IHs with 2ndry shorty injectors: More flow?

[LGAFF]

I had talked to a few people about 2ndry injector bosses......they mentioned that removed nearly the entire boss....on my siamese set I did the same and wow....plenty of meat for the injector.

So the next set I port....I leap before I look and do the same....and learned a hard lesson...however with error comes opportunity. There are shorty injectors out there and I have some on the way.

So that means more flow in the secondary injector runner.....we will see if it means any more HP.

[Jagdpanzer]

Lee,
Clue us in, which injector did you get?

[gbmidyear66]

I believe there is also some room to simply shim-up the fuel rail mounting - as opposed to a "shorty injector" - similarly allowing you be more aggressive in porting the secondary

[LGAFF]

They are custom LGAFF motorsports specials....;)

[LGAFF]

Let me check them out first and then I will post it up

[LGAFF]

http://i134.photobucket.com/albums/q115/lgaff/Picture109.jpg

http://i134.photobucket.com/albums/q115/lgaff/Picture108.jpg

[LGAFF]

I can take down the lead up to the boss opening even more to smooth things out

[XfireZ51]

I wonder if what you are not considering is the positioning of the injector nozzle relative to the valve head and aim of fuel stream into air flow. With the "shorty" injector, does fuel end up on wall of runner due fan pattern of spray? Some of what I have read suggests that fuel is aimed at valve head using the heat there to help atomize and vaporize fuel.

[LGAFF]

Actually most reviews I have read indicate better atomization with more travel.....the center of the inj does not change, so no it would not wash

[LGAFF]

This are not the first time these were used

[XfireZ51]

This are not the first time these were used


Not sure that validates anything. Not saying it invalidates anything either. By moving the nozzle further upstream and assuming the same angle of the spray from both injectors, the fuel will have travelled a longer distance from the nozzle of the shorty injector and so the fuel fan will have spread further out at the same point in the runner. The question is what is the effort worth?

[LGAFF]

Looking at some real-world examples, Strader reports that on a 1,000hp engine, the injectors were originally located 7 inches back from the valves. Doubling this distance to 14 inches was worth 50 hp on top


-Hot Rod Magazine

[LGAFF]

I am not sure what will result, just not sure why when the center of the nozzle does not change we arrive at a automatic loss in power.........

What I do know is that is a clear shot, air is not being forced downward by the boss....no loss in velocity no turbulance, etc


If removing the butterflies is worth 3-4 ponies, not sure how free flowing the air would not be the same....

[LGAFF]

Only injector nozzle no no is that do not put the injector more than 45 degrees to the wall

[LGAFF]

...and no I do not think the inj placement moving up 4-5mm is going to add 50hp....I think that point is not really relevant...I am looking at the opportunity to take full advantage of the 36mm 2ndry...think about the obstruction when it goes untouched or disrupts the total volume