DIY Injector mods

[Cold Roller]

Rich, nice shims!

So I finally got the injectors in the truck over the past 2 days. I did the ARP head-studs as well one-by-one. All I can say is that cab-off would have made this one easier. Without evacuating the AC and just pulling the HVAC box straight out, I decided to pull the exchanger, first but it wasn't playing nice and was a biatch to get out of the HVAC housing. Of course, on the install it slipped right in without much effort! Then I get a sinus block that made my head pound anytime I laid on the engine to do any work...

Two 20 second cranks and 8 seconds of power-up cranking to start it. It idled nice with just a very slight lope for 2 minutes.

So, here is a vid of the idle after driving it to work and back today (40 minutes each way).

https://www.youtube.com/watch?feature=player_detailpage&v=LwKTc7r39fU#t=0s

So here is what I did. I will be the first to admit that I made a slight measurement mistake (so I won't post what I cut to), because I didn't initially figure in how much wasted plunger bore I should have used. So after it was all said and done, I took out the spool shim to give me the chamber volume I wanted and where the plunger would sit relative to the spill port. Had I left the shim in, my chamber volume would have been about 0.215cc (215cc injector), but 35cc would have been above the spill port, and that was probably too much. My understanding is that a volume of 0.205cc will yield about 0.188cc with some loss out the spill port. I am just guessing here, but if too much goes out the spill port before the plunger covers it, it probably would not start or idle very well.

So now that I have bored you with that, this is what you do.

Turn down the intensifier piston the amount you want to increase your stroke by. If you use 0.050" that gives a stroke volume increase of 0.040cc. So your stock injectors can now move 0.175cc (175cc injector).

Of course, if you don't also reduce the plunger by some amount, your plunger would strike the fuel plate and probably destroy the injector. So now you need to cut 0.026" off the plunger to give a full stroke. However, you must ensure the plunger is not proud, so it might be a good idea to cut 0.030" off. I understand you can turn this on a lathe as well, but because of the DLC, the shop used a diamond lapping cutter. The tolerances are all to 0.0001". Look at the end of this one compared to Lilpooh's pic above.

I had my nozzles extrude honed to 75% over by Chatham Fuel Injection services in Canada. Just under $400 with shipping and taxes.

I made a holding tool as well, but out of aluminum. It must me able to hold it tight, because you need a lot of force to unscrew the body. FWIW, my injectors were all eBay purchases, 2 used, 2 Alliant remans, and 4 BWD remans. The total cost to buy them was $600 over a few weeks. The cheapest one, $56, was the prettiest of the bunch! No core charges. They all looked the same internally and measured similar tolerances. The 2 used ones had partially blocked nozzles. One Alliant has a slight blockage as well (who would have thought!). All would have worked in a stock truck without problems. This did not affect the honing, although the used ones take longer due to case hardening from engine heat.

So, for $1,200 and my time to figure it out, I got 8 injectors at 185/75.

For my slightly goofy cut, I also have the option of plugging the spill-port (3.5mm brass plug) to bring them up to 215cc. But one thing to consider about the spill-port, it is designed to let high pressure fuel bleed out before it is squeezed into the oil side of the injector.

There are other ways to increase chamber size, such as the shims above, but these 2 methods set the injectors to run very close to normal for easy starting and idle characteristics.

Another concern to keep in mind is the fuel plates themselves. It is probably necessary to increase the space available between the plates to have enough fuel to fill the larger chambers (above 190). If you didn't look closely, you might miss how small the space between back half of the fuel plates is!

Of course, you need a bigger turbo or you will just blow smoke. I crafted a 63.5/88mm wheel and housing to my powerstroke back-end. It works well, but not good enough for a large PW tune with these injectors. Temps are OK, but it will smoke a bit.

One last note, crazy fuel milage. I average almost 28mpg today compared to my typical 19mpg. I just had on the canned SCT Performance tune (if you can call it performance) to ensure it would start and run without over-fuelling issues.

This all started as a what goes into what makes the magic. It ended up with me following through to a final conclusion. If I was in the USA, I probably would have just sent the pieces to Renegade, but shipping in and out of Canada was going to be a PITA.

Look at some of my channel vids. Here is one to show plunger movement.

https://www.youtube.com/watch?feature=player_detailpage&v=GU8ERlPGiWw#t=0s

 

[Cold Roller]

2 more vids of injector parts.

https://www.youtube.com/watch?feature=player_detailpage&v=3GyVzEE2Si8#t=1s

https://www.youtube.com/watch?feature=player_detailpage&v=AznIFD6lpZ8#t=1s

 

[Extended Power]

Wicked information.

I do alot of "Cross-Border" shopping, and shipping...but I am only 2 to 2 and a half hours away from the borders. (Coutts, and Wildhourse.)

With the Extrude honing...how do they control the total amount removed from the tips?
I mean, yeah, they say they used the same amount of pressure each time, but how do you know that exactly 75% was the outcome?

 

[Stroker04]

Great information!

 

[TheReelMuhcoy]

Cold Roller,
I believe this is my 5th time reading reading your post and watching your videos (took that many times to comprehend and absorb). I'm Blown away by your FANTASTIC information.

Who is "Renegade"?

I have not yet had the opportunity to really do the math, but I am still at a toss up between 190CC and 205cc injectors. I could make the "oops" that you did and just shim accordingly, then remove if and when I want to try to run 205cc's.

I would like to run 75% nozzles as well, any recommendations on where to obtain or should I modify my stock nozzles? Any trusted companies in the States that we can send them to?

 

[Cold Roller]

With the Extrude honing...how do they control the total amount removed from the tips?

They run a flow check with air to determine initial calibration. typical new nozzles flow about 170-175 l/min. Then it is just a matter of time. They run 3-5 cycles of varying time (depends how fast it changes the flow) of an abrasive medium through each injector nozzle to determine the standard. So, for 75% nozzles they would flow about 305 l/min when done (295 - 315 for mine). Older nozzles are harder so the first pass is usually twice as long. As long as the nozzles close properly, they basically become new again at the new flow rate.

Should I modify my stock nozzles?

If you can afford to have the truck down while you wait or during the DIY build, no problem.

EDM is the other method used to make new or larger holes. You can get nozzles from a few companies including, some of the sponsors plus a few others such as renegade diesel (facebook), Lubeowner, Elitedieselengineering. Prices are $480 and up.

You should know that every group selling different nozzles flow rates them differently. So brand X 75% over may be the same as brand Y 60%. In any case, 175s or less only need 50% at most for min time max PW flow. The same argument could be made for 190s as well, but at some point you need a larger nozzle. 75% nozzles or larger will mean haze at lower engine RPM if the turbo is not spooled or fuel is not pulled in the tune until boost/MAF is increased.

 

[nitrogen here 2]

is that 28 mpg number off the dash or by tank fill?

 

[Meniacal_Mark]

Subbing opcorn:

 

[02POWERSTROKE7.3]

Subbed

 

[TheReelMuhcoy]

I ordered my reseal kit last night, and received a PM from a vendor who EDM's blank injectors, I will be ordering them in the next week or so.

Not to derail this topic but, I am putting together a fuel system using an a1000. I plan to replace the fuel system when I do the 6.0.4 project in preparation for larger injectors. I do not plan on using an AD of Fass, so I need some sort of filtration and water separation. Does anyone have a filter cartrige/setup suggestion? I would like use something like this http://item.mobileweb.ebay.com/viewitem?itemId=360474893344&index=22&nav=SEARCH&nid=62170196463 the first filter a coarse micron water separation filter and the second, a fine micron filter.

 

[Cutting-Edge Diesel]

is that 28 mpg number off the dash or by tank fill?

Your mpg on the dash will read way high with aftermarket injectors

 

[Cold Roller]

That is what I thought... Probably due to the PCM using a stock injector profile and ICP/PW for the calculation. I wanted to go back and edit the post, but the time to edit had expired. I now runs less boost at highway speed due to APS position, so I should expect some gain.

 

[Mdub707]

Great info here...

 

[TheReelMuhcoy]

OK, so I did some calculations for another member who asked for assistance with calculating how much material to remove from the Intensifier Piston and Plunger.

This is the base # I came up with for a 205CC Injector. (also consider what Cold roller says about slightly over cutting the plunger so you do not crack the fuel plates):

Cheers!

PS. I converted to CM to start to make calculations simpler. If ColdRoller or Lilpooh can look over the #'s to make sure I am calculating right I (and everyone else) would appreciate the confirmation.

 

[Cold Roller]

Surface area is Pi r^2
D=6.347mm
r=3.174
A=3.1416*(3.174^2) = 31.64mm^2
70mm^3/31.64mm^2= 2.21mm (0.0870")

Your math is correct, but you don't want to take 2.21mm off the intensifier piston. The regular injector volume wastes some fuel that is held above the spill port. I would suggest that you need 6.5mm of barrel length, maybe a bit more at rest. 6.5mm of barrel gives a chamber volume of 205.7mi^3. So you would only need about 1.55mm (0.061") off the intensifier piston. This is why you need to measure twice and cut once. The plunger would be cut less than this to use excess barrel. A rough number would be 0.89mm (0.035") off. Whether I am 100% correct is unknown since I did not flow my injectors, but volume below the spill port is certain and volume above the spill port is only partially available for the stroke.

Who knows, maybe someone with the tested data will offer a sizing for the cut.

 

[Cold Roller]

I measured another set of injectors this morning. The intensifier bore depth was out slightly on some of them. I had similar results on the first set as well. Lilpooh shows 0.029" as the space available, but I had a few that were as tight as 0.025". It would be a good idea to measure the shims to see if they are different thicknesses as well to make up for the bore depth. Most of the ones I have seen are within 0.002 of each other.

After thinking about it a little longer, it is probably a good idea to leave a minimum of 0.005 as a buffer for the plunger to fuel plate clearance. So what ever you cut from the intensifier piston, cut 0.020" less off the plunger. I would cut 0.035" max of the hammer end of the plunger, and cut the remaining amount from the clevis end.

So in the previous post, the chamber would need to be 6.63mm deep to keep the plunger safe from bottoming out. and the total stroke would be 6.5.mm. Again, keep in mind the plunger in a stock injector sits about 5.6mm from the fuel plate at rest (volume 177ml) but does not travel full length (loss of 22ml) and looses some out the spill port to give about a 135 injector. This is why a simple plug give you a 155cc injector. This is also why you don't necessarily need to cut 2.21mm off the intensifier piston to achieve the desired travel. You could, but it is not as efficient as moving the plunger down the bore. I initially said about 1.55mm cut, but it could be up to 1.9mm or even 2.2mm, depending on how much spill you are willing to take. Again, keep in mind that you are reducing the plunger by a smaller but similar amount and it will increase the resting point further above the spill port.

 

[TheReelMuhcoy]

I have not yet opened an injector to see how the spill ports work and whatnot so just from my general speculation, here is how I came to my numbers:

Assumed stock plunger length makes 135CC's and we want to make 205CC's that is a difference of 70CC's per 1000 injections. Therefore we want to increase the fuel barrel by 0.70CC's per injector.

It was a very simple calculation assuming a simple injector operation, although my calculations do not consider the influences of the spill port.

 

[nitrogen here 2]

for a really nice filter system look at Davco

 

[Cold Roller]

Hey man when you cut the intensifier piston what are you using to cut it with? Where exactly do you cut it? I'm still trying to get my math straight here on how much I need to cut exactly to get X cc's.

Someone asked, so here is my answer and my take on a 190cc cut.

Cut in with a carbide cutter on a lathe. If you want to do it without a lathe, you can use a higher speed drill press with a softer metal collet to hold the piston. You could have a carbide in a jig and lower it very slowly to cut material off. You could even use a diamond file or carbide file on a flat surface as well (easier to control the cut). You could do the opposite set-up as well. Another way is with a high-speed med-fine grit diamond wheel and a jig to hold the piston true. You cut the skirt (side with the hole). But why? Just pay the money if you don't have the tools.

The plunger can be done the same way. We used a diamond lapping wheel, but a diamond or carbide would be just fine. We just didn't want to possibly damage the DLC.
Cut the bottom or hammer end up to .035". Use the other side for any remainder. This way you will not compromise the DLC on the plunger.

For a 190 injector cut about 0.065" off the intensifier piston and 0.045" off the plunger. Remember that the 0.035" you take off the plunger does not affect the DLC or even the spill-port interaction. You could probably cut a slight bit more off and get more flow, but it would be very minor power-wise and only at WOT.

 

[Cold Roller]

I came across an article that quotes the injector body torque spec at 55lb-ft. Initially I quoted 85lb-ft. Perhaps it was a transcribing error. In any case, 55-60 should be more than enough torque. I used 60 when I did mine, just because it seemed like a lot and the injectors started to spin in the holder.


I can't remember if I mentioned it before, but the pressure from the holder actually causes the intensifier piston to bind until the vise pressure is released. Be careful in applying too much vise pressure.