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Any news on these?

Happy new year!

Still working on the 3d cad file. It's the most important part of the job and the most time consuming plus we're not paying fastlane money so can't get the whip out

Might be worth sending the resulting file through a "3D printer" and making a few investment castings for verification...

Seem like complex castings like aircooled heads (fins etc) would be an ideal use for one of those setups.
(This may be a normal verification step these days for all I know about production casting)

Those are getting cheap to the point where they are affordable...
...related thought--- How good are those 3D scanners? Those have been around for ages.

There is even a "Free" DIY 3D printer design out there from MIT IIRC. Prints wax, even chocolate
(If I had a proper shop I'd probably have one already)

http://video.popularmechanics.com/servi ... 1231030451
(The machine can be FAR more accurate/capable than what is shown in the video... Although that "texture" might work really well on intake ports)

If the printers were to get fast/cheap enough, it might be cost effective for production, esp since you can print the head in wax/plastic to quite excellent accuracy, as well as the fact that an investment casting is typically VERY close to finished product...

Watching the commercial machines run is alsost like magic, at least to this hardware geek.

Please, PLEASE don't forget the meat for the dual plugs etc...
Shelling out a mortgage payment for the required welding etc on a stock casting is not on my short list.

I vaugely recall stoning the Apfelbeck head team awhile back on this subject... Apologies if this is redundant, you might be involved with that too?

I thought about the whole rapid prototyping thing with some manifolds recently and decided not to bother with the process.Some people suggested that it would be better to go sand cast first and progress to die once the product was proven, I didn't bother with that either just winged it straight to die and it was very successfull luckily. The beauty of modern 3d cad is the files can be loaded straight into CNC milling machines so the part can be proved by machining the head completely from a lump of ally. More expensive than a wax or resin model but it produces a useable part rather than a souvenir for the mantlepiece.

Can you mark on a pic where you would want this extra plug as I can't see anywhere practical to put it -the exhaust ports and pushrod tubes are in the way big time

I would STRONGLY suggest consulting HAM and Jake on this...
(preferably working with, I sorta assumed you might be already, as it would be in all your best interests)

HAM apparently DESPISES the welding work involved to dual plug heads, ... and Jake LOVES the way the dual plugs work, so HAM is an unhappy camper

I'm pretty sure both of them would love to get their hands on a different source of castings vs the AMCs, esp with the described features.

AFAIK they use an 8-10mm 19mm reach plug, NGK makes some, there is also a 13mm reach one in 10mm.

Your castings, as described (or at least as my highly optimistic eyes read this thread) could cut the cost of REALLY high end T4 heads by 60-70%, by eliminating most if not ALL of the (extensive) welding/heat treating steps required on the AMC or stock castings.

The cost of a 50x40 head with ~ CE flow numbers would not have to be appreciably more than std, as 50mm valves/seats cost ~the same as 35mm valves and seats, and the CNC costs would be manageable, as it gets loaded in the mcahine regardless. (The "touch" cost woudl be the same)

(Note---The 60-70% number is pulled directly out of my arse, but is likely reasonable)

I had a nice little "conspiracy theory" going in the amusement park of my mind after a comment attributed to DRD re:T4 heads in another thread... Reminded me to ask here...
Perhaps DRD et al are considering working the bare QSC Chinese castings...

You can get a reasonable RP machine for ~ $5K these days.
(Probably far less if you DIY, and the MIT design "scales")

There are (top end) RP machines that can make near finished parts out of ~ANY material, using powdered metal and laser/s.
(Done under vacuum or argon, NOT DIY, yet)

Just always remember... You can make "impossible" to cast parts in an RP machine (or PE for that matter)

You have to finish the cycle, which is why making the part in wax and investment casting is suggested.

As the plan goes the casting will accept type 1 or type 4 exhaust ports,the intake flange will accept ports larger than CE, and the only place that a 2nd plug can go will be left solid.The secret to this job ( trying to please everyone ) is being able to produce all the variants from the same die.There will be different sand cores for the different ports and different machine programs for different options-small batch runs -this is what the chinese can't do !

Here's a pic of the new type 4 manifold-the left port has had some material added to the flange and the port shown is quite a bit bigger than the CE.The right port has standard flange profile and you can see how much the thicker wall is protruding beyond it.This manifold has had the flange angles tweeked to get rid of the horrible dogleg I've seen on some aftermarket stuff and also allows inboard injectors firing straight into the port. 50 to 100 more hours of design to go into this before production
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Nice!
But why use the 3-studs in the middle? I assume your manifolds are meant for your heads solely?
If not, pls take into account that the 914-3-stud outer studs are a little but more inboard iirc than on a 4-stud head. In any way, the outer studs on a 3 or 4-bolt head are not placed exactly the same...

I think I took the bolt pattern from a 914 head I have here and added the extra 2 holes so I will check a bus head for the correct pattern thanks for the info. I had to draw the flange so I could tweak it around and check wall thicknesses,port sizes etc.The flange can then be placed into the head and extruded through to the chamber roof.The manifolds will fit any T4 head hopefully

A 4 stud head has the holes quite a lot further in.

I had to clearance a 914 3 stud injection manifold to even be able to use a 11mm nut (as well as slotting the hole)

The 11mm OD allen head exhaust barrel nuts work pretty well in super "tight" spots.
(CB sells some for exhausts, but the nuts don't care where you use them ;-0 )

Inboard injectors can be nice from a packaging standpoint, but if a LITTLE meat could be left on the outside, a simple injector boss could be drilled/tapped/ screwed in the right place for folks that can use it. (Like anything other than an uncut T1)
Injectors want to be aimed at the valves... Not the port wall.

If inboards are a must, I'd put them as close to the TBs as possible.


Just making more work for you, Paul

I'm highly dubious you'll be able to make a "universal" manifold unless you do a square int port on the "big" heads and CNC off the delta. Barrel nuts will help.

It's not a problem casting bosses into the back of the manifold if you want that-but as you say forget type 1 and also early Bay Windows . I don't think it's a problem hitting the port wall as most people run batch fire injection and even if the fuel sprays right at the back of the valve if the valve is shut then it ends up in the port.
I'll draw up a bus head stud pattern and stick the holes in see what it looks like or maybe just make a whole new flange pattern so you have to buy my manifolds and make the top pattern 85mm between bores so you can't fit carbs

The intake valve gets hotter than you might think, helps fuel atomization/evaporation/mixture quality greatly under anything but WOT conditions, and helps some even then. (This is why ~all OEM injectors are aimed like that)

I completely sympathize why one might want a inboard injector for packaging reasons.

Also consider quite long studs can be installed.. Clearance for those takes little room, and gets the nuts out where they aren't an issue.

Paul H wrote: I don't think it's a problem hitting the port wall as most people run batch fire injection and even if the fuel sprays right at the back of the valve if the valve is shut then it ends up in the port.

The inboard mounting of injectors has NO measurable meaning in drivability, mpg or torque in practice. So, Ill agree with the above.

Pile, I have shown you my results of this in a few threads (my 2056cc engine for instance), yet you still keep saying its a problem I have driven with the injectors on both sides (did you?) as the Ahnendorp manifolds already make this a possibility for some 20 years now... I'll obviously just have to say it again: IT DOESN'T MATTER!
You are writing purely from a theoretical point of view on this is my observation, which is often just fine, but it keeps these stupid myths going and going.

Paul, just make them like you intended, it'll just work fine and fit to boot

Inboard mounting of the injectors is the best place to put them and allows a free hand in throttle body design. The only down side to high mount injectors is that wet manifold walls make transient tuning more difficult but it's all hair splitting if anyone is that bothered then there's no point discussing the subject unless you run sequential.Although some recent testing we did of a manifold with outboard injectors firing straight at the valve showed it made it's peak power at a leaner mixture strength up around 13.9 instead of usual 12.9 -13.2.
Anyway I'll have another pic of the manifold later with outboard injector bosses and the bus stud pattern

Here's the latest version with outboard injector boss and stud pattern for bus.
The hole for the bus head is 12mm diameter for a barrel nut and cuts right through the wall. The tract on the casting will be a lot smaller so it will probably go with some die grinding and if you want a massive port on a std head then you are in for some serious welding and grinding anyway.
What do you think of the raised pads on the flange to make access easier?