In series or parallel?

 

someone who has the setup can correct me if im wrong but the stock pump feeding the 044 and then to rails ive seen ona few cars but according to your data up there it would seem kinda well pointless.

it would seem in parallel would be the only way to be correct.

now there are two different flow rates for 044 pumps do you ahve the lower or high in that data above?>

 

AMS, great info as usual; what injectors do you recommend for e85 if one were to utiizile the stock oem pump....? I was thinking 1kcc PTE's?

 

Why not use a fuel pressure switch which kills the motor when fuel pressure drops below a preset pressure? Not unlike what we use with our nitrous setup.

 

thats a good point chad , is this plausable ?

 

We use these pressure switches which kill the nitrous if the fuel pressure drops below a certain preset pressure. I don't see why the same switch/s could not be used to shut down the spark/ignition.

 

That's actually a really good idea.

 

It could be done but you'd have to have conditions, you just can't kill ignition below a certain fuel pressure obviously otherwise you couldn't drive the car since fuel pressure drastically dependent on manifold pressure. You'd have to build a circuit that would take a few inputs, for example two hobb switches, one on boost pressure and one on fuel pressure. If boost is greater than 10psi and fuel pressure is less than 50psi for example you could have it do something.

 

I was not suggesting how to build it. I was saying it could be done. The concern seemed to be the costs of losing a motor if you used two pumps and on pump failed. Simply pointing those interested to a possible fix that no one seemed to be giving consideration to.

When using nitrous we have to improvise several safe guards that will shutoff the nitrous. The fuel pressure shutoff valve is one. Others are full engaugement of the clutch along with minimum and maximum rpm activations and shutoffs.

Just my two cents.

 

Ok, Todd returned my e-mail and he said the piggy back set up goes lean at 780 whp on his dyno, I need to run dual pumps in parallel. with an adjustable reg set at 4.2 bar. I am going to try to come up with some kind of fuel pressure safety switch. Thanks every one for all the input, Greg

 

Totally understand, I was just trying to give an idea of how to build something like that. Good idea!

-Martin

 

Ditto, I had one go out on my Procharged mustang and under a pass and i didn't lift fast enough...

 

running pumps in series reduces the flow drop as the fuel pressure goes up. The 996tt and Bosch 044 both have little flow drop relative to pressure but from previous tests I'd say the pumps would gain 30-50 lph at 90-100psi if run in series. Parallel would be much better. Two Bosch 044 in parallel flow 550 lph at 80psi for reference, good for about 1400whp.

I wasn't aware there are two different 044 pumps. I'm not sure which 044 I tested, I'd assume the higher one.

-Martin

 

One issue I ran into running dual parallel pumps on my Supra was too much flow at low RPM - I would overrun the return line and see raised pressure at idle and low revs. As soon as the RPMs went up the pressure was again regulated by the FPR and it would run fine. Drove me CRAZY tracking this down! The weird part was that it didn't do it when the pumps were first installed but began after they broke in - this was dual Walbro 255LPH HP pumps. To solve it I used an output on my ECU to turn on the second pump once RPM and TPS were high enough. I also used a pressure switch on the meth injection such that if I didn't see pressure in the line the boost target remained low and safe. The Aeromotive, Paxton, and other "coffee grinder" pumps never did it for me, like others I have seen a bunch of DEAD ones. I prefer the OEM style if flow and power used (!) can be sized right. People used to rave about Supra pumps but look at the power draw! Walbro 255 were much better, especially paired. Pay attention to the electrical draw and wiring, makes a huge difference..

An RPM switch and pressure switch together might work to protect against a single pump failure maybe?

 

Is the stock pump comparable flow-wise to an 044? (I always thought it was slightly different for packaging purposes)