Could someone point me in the right direction for selecting the proper size injectors?

BR 3065
Comp 272 cams
licp/uicp
ams ic
walbro 255
stock ecu

I figured there would be somthing about this in the "Evo Modding for Dummies" guide. Thanks in advance.

 

i would go with precision 880, i got a set for sale if you need them as well. But for me when I installed my cossi cams, my precision 780s my injdc was around 78% with a bigger turbo you'll want to go bigger.

 

This help me in picking mine. Scroll down to the fuel injector worksheet;
http://www.rceng.com/technical.aspx?...MvLf48nFpg42ra

These were my figures;
Actual desired crank horsepower: 350 (I ain't greedy)
Number of injectors; 4 (duh)
Brake specific fuel consumption desired; .65 (but try .60 too and see what comes out)
Maximum injector duty cycle; 80 percent (I play it safe)
System fuel pressure; 64 psi (43 psi idle pressure plus my 21 psi of boost at a 1:1 raising rate equals 64 psi.)
Hit the calculate button; 616cc injectors
Went to FIC and got me some 650cc injectors in 2005 and been happy ever since.

 

Check this calculator out. It doesn't use generic data, it's data specific to the output of the Injector Dynamics data. You'll find that with the right inputs, it's dead nuts.

BTW, when inputting fuel pressure data, you input the base pressure with the vacuum disconnected from the regulator, not the base pressure plus boost. The injector ends up firing into a pressurized manifold under boost, that's why the fuel pressure is increased to make up for it. You maintain the same flow through the injector as at idle.

http://www.injectordynamics.com/hors...alculator.html

 

All these calcs are good don't get me wrong but my question is this: What is it representing? My car is a daily driver on 93 it will occasionally see C17. The RC calc is more understandable for me, but does it mean bhp for 93 octane or for c17 or for 93 with water/meth or what.

Do I calculate for what the motor will see most often or what the max I plan to run on the motor. Does it take in account for water/meth or does that even matter?

There are alot of variables here that need to be addressed.

 

easiest thing is to call RC Engineering. They will ask the questions that need asking, and tell you the correct size that you need. This is especially good since they have been doing this for a LOOOONNNGGG time and there will not be a chance of a fudged number and having to buy another set of injectors.

 

I would say go bigger than you need in case you upgrade the turbo or decide to go on E85. 1000cc or 1200cc if you ask me. I'm no expert though, call buscher or AMS and see what they think.