All good points mickmini so I'll run through them:



Lots of room. In the pics above I have sketched the flanges and the body of the head but not the cast intake runners joining the two. The rocker cover sits back from the front of the head part by the thickness of the head stud nuts.

The runners drop sharply from the flange down to the valves so there isn't anywhere the injectors can meet the shape nicely, except for having nearly vertical injectors. Worth a measure and see though.



The flange is too high, too far out and too big, you are correct but the height and distance allow access to the spark plugs. IMO for a round nose they should offer a version of this head with inlet ports that come straight out and are much smaller. Meeting up with the 40mm Weber pattern makes the ports too angled and too big.



All of these are possible and would probably result in an improved overall finished product. However, I am trying to keep the head virtually stock to retain its possible resale value and I want my manifold to go on an unmodified head in case anyone else wants one and doesn't want to modify their head. So far all I need to do to the head is cut shallow injector pockets at the top of the ports and drill and tap between the ports for extra studs to replace the top mounting studs which would get in the way of the injectors. Neither of these would stop the head being used with Webers later.

I like your thinking with all these ideas, thanks.

M

just remembered there is a pico size of injectors. not sure if Bosch make them, but Siemens Dekka does. they are so small that the connector looks completly out of place.
found this pic, but no dimensions so i don't know if they are a direct replacement for the EV1 or 6 style
http://www.high-speed-tuning.de/images/ ... 5865_0.jpg

_________________
Rover 214 atm ....

Good find Klas.

Ok, so now I have three options.
(1) use the set-up as-drawn if the bonnet measurement shows there is clearance
(2) use short injectors like the ones Klas has pointed out
(3) modify the head using mickmini's suggestion.

Number 3 is looking really good (thanks mickmini). I have had a look and I could keep the Weber flange and put the injectors into the runners between the Weber flange and the head. Here are some pics.

This is the area available. There are two bosses for vacum take-off but only one is drilled & tapped. They would have to go.


The stock Bosch injector fits in there.



And the fuel rail would be lower than the oil cap.



They poke into the ports nicely. In the real version they would be angled so that they point down the port better.



So I'd need to get some of these (or simlar) TIG welded into the head.

http://www.efihardware.com/products/233 ... oy-weld-on

Or these which can be screwed in.

http://www.efihardware.com/products/104 ... -BSP-alloy

There are others I like better because they aren't tapered but I can't find them right now. EDIT: Here they are: http://www.ausmini.com/forums/posting.p ... t&p=849758

The thing I like about mickmini's idea is that with the injectors in the head, the intake plenum flange can use the stock Weber mounts in the head and the plenum will be heaps easier to make & seal. I could then use stock 10mm or 12mm alloy plate for the flange and just laser cut it. The current design for Weber injectors is 20mm and needs to be water jet cut and machined. (Denso one is 16mm)

It also allows something like this in between for quad throttle goodness.

http://www.efihardware.com/products/185 ... e-DCOE40mm

But that would be way out of my budget...

Really the only downside of the above is having to modify the head. If the alloy isn't very weldable it may be a root and the injector spacing can't be 91mm like the MX5 fuel rail so I'd have to get a custom rail made.

Keep the suggestions coming guys, your help is fantastic!

M

Most cast aluminium alloys TIG weld OK, it's the funny alloys that don't (like Dellorto float bowl lids)

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

I like the idea of a CFRP manifold. When I first read this thread, a few months ago, I thought that perhaps you should try a manifold printed on a RepRap machine..? You've already got the thing drawn up, surely it'd be easier to print it than fabricate it. It'd be light, too. And, with the injectors in the head, it'd be a dry manifold, so it shouldn't be degraded by fuel. Pierce should change the casting to throw the injector bosses in - they'd sell even more heads than they're currently shifting, and, given it's just modifying the existing vacuum take-off and adding an extra two of them, not too hard for them to do.

And you've got the wrong link for the tapered injector bosses.

Works juuuuust fine on a CBR600

Great thread Mokesta, intrested to see how this works out

I once saw someone injecting the fuel against the airflow instead of with it. It gave better results that way.

Check out the injectors on F1 engines. They sit about 20 - 50 mm above the inlet trumpet in the centre of the air stream and rely on the huge air velocity to capture all of the fuel. Like this







Someone has used the same idea to add extra fuel for a Honda engine




I think that what these show is that the actual position of the injectors and inlet runners on your head is less important than making the whole package fit. If you can make it fit whilst still getting top performance, all the better.

So you could have short runners with the injectors and fuel rail inside the plenum. Beware of the potential for leaky injectors causing the plenum to fill with petrol and maybe access for maintenance. If you did this, there would be zero mods to the head itself.

cheers
michael

_________________
the world is a book, and those who do not travel read only a page
66 Mini Minor sponsored by http://www.lifeonthehedge.com.au/ The Dog Harness Specialists
It was a pleasure ausmini. I'll miss all you misfits and reprobates

having been through this process I'd advise the easiest thing to do would be get hold of a set of early GSXR 600 throttle bodies, (K1,2 or3) they can be had off ebay for not much and will come with the injectors and fuel rail, you will need to do a bit of respacing, but this is fairly minor compared with building a plenum from scratch.

But that takes all the fun and satisfaction out of designing and building from scratch

_________________
the world is a book, and those who do not travel read only a page
66 Mini Minor sponsored by http://www.lifeonthehedge.com.au/ The Dog Harness Specialists
It was a pleasure ausmini. I'll miss all you misfits and reprobates

Mickmini,,, i "think" (not positive, just think) that the 2x sets of honda injectors in your picy are set-up to phase in & out of the close ones & the long ones to help with the different engine charateristics with regards to ""low down"" & then to ""up top"" rev differences,,, if you know what i mean?

did i say that with any sense at all???

ah i`m getting to old for this sh!t

ah well,,, at least i know what i meant

& mini13,,, i`m pretty sure Mark (mokestar) is sorting it specifically to use a single throttle body rather than quads,,, don`t get me wrong tho, i like quads & i think the """ripping them straight off a bike""" thing is the way to go,,, but in a round-nose mini there really isn`t much room for a decently long enough induction passage, especially with quads fitted bang-on the front of the head

Marks idea leave heaps of room for adding forced induction really easy too

the injector angle really isn`t that critical as far as i have learnt,,, obviosuly there are piles of "rules of thumb" for all sorts of differing situations, but i`ve seen some pretty funky set-ups & angles & all seem to work well enough

the Metro 6R4 set-up with injectors way outside the bell-mouths work really really well for high revs (ala: F1 & GP bikes etc),,, but usually the injectors close to the valve work well for road use & good for economy splashing directly onto the back of the hot valves too,,, so it`s just another case of "Horses for courses" really,,, & in this case i reckon it`s purely a matter of just getting the dam things "Somewhere" at least """in there""" to fit , to start with & go from there ,,, yeah???

_________________
No offence intended here but--> anyone writing a book about minis 30 years ago may not have experienced such worn or stuffed-with components as we are finding these days.

You should put your heart & soul into everything you do.

Cool discussion guys. I haven't made much progress recently as I have been Daddy Daycare for a couple of weeks and been out accumulating parts for my projects.

Further work showed that the injectors in the head thing still has the fuel rail clashing with the bonnet unless short injectors are used. So I may as well leave the head stock and put the injectors in the manifold.

I love the idea of using a rapid prototype system to make the manifold but I am really trying to do this on a shoe string budget. The aim is for the entire EFI setup to be less than $1000. This is a real struggle when new injectors are $70 to $120 each and a custom fuel rail is several hundred.

I have purchased the alloy tube mandrel bends and they come with really long ends so that removes at least on set of welds which will reduce fabrication time. I am just investigating methods of creating the 20 degree bends in the tubes without them deforming and ways of creating bell mouths without buying them at $44 each. A mate of mine made his own steel press tool and pressed bell mouths in a shop press. I may just copy his tooling.

Looking at the 1.5" tube I am using for runners I really think they are too large for the total power I am likely to get and may not provide enough inertia charging at low reves to give good torque even with an effective length of over 200mm. The problem is the smaller tube has such tight bend radius it defeats the purpose. I'll see how this one goes and maybe make another some other time.

I got one of these: http://www.ebay.com.au/itm/3PCE-Muffler ... 519d225f6e which will enable easier tube joins.

I am back at work after many weeks off so my time to work on this stuff is really limited. I'll try to make progress when I can.

M

Yeah, two lots of "standard" injectors means that you can run on the close in ones down low when on the small lobes of the VTEC cam and move on to more fuel coming in from the top ones when on the big VTEC lobes. Nice idea really.

It could also be that the frequency response characteristics of the injectors was reaching limits when it gets up towards 10000rpm. Would have to look into that though. Not really relevant for Mokestas application.

_________________
the world is a book, and those who do not travel read only a page
66 Mini Minor sponsored by http://www.lifeonthehedge.com.au/ The Dog Harness Specialists
It was a pleasure ausmini. I'll miss all you misfits and reprobates

Mark,

I am contemplating buying a running mini when I get back (as a daily driver) so have been looking into the cylinder head you've bought and how i could also turbo charge it. I like what you are proposing so went and did some research.

Firstly I thought surely the vendor would know of a way its been solved?

Then I thought maybe they sell a "plenum" that

A) bolts up to the twin dcoe set up on one face and on the other face, facilitates a plenum that a single throttle body can bolt up to

b) Houses the injectors.

Then I thought it couldn't be that hard/expensive to make, if they didn't. So I went looking. Turns out most COTS "manifolds" are to convert to DCOE rather than "from" DCOE configuration to something else.

I figured all you would need is a "spacer" that is thick enough to set your injectors in to bolt a plenum to.

It wouldn't be that dissimilar to what you have posted in another thread.



It wouldn't need to be a manifold, just a plate where the ports are matched, the holes match the bolt pattern of the double dcoe configuration and has a flat mountin surface to which you would mount this...

Note how the plenum is in two parts...



http://www.xcessivemanufacturing.com/ONLINESTORE.html?pid=87&step=4

What I would do is seek out a SR20 plenum (they bolt together and are single throttle bodied) and get a sheet of aluminium thick enough to mount your injectors in and the bolt the plenum to it. Make sure its airtight

If you get it right, make two.

_________________
But he's thriving and striving and hugging the turns.

Thanks for the ideas JC, I will have a good look at the SR20 manifolds.

I have just commenced on a new project at work, changed offices (Toowong), new team and going up a very steep learning curve. I'll also be travelling regularly to sunny Mt Isa for the next 13 months or so. All this means that progress on my car projects will be super slow again this year.

Maybe the manifold will be built before you get home but probably not...

The upside is my mortgage is going down nicely.

M