what injectors would be good?

[cody92talon]

i have a fully built motor and was looking at putting a hx 40 on my set up. Rite now i already have a set of pte 880 injectors. Are these going to be big enough?? My goal is about 400hp rite now because im still sporting fwd!!

 

[GRAVEDIGGER]

Those 880's will be enough to support your goal of 400hp.

 

[crazyquik22023]

ya 880's will be plenty. you might wanna upgrade to a 255lph fuel pump though

 

[cody92talon]

i have a walbro 190 in right now will that be enough? Or do i have to go with a 255?

 

[skatershawn]

Id say if you rewire the 190 you might be good!
But the hx40 pushes some massive amount of air!
What boost level are you planing on running?

Man theres a thread on how much lb/min will start out running a select amount of test fuel pumps but i cant find it anywhere right now!

It would help you right now to figure if you need to get a 255 or not!
Personal i would... but i do think a rewire on the 190 my suffice for now!

If i find it ill link you to it inless someone else beats me too it!

 

[jeffo]

Even a rewired Walbro 190lph isn't going to make 400 whp. For 400whp you are going to need to be running at least 25psi, which would make your fuel pressure 37psi + 25psi = 62psi. At 62psi a rewired 190lph is only going to be able to supply ~145 liters/hour of fuel. That's only 604cc/minute per injector.

 

[JayRolla]

Its not worth the risk of running lean at wot just to see if the 190lph will do it. Upgrade that first. The injectors should handle 400whp but you wont beable to max the turbo on those injectors.

 

[rEclipserGST]

Even a rewired Walbro 190lph isn't going to make 400 whp. For 400whp you are going to need to be running at least 25psi, which would make your fuel pressure 37psi + 25psi = 62psi. At 62psi a rewired 190lph is only going to be able to supply ~145 liters/hour of fuel. That's only 604cc/minute per injector.

I thought a Walbro 190 was suppose to put out 190 liters/hour?

Why don't you do that math again but with 43 psi at the fuel rail. For us 2g guys. I would do it myself, but I can't figure out an equation that works.

 

[cody92talon]

i forgot to list earlier that i do have the 190 rewired.

 

[NemesisTalon88]

sooo this on pump fuel right? the 190lph should be okay...kinda risky i would just go with a 255lph just to be safe i mean you can always take away fuel if you run to rich...

 

[cody92talon]

yea this is on pump fuel. ok thanks for the help guys!!

 

[GSTTOBEAT]

I would say be on the safe side and get a 255.

 

[jeffo]

I thought a Walbro 190 was suppose to put out 190 liters/hour?

The output volume of fuelpumps is rated at a very low flow pressure, which doesn't do us much good when our fuel pressure rises 1:1 with boost. According to this page, the "190" pump gets its rating from 190lph at 0psi and 12 volts!
Auto Performance Engineering - Walbro fuel pumps specs
0psi is just free flowing into a container, no pressure!
Even a rewired 190lph pump only flows 190lph (50 gallons/hour) at 40-45psi. On a 1G that's 37psi base fuel pressure and only 3-8psi boost. On a 2G that's 43psi base pressure + less than 2psi boost. As boost rises, the total pressure the fuelpump must provide rises 1:1, and the volume drops quickly.
RRE Instructions

Why don't you do that math again but with 43 psi at the fuel rail. For us 2g guys. I would do it myself, but I can't figure out an equation that works.

The problem is even worse for 2G guys, because you are starting out at 6psi higher base fuel pressure. 43psi base fuel pressure + 25psi boost for 400HP would be 68psi. Even rewired, a 190lph pump at 68 psi is probably only going to be flowing ~135lph, which is only 562cc per injector per minute. IMO, you should never have injectors that are capable of outflowing your fuelpump, it should be the other way around if possible. Its just not worth the danger of leaning out.

 

[awd_tsi91]

def get a 255! would be benificial i many ways like stated!

 

[cody92talon]

ok guys thanks ! will do