DIY: Modify K-Series Injectors to flow 490cc and 520cc

[Mikey]

Here is a cheaper alternative to actually buying RC or any aftermarket injectors. Please note that these can be done to any set of K-series injectors from a k20 or k24. I have been doing this for a while just never told anyone. Apparently chunky from k20a.org has also been doing it and posted his results. So i thought what the hell might as well make the DIY so that way everyone else can start at it. So to make a long story short there are others that have been doing this for a while including myself so i aint taking credit for it. Got it.. good.. lol..

Here is how it goes:

-a set of 270cc injectors will typically flow from 480-490cc after modifications
-a set of 310cc injectors will typically flow from 510-520cc after modifications


Now lets get started shall we.



The injector on the left is a stock one, the one in the middle has had the plastic nose piece and O-rings removed, and the one on the right has had the wafer ground off. Typically you can use a belt grinder, dremel, nail file?? (lol), or anything that can grind away metal. Do not use anything with a very COARSE grit. Something a little on the finer side will suffice. So before we begin the grinding you need to remove the plastic piece and rings FIRST. Also note this: Be REALLY REALLY careful when pulling off the plastic nose piece cause you can break the lip around it and you will compromise the seal when you put the injectors back in.

Grind away little by little by little around the edges of the waffle and monitor the grind as to not grind away at the middle of the nozzle. Carefully monitor the progress until you could pry it off with a razor blade so you can see the middle hole.



Heres what it looks like before and after it is removed. A closer look






Heres another look courtesy of "chunky" from k20a






Again this pic is from "chunky" and i dont know if this is the same step he does.. but after i get done with grinding of the waffer out. I take something that is even finer than the grinder i used and fine sand it down so the metal is not as rough. You dont have to do it but do it jus to make it look pretty.





The last step is to tap the plastic nose piece back on (I use a small rubber hammer) and reinstall the O-rings.


It's critical that you don't go crazy with material removal when you're doing this because the little ridge just behind the wafer is what holds the nose piece on. If you grind or file that part down to nothing you're screwed as far as keeping everything intact and as it was to begin with, other than the intended removal of the wafer of course. This is pretty simple stuff, so anybody who can't manage to do it without ****ing something up can certainly count themselves into the ranks of the Klutz category. Take it slow and easy.