Stock to Fuel Injection End Casting Conversion

[CBDZ]

Since currently I have more time than money, I can't justify spend close to $200 to purchase CB Performance end castings, and fuel rails. I thought that I would modify a set of stock ones that I have, and show how I go about doing it, with simple shop tools. I have had to buy a 1" diameter hole saw, and about $30 in aluminum. I bought 2 feet of 1" square stock for about $12, and need to go back to get some 1" round stock. With that, I should be well under $100 bucks for the complete assembly.

The first task was to find out where to mount the injectors, and at what angle. I started by measuring and drawing the end that attached at the head. Simple enough, since I am an architect, and use Auto-CAD on a daily bases. Based on my measurements, the ports are approximately 1-3/16" in diameter, and spaced about 1-3/8" apart. Now finding the angle was a little more difficult. If you try to go 90* from the ground, you will run into trouble because the 3 & 4 cyliner intake runners are on top of each-other too much. After looking at it, measureing, and partially getting a little lucky, I found that 13* in relation to the mouting flange was just right. (Now these are going in an open engine bay buggy, so I don't know if this would work in an enclosed engine sedan.)

The goal is to have the injectors aim directly in the center of the port on the head. Currently i am working with stock heads, with no porting work done on them. So I made a jig. My jig, since this was a one time deal was made of some scrap 1" pine planks that I had laying around. If this works out, I may rebuild the jig using something more durable, and offer conversion services for a small fee... So, the drawing that I created is actually two patterns that are super-imposed on top of each other like this...



I messed up when I nailed the spacer to create the angle, and put the 2x4 over the holes for the bolts, so I just tranfered them down a little. The jig is lined up with the drill and the hole in the middle. The jig stays in place, while the manifold is adjusted to the next position for cutting.

With the jig, all the injectors should be the same angle and position in relation to the intake port on the head. Here is a picture or two of the very crude, but effective jig.






Next I cut the holes with the 1" hole saw. Sorry that I forgot to take action shots while doing the cutting. I initially tried to drill a small pilot hole, but because of the angle of the intake, I had better results just using the hole saw, with out a pilot hole.

Here are a few pictures of the results...





The next step is determining how tall the mounts can be. I want them as low as possible, but there needs to be enough material to create a seal with the injector O-Ring. I need to create a drawing to illustrate what I am talking about here.

I have purchased 24" of 1" round aluminum for $8. The fit is alomost perfect.




Let me know if you have any questions, suggestions, or comments. I am having fun with this, and I really hope it works out as planned.

[CBDZ]

I made edits above, and added pictures.

[fastback]

nice, keep us posted with more pics

[CBDZ]

So I have not been able to do much, until tonight. Because this is something that I want to achieve with basic tools I am having a slight dilemma as to how to bore the hole through the 1" diameter aluminum. I have made a "chuck" out of wood as test. It may or may not do the trick. If it doesn't, I may buy a mini-lathe chuck taper that has a MT2 shank, which is the same as my drill press. I will use the Jacobs chuck from a standard drill, and mount it to the press table. I will have essentially created a vertical lathe for the purpose of center boring the injector bosses.

Pictures are on the way.

[MarioVelotta]

Way to take the bull by the horns. I have wanted to try this for a long time... It's just so easy to call up CB But in my fuel injection kits this may make for a lower priced alternative to those that are trying to do thing on a very tight budget. Now it would be really cool if you where to use some 1" solid stock with the injector boss in that. Then the insides of the ports could stay stock in shape with a little porting work.

Keep us posted

[CBDZ]

After a few hours of messing in the garage, trying to make a fixture that would allow me to center drill the 1” aluminum stock, I have determined that this will not work. I cannot get the precision that I was hoping for. No big deal. Cost me about $1.50 in bolts.



So the next attempt is to buy a chuck from a lathe. Based on all my research, the chuck on my drill press is a Morse Taper #2. So this is what I am going to buy. $30.00 is not to bad in my opinion.


http://www.harborfreight.com/2-inch-min ... -4486.html

I will need to make a tool so that I can mount the standard chuck on the drill press table. I will then be able to mount drill bits in stationary position, and turn the material into the drill. This will hopefully provide me with a hole centered on the aluminum rod.


Here are a few pictures of a 5” section of aluminum that will make the injector boss. Currently this is a full diameter, but it will be shaped so that it follows the contours of the stock manifold.

[panel]

Got to love the DIY'er. I did my own also.(IDA/IDF style manifolds though)

[Jadewombat]

Great stuff, keep it coming. I added your thread to the sticky at the top of the page.

I made my jig a little differently out of steel to get the same spray angle VW used to the back of the valve. Since the drill bit comes in at a angle on the jig and it would want to push off to the side, I first used a small milling bit to get a surface started then drilled with a regular drill bit. The hole was just big enough so the injector tip would poke through the end casting. Then it's just a matter of welding up one of the aftermarket injector bungs sold by DIYautotune, SDS, 034, etc. or some aluminum tubing if you plan to use CIS injectors (so the o-ring can press in with the injector).

[Rugbykoen]

Nice, because i don't have the money to buy expensive end castings, i think this might be a sollution for me! Is it possible for you guys to post some final results?

[CBDZ]

Progress has stalled a little with vacations, work, and life getting in the way.

Currently I am trying to determine the best way to drill the.holes where the injection will mount. I would like to have the use of a lathe but I may just have to use the.droll press.

[Rugbykoen]

Ah oke, that's all clear for me. How do you think to remove the material inside the manifold nicely?

En, do you allready got an idee how to fit a fuel rail? Make one by yourself, or use a stock version?

[CBDZ]

After messing around to much with a drill press, and other goofy ideas, I finally found somebody that would let me come to their shop and use a lathe to center drill the 1" diameter bars to accept the fuel injector. I know this is techinically cheating because I wanted to do this using typical tools that mosy guys would have in their garage.

All the research that I have done says that the injector bore should be 14mm. McFadden-Dale Hardware, in Anaheim CA didn't have that size in stock, so I went just a little smaller. This was probally a good idead since the chips and shavings from drilling made a few gouges in the wall. I will be able to use some fine sand paper to smooth out the holes.

This is a shot of two of the bosses drilled.



This is how they will mount.





The next step is to rough cut off along the redlines so that i am following the contour of the inside of the intake tract.

I am hoping to get these wrapped up soon.

[miniman82]

I think when it's all said and done, you'll have put way more than $200 worth of time into this. You get an 'A' for effort though, I like the ideas.

[CBDZ]

Very true, but my wife doesn't see the $200.00 of my time that is missing from the bank account.

[73AZ]

If you had sourced inexpensive injector bungs than
both points just raised become moot, no?