# non-airshrouded injectors on digihead, which holders?



## ziddey (Apr 16, 2006)

I'm rebuilding a digifant head for use with cis-e, and am getting mb 190e brass injectors. Since the digifant head doesn't have provisions for air shrouding anyway, I'm wondering which holders to use. I had previously bought the airshrouded holders (brass upper and plastic lower). Will these work ok? Or should I get the all plastic holders, 063133555A http://www.autohausaz.com/search/pr... Air System&[email protected] Injector Insulator 

Or is there a better holder available elsewhere from autohausaz?


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## WaterWheels (Aug 14, 2005)

ziddey said:


> I had previously bought the airshrouded holders (brass upper and plastic lower). Will these work ok?


 What I have found, others claim different so maybe it is a haed to head thing or . . . , is that the hole under the threaded hole is too small and not tapered for use with the lower CIS-e inserts. So the air shrouded setup (both parts) will not fit. Here is how I worked around this and you can do the same or come up with you're own idea once you see what I did. 

I used the upper brass inserts, but I shaved about 5mm off the bottom (maybe a little more as I can't remember exactly). I went to the hardware store and purchased some plastic spacers which I can not recall what their real use was, but they were about 5mm thick and had a hole in the middle. I enlarged the hole so the injector would just fit in and sanded the outside until it fit the injector hole good. Dropped the plastic spacers in the hole, threaded the brass insert in using some sealant and pushed the injectors in. They still wanted to lean to one side due to the weight of the injector lines, so a fabricated a simple holder for them. Kind of like a fuel rail, but just a bar with very small "U" clamps to hole the in the correct spacing and the bar held to the head.


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## earplug (Aug 10, 2008)

http://www.autohausaz.com/search/pr... Air System&[email protected] Injector Insulator


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## WaterWheels (Aug 14, 2005)

Can only go by the picture, but they look to be the early CIS inserts. Maybe they are custom parts, if so then fine, but the early inserts are 24mm and the newer ones are 22mm.


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## earplug (Aug 10, 2008)

WaterWheels said:


> Can only go by the picture, but they look to be the early CIS inserts. Maybe they are custom parts, if so then fine, but the early inserts are 24mm and the newer ones are 22mm.


 no good then


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## superl8 (Dec 31, 2002)

WaterWheels said:


> What I have found, others claim different so maybe it is a haed to head thing or . . . , is that the hole under the threaded hole is too small and not tapered for use with the lower CIS-e inserts. So the air shrouded setup (both parts) will not fit. Here is how I worked around this and you can do the same or come up with you're own idea once you see what I did.
> 
> I used the upper brass inserts, but I shaved about 5mm off the bottom (maybe a little more as I can't remember exactly). I went to the hardware store and purchased some plastic spacers which I can not recall what their real use was, but they were about 5mm thick and had a hole in the middle. I enlarged the hole so the injector would just fit in and sanded the outside until it fit the injector hole good. Dropped the plastic spacers in the hole, threaded the brass insert in using some sealant and pushed the injectors in. They still wanted to lean to one side due to the weight of the injector lines, so a fabricated a simple holder for them. Kind of like a fuel rail, but just a bar with very small "U" clamps to hole the in the correct spacing and the bar held to the head.


I did this as well. But I used washers with rubber bonded to one side. Dropped one in each injector hole then threaded the inserts in and deleted all the plastic shrouding pieces - plugged the inlet as well. Worked very well in my opinion. I just browsed through the washer section at the hardware store to find these - with an injector in hand. The fit was perfect snug in the rubber - essentially sealed twice - once with the fat o-ring and then again with my washer retrofit.


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## ziddey (Apr 16, 2006)

Ok, so the early non-shrouded cis holders are too small is what you're saying. Cis-e and digifant share the same size, but the air-shrouded lower inserts will not fit the digifant head. Forgoing a lower insert will result in the injector leaning too much.

Is making a custom lower insert the only way?

I haven't done anything in regards to the build yet, but am about to start. At this point, I'm thinking of ripping the head off my 85 gli and using that. Then, I'd just swap the small valve cis-e head into the gli and figure out the digifant head some other time.

How much of a difference are we talking about with the cis-e lower inserts vs the bore in the digifant head? No way I'd be able to just shove it in? I just swapped the lower inserts on the gli today, and from what I saw, it doesn't look like there's enough thickness on the lower inserts to shave them down some. And considering how thin the lower inserts are, if they don't fit, wouldn't the injectors be fairly tight in the bore to not lean that much?


Also, anyone know anything about mercedes lower inserts? http://www.autohausaz.com/search/pr... Air System&[email protected] Injector Insulator

If I could fit that onto the cis-e brass upper inserts, maybe that'd fit?


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## JoggerNot (Nov 6, 2009)

How come we cant use the digi inserts? Seems it would be easier to find smaller O rings to fit down in them..Or is there a hight problem with the digi ones ?


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## ziddey (Apr 16, 2006)

EFI injectors are very different from CIS injectors. I'm assuming there's no way they'd work. Hell, I really need to just grab all the parts out of my jetta's trunk, and start figuring things out in my room. The block is the only thing I can't bring inside, and there's really not that much I'll be doing to it. I want to change the crankshaft seal, but I'm thinking I won't be able to get that bolt off, especially just working on the block by itself.


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## JoggerNot (Nov 6, 2009)

Because the the injectors dont fit ? Or because they sit to high/to low ? I mean, I can get a one of the cis jets in there through the hole. The rubber seal ring on the injector just wont fit.


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## WaterWheels (Aug 14, 2005)

> Because the the injectors dont fit ?


Yes, unless you want to get into tiny details. 



> The rubber seal ring on the injector just wont fit


Exacty.



> Or because they sit to high/to low ?


That also, they would come to close to the bottom of the intake runners if you could insert them into the inserts as the holes are made deeper for Digi heads.


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## JoggerNot (Nov 6, 2009)

So it sounds like these brass ones are the 22mm ones that fit in the digi head. It apears these http://techtonicstuninginc.com/main...id=650&zenid=e64957d69a1ce717dc291aa93c9ecaa8 sit in the brass insert. Can't the injector just sit in that ? I'm afraid I don't understand the problem. Is it just that you need a good seal ?


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## nairmac (Jan 22, 2004)

I'm running CIS on a Digi head and had basically the same problem. I used unshrouded injectors and no lower cup, just the CIS upper screwed into the head with new o-rings. It works fine.


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## WaterWheels (Aug 14, 2005)

JoggerNot said:


> I'm afraid I don't understand the problem.


I'm not going to read back through to see if I did explain this, but I am sure I did. The holes in the Digi heads where the injectors fit are machined different than for CIS heads. The CIS head has a wider and tapered, a little, hole to allow the part you linked (the lower plastic piece). The Digi heads have a smaller hole which has no taper, has to do with the injector size and how they need to sit to spray into the runners right. You can have a machine shop cut the lower part of the hole to fit the air shrouded injectors, but the cost way out weighs the benefit. So people just use the upper half of the insert set, remove the stainless steel "Top Hat" at the end of the CIS injectors (or use the older models), and call it a day.


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## JoggerNot (Nov 6, 2009)

Then insert the insert into the head...But it needs something else to go with it so thats where this idea of a bushing or something comes into play.

What if you drilled a bigger hole in the digi injector cups then rubberized the edges and slid the inserts into them ?


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## ziddey (Apr 16, 2006)

nairmac said:


> I'm running CIS on a Digi head and had basically the same problem. I used unshrouded injectors and no lower cup, just the CIS upper screwed into the head with new o-rings. It works fine.


great, that's what i wanted to hear. going to order the brass injectors now. so injector lean isn't going to be a problem. sweet. build should be occuring in the next few weeks 

thanks


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## WaterWheels (Aug 14, 2005)

JoggerNot said:


> What if you drilled a bigger hole in the digi injector cups then rubberized the edges and slid the inserts into them ?


The hole in the Digifant injecter incerts is large enough for the CIS injectors to pass through without the air shroud caps on the end. There would be zero value and maybe dangers with leaving the air shroud caps on and sticking them into the runners. You seem to be trying very hard to make things harder then they are? Have you ever seen or heard of the acronym K.I.S.S?


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## Glegor (Mar 31, 2008)

WaterWheels said:


> The hole in the Digifant injecter incerts is large enough for the CIS injectors to pass through without the air shroud caps on the end. There would be zero value and maybe dangers with leaving the air shroud caps on and sticking them into the runners. You seem to be trying very hard to make things harder then they are? Have you ever seen or heard of the acronym K.I.S.S?


@ WW - this kid always has a better idea in his head. i will throw out an idea that works, and needs no modification, then he starts in with the "what ifs" and "if i did this differently" or ... you get the idea. 

he has to hear the same thing from 40 people before he just goes with it.. lol. 

the solution to this plan, the easy way, buy an 85-87 CIS-e head.


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## JoggerNot (Nov 6, 2009)

WaterWheels said:


> The hole in the Digifant injecter incerts is large enough for the CIS injectors to pass through without the air shroud caps on the end. There would be zero value and maybe dangers with leaving the air shroud caps on and sticking them into the runners. You seem to be trying very hard to make things harder then they are? Have you ever seen or heard of the acronym K.I.S.S?


This just seems so simple and I guess I'm not sure what the deal is...As long as the injector is stickin down there at the right "in" and sealed then..

Kev- Not recently as I'm in waters you havn't yet sailed :>

Uh hydraulic head ftw.


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## WaterWheels (Aug 14, 2005)

JoggerNot said:


> This just seems so simple . . . As long as the injector is stickin down there at the right "in" and sealed then..


And what exactly is your problem, if you have one, with SIMPLE? As for the injector height, if it sits to low and is close to the bottom of the intake runners, instead of a fine mist being drawn into the combustion chamber you get droplets of fuel which does not burn as well.


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## JoggerNot (Nov 6, 2009)

WaterWheels said:


> And what exactly is your problem, if you have one, with SIMPLE? As for the injector height, if it sits to low and is close to the bottom of the intake runners, instead of a fine mist being drawn into the combustion chamber you get droplets of fuel which does not burn as well.


I don't have one I guess....I was just interested to see what was going on 
So essentially, you want just the tip of the injector sticking down....

Thanks for the help!


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## Glegor (Mar 31, 2008)

JoggerNot said:


> This just seems so simple and I guess I'm not sure what the deal is...As long as the injector is stickin down there at the right "in" and sealed then..
> 
> Kev- Not recently as I'm in waters you havn't yet sailed :>
> 
> Uh hydraulic head ftw.


 oh no, i knew i was gonna have injector cup problems the day i realised it was a digi head. then i never worried about it. cause if it turns into too big of a hassle, i will just use the head that is on my HT 1.8, then EVERYTHING will hook up just like its supposed to! 

not that i hadnt thought of it, i just didnt worry about it, cause i have a "get out of jail free" card.. 

i really wish i could find an 84 GTI head.. i love the tappety tap of the solid lifters.. 

DIESEL FTW!!! lol


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## JoggerNot (Nov 6, 2009)

So my plan right now is to use digi cup threads and cis cup holders. I'll glue and seal the halfes together and screw em in. Can change the height easy by more or less shaving..They shouldn't break as I will glue both sides... 

Any thoughts ?


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## Glegor (Mar 31, 2008)

JoggerNot said:


> So my plan right now is to use digi cup threads and cis cup holders. I'll glue and seal the halfes together and screw em in. Can change the height easy by more or less shaving..They shouldn't break as I will glue both sides...
> 
> Any thoughts ?


i highly doubt your glued together injector cups are going to work. (for very long) otherwise all the good mechanics would be gluing injector cups together..


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## JoggerNot (Nov 6, 2009)

Glegor said:


> i highly doubt your glued together injector cups are going to work. (for very long) otherwise all the good mechanics would be gluing injector cups together..


I'll get em together.


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## Glegor (Mar 31, 2008)

WE NEED SOME OF THESE INJ CUPS!!! anyone know what there from/for?


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## WaterWheels (Aug 14, 2005)

I can not be 100% sure, but they look like pipe fittings. I remember reading somewhere a while ago about someone finding and using some standard pipe fitting, maybe modified a little, to hold injectors in a cylinder head. It was complete with picture if I recall and that picture might have been one of them, but I'm not sure.


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## Glegor (Mar 31, 2008)

i wish i knew what kind of pipe fittings they were. especially with 22mm metric threads.. and they have the ledge for where the injector o-ring sits.. those things look to be the perfect height..


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