DIY Injector mods

TheReelMuhcoy · Mar 27, 2013

I was reading the March and April editions of Diesiel Power Mag while flying to Brazil for vacation. I noticed each month had interesting topics on HEUI injectors, one was how they worked - the injection process from the HPOP to the injector tip. The other was a write up on Elite diesel's 155CC Torq Tow DIY injector kit.

Of course my brain starts going and putting the two together. I understand injectors have very tight tolerances, but with the right assistance and knowledge could one modify his own injectors to grain the same results that we are paying large $$'s for?

I do not have a flow bench to test what my hypothetically modified injectors are flowing, however couldn't we calculate a rough flow # based on the change in volume from modification?

Trying to think outside the box...

Jon

Mdub707 · Mar 27, 2013

There was a good thread about this already, check it out: http://powerstrokearmy.com/forums/showthread.php?t=29804&highlight=elite

TheReelMuhcoy · Mar 27, 2013

Mike,
I think I need to learn how to use the search feature of this Forum. It seems like any time i try to search for something I get ZERO results.

Anyhow the link you posted is a great start. However there is not much about the machining of plungers to allow more volume in the fuel barrel. I think that will be my angle of approach, maybe a combination, but shimming the spool valve seems like a cheaters method and can result easily in a failed O-ring. I can always send the injectors out to a vendor who can flow test them for legitimate specs.

Pizza pig · Mar 27, 2013

Heh you'd be surprised what companies just use a thicker shim to call them what they call a certain injector. Only works to a point but it is done time and time again.

TheReelMuhcoy · Mar 27, 2013

Not to knock Elite Diesel but their new kit for 170cc DIY Mod, they advertise the use of a "Spool Valve Spacer". I have no idea what the spacer size is and what stresses that creates, so maybe its perfectly acceptable for that application, but if I am modifying my injectors I would really like to try to achieve 190-205cc, and I would like to do it the most reliable way possible.

willholl79 · Mar 27, 2013

Tagged for info.

Lilpooh · Mar 27, 2013

More info.

http://www.powerstroke.org/forum/6-.../333002-modifying-injectors-larger-flows.html

SSpeeDEMONSS · Mar 27, 2013

A 170 DIY? Sweet! That sounds good to me! Does anybody happen to know the size of the shim?

Garrett

probably getting paid at work to post this from my bionic

TheReelMuhcoy · Mar 28, 2013

More Mooore MOOOORE! Dude I've shut myself out from other diesel sites, I am devout to PSA... But reading the information provided from knowledgeable members here on other sites isn't cheating, is it? Love my PSA. (Sorry I'm a few 600ML bottles deep here in Brazil, they know how to drink)

I am now seeing the big picture, but I need to do some math to determine how much I need to remove from the plunger to achieve 190-205cc's. I guess I should aim for the middle and then shim to the desired performance? Sounds like a solid achievable plan, then send out to a flow bench to confirm.

Mdub707 · Mar 28, 2013

There's SOME good info out there, but not a ton. Basically, you're not going to find a step by step DIY on machining injectors, because the guys who know, probably don't want you to know, as it will lose business for them. Keep us posted as you go, I'm looking into the same kind of thing. My problem is I haven't had an injector apart...yet. Once I have one in hand and take it apart, it will likely make a lot more sense to me what needs to happen.

Lilpooh · Mar 28, 2013

From what I've gathered, there are different methods to obtain fuel volume in the injector. Cutting the fuel plunger and oil piston. Shimming the spool valve body away from the injector body. Plugging the spill ports. Shimming the fuel plates away from the injector body. And/or any combinations of the mentioned, depending on how big you want to go.

You can even make your own vice clamps for holding the injectors by using 3" x 4" x 1/2" thick steel with a 7/8" drilled hole in center and split the piece in the middle.

TheReelMuhcoy · Mar 28, 2013

Lilpooh,
Great info there, are these your photo's or photo's you found? Either way they are great help for visualization. I like the steel plate drill & split for the holding tool, thats a huge help. I wish that there were someone here who has attempted this themselves already that could give some first hand trial and error/results.

STR8LINE · Mar 28, 2013

Hey Good thread! Hopeing some Experienced ppl step in here an enlighten us with thier first hand experience here ..

MorganY · Mar 28, 2013

TheReelMuhcoy said:
Lilpooh,
Great info there, are these your photo's or photo's you found? Either way they are great help for visualization. I like the steel plate drill & split for the holding tool, thats a huge help. I wish that there were someone here who has attempted this themselves already that could give some first hand trial and error/results.

Don't break those two dowel pins sticking out of the body....lol. And when you first pull one apart, have a clean towel under it so you can be familiar with what comes out. As you can see, there is a whole bunch of little sh*t.

Lilpooh · Mar 28, 2013

TheReelMuhcoy said:
Lilpooh,
Great info there, are these your photo's or photo's you found? Either way they are great help for visualization. I like the steel plate drill & split for the holding tool, thats a huge help. I wish that there were someone here who has attempted this themselves already that could give some first hand trial and error/results.

These are my pics, I've got more. Frank (twoicebergs on org, Cold Roller on PSA) is way further than me, I just got my feet wet. I have no interest in building injectors, I'm in it for the education and just to see if I can do it.

Here's a shim I made for between the injector body and fuel plates, this little sucker has to be dead nut for dowel pin to plunger alignment. And that's all I can say about that.

And a short video showing a DIY process of cutting carbide if you don't have access to a diamond wheel grind lathe. The diamond compound can be bought for around $35.

http://youtu.be/AMD-LtaXRFc