirl pot, especially if you wanna take corners fast which is really what these set ups are for. one thing to note you will never need 4L save some hassel and get something smaller i think the one i had sasha build is roughly 1.5L and that should be enough to power 700hp for like 45 seconds(rough estimate cant remember the exact math.), your supposed to build them to provide enough fuel at max power for 15-30. If you want to set it up to be expandable then have a tank build with two outlets on the bottom and three on top. one on top will be the feed, one will be the return, and one will be the overflow. the bottom two have a 044 hooked up on one side then the other side cap off until you decide you want more power then put a second 044 in, and redo the lines up from there however is best for you. 4L will be a very large tank and you will have to look for a place to put it, if you put it inside use teflon lines to avoid the smell and remember you will need a firewall to be safe possibly a box of some sort.

psychoballistic Sep 8, 2011 09:18 AM


Originally Posted by deanfootlong (Post 9359460)
because, correct me if im wrong, the 044 only flows roughly 300 lph. sounds like too much work for 45 extra lph. do they make a 044 that fits in the stock fuel pump assembly?

I do not believe they make one that fits in the stock assembly, but in this case the work is just being re-allocated to more potential issues...

If all other parts remain the same, it really comes down to fitting the pump v.s all the other work here... six to one half a dozen I guess. I personally would try to find a way to fit a 044 in the basket by itself. I'm sure if someone wanted to get really creative they could talk to a machine shop or vendor on here and get something made/ fabricated to fit the 044 but in that case, why not just opt for a CJM twin pump then?

As for the 044 and its flow of ~300lph, that is plenty of fuel for a 500whp Z, especially when people are running 255's and making 500+ without issues.

meatbag Sep 8, 2011 09:55 AM

If you goal is 500whp, a single walbro will be more then enough.

When you look at pumps you have to look at what they flow at what pressure, flow at 0psi of pressure means jack ****. For this reason a bosch 044 still flows more then almost every other pump on the market.

Yes you can have too much fuel, especially in a return system because you can run into the problem of dumping too much heat into the fuel itself with running super high pressue and volume pumps at low levels.

deanfootlong Sep 8, 2011 10:07 AM


Originally Posted by psychoballistic (Post 9359673)
As for the 044 and its flow of ~300lph, that is plenty of fuel for a 500whp Z, especially when people are running 255's and making 500+ without issues.

my point exactly. waste of time.

you know anyone that makes 500 whp is probably prepared to make more. so why be limited. im all for the surge tank idea. is it overkill for 500whp, yes. but we all know you will get sick of that number very soon thereafter.

str8dum1 Sep 8, 2011 10:13 AM

horsepower is not the issue. its running an in-tank pump dry under high G cornering. How is it overkill for 5 or 500 whp if you still starve a pump for fuel???

any good hi flow external pump can be run on a controller so you dont run into the fuel heating problem. So no, there is no such thing as too much fuel pump. We arent talking about not doing the job properly.

deanfootlong Sep 8, 2011 10:23 AM

shouldnt be a problem making 500 whp with an in tank 255. maybe me saying it's overkill for 500whp was a bad word choice as im all for it. is it absolutely necessary, no.

ace32x Sep 8, 2011 10:29 AM


Originally Posted by midz350 (Post 9359107)
A DW 300LPH in-tank fuel pump will make 500whp all day on any dyno out there.

speaking of which i have one for sale ill let go cheap if u need one! used it for 100 miles then ended up switching to a twin pump set up so gotta move this 1! :D

Blackbird CPV35 Sep 8, 2011 10:52 AM

Seems like overkill, anyone ever try in tank foam?

http://www.evomx.com/fuel-tank-foam-information/

str8dum1 Sep 8, 2011 11:45 AM

you are still not understanding. he needs an external pump to run the surge tank. The surge tank is needed.
1 in tank pump is not an option with a surge tank. He will be fine with 1 external bosch.


I wouldnt mess with that foam on a saddle tank design. Maybe in a fuel cell when you dont have to worry about a siphon, etc


Originally Posted by deanfootlong (Post 9359791)
shouldnt be a problem making 500 whp with an in tank 255. maybe me saying it's overkill for 500whp was a bad word choice as im all for it. is it absolutely necessary, no.


deanfootlong Sep 8, 2011 12:04 PM


Originally Posted by str8dum1 (Post 9359935)
you are still not understanding. he needs an external pump to run the surge tank. The surge tank is needed.
1 in tank pump is not an option with a surge tank. He will be fine with 1 external bosch.

never stated he should use a surge tank with a single in tank pump only.


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