interesting.

at cruise, the injector really would not matter as far as flow, but what about at WOT? is that where the 009 would flow more fuel than the US version? after all for a given amount of air coming into the engine it would only require the same amount of fuel no matter what injector was being used.

also, would the injector really need to be "matched" to the fuel head? the euro head has a lower system pressure than the aluminum US head so then the need for the lower opening pressure for the 009? which i thought goes with the euro head.

are you looking at the opening pressure as the flow rate? (3.7-3.5) little confused on your flow rates.

If you search the thousands of posts on fueling issues with modified engines you won't find one where the injectors were the limiting factor. For our street engines it just isn't an issue.
Matching the injector with the fuel system (not just the FD) is akin to the slightly different warm up times and pressures on the various WUR's. It is an optimization for the operating conditions of the engine type number.

Thanks to Helio for the specific tips. I'm running a GT35r twin scroll at 1 bar with twin wastegates, 964 cams, and a Garretson intercooler. The fuel head has been maxed out by CIS Flowtech and the WUR has been adjusted by them as well. I have a second WUR with Brian Leask to be made adjustable.

Thanks also to SpeedyS for the specific injector data, that was helpful.

Tonger

So can you tell us where you are at on your tuning ? Have you installed the euro fuel lines and injectors ? do you have an AFR gauge installed yet ?

I just got a set of the Euro lines and they are much bigger than the US lines.

Outer diameter: 6 mm Euro, 4 mm US
Inner diameter: 2.75 mm Euro, 2 mm US

I don't know how to upload the pictures but the difference is quite striking. With the resistance decreasing as a function of the radius to the 4th power, the Euro lines have about 1/3 of the resistance to flow that the US lines have.

Resistance to flow is proportional to (viscosity of fluid*length of tube)/radius^4 by Poiseuille's Equation.

Therefore the radius of the US lines are 1mm and the radius of the Euro lines is 1.375.

1 to the fourth power is 1 while 1.375 to the fourth power is 3.57. Using this as the denominator in the equation there is 3.57 less resistance to flow in the Euro lines compared to the US lines.

I am still waiting on my 009 injectors to arrive and have the Bosch 044 pumps waiting for me to construct the wiring harness from the relays and fuses that I got from Chris at Turbokraft. At Chris' suggestion I am going to run all new wiring on dual circuits/relays to eliminate any potential supply issues.

My AFR gauge has been in since the motor went in. I went with the WEGO IV on Al's suggestion and have been very pleased with it.