Mopar M1 Manifold Injector Bosses, Not Drilled Out

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Dodge74

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I have a Mopar M1 intake that has what appears to be injector bosses. Can they be drilled out by me or do I have to take it to a machine shop? I would like to use it on my Magnum build. Any help would be greatly appreciated.

Thanks
20170304_152341.jpg
 
I do believe that those are for nitrous, and aren't big enough for efi.
 
Thank you guys for the input but still don't know what to do with the intake maybe take it to machine shop I don't know.
 
I knew it.. I thought that's what those were now all's I need is someone who can drill these out for me any suggestions anybody

Again thanks for all the help Fabo
 
Hopefully I can find a machinist here in town that is able to drill these out I really do not want to drop $600 on the Hughes Unit...
 
Its just an EFI step bit and a drill press. you can do it. Its not needed to be CNC accurate as the injectors float on O-rings and can tolerate some slop. The O-ring ID is 14mm and a 17/32 (13.49mm) drill bit can be uses to drill the through hole, then drill that out to 14mm to make a step for the injector to seat into. Dont 14mm drill all the way, just deep enough to make a nice step seat. I did it to some 3/4 OD AL thick wall tubing and made a bunch of injector bungs for my slant head. Someone over on Slantsix was loaning out that bit, but if you had a machine shop buddy, I bet he could chuck a 14mm in a lathe and use a carbide cutter to step down the tip to form a MSD 2160 pocket cutter for less than the $130 they want.
inj_dim.gif
 
ross machine racing makes a drill bit specifically for doing EFI fuel injection bungs. I am going to be doing the same thing with my magnum M1 single plane. will be making a jig to replicate the spray angles and injector spacings from the factory kegger style manifold over to the M1 casting and reuse factory steel fuel rails.
 
I got a contact over on slantsix that MAY lend you THEE step bit for this. PM me.
 
Hypotek is probably the best at drilling them, he knows what hes doing not an amateur hack job. He get $135 which is a pretty good price
 
@frosty_the_punk did you ever get your intake drilled? I’m thinking about drilling my crosswind intake and putting the MPFI back on my 5.9.
Does your Crosswind have injector bosses cast into the manifold? I don't remember seeing injector bosses on thoses, although you can still drill it and weld in some injector bungs.
 
Does your Crosswind have injector bosses cast into the manifold? I don't remember seeing injector bosses on thoses, although you can still drill it and weld in some injector bungs.
It doesn’t. I’d just do like you said and drill it and have bungs welded on.
 
It doesn’t. I’d just do like you said and drill it and have bungs welded on.
ross machine racing makes a drill bit specifically for doing EFI fuel injection bungs

I bought one of the ross drill bits to cut in the EFI bungs into a manifold. Used the same tool to cut the injector ports into the fuel rail. Made a simple fixture for a bridgeport,,worked great, invest a little bit of money, get the right tool and do it right and the EZ way at the same time.

intake injector port machining
 
The Ross tool is just a modified drill bit. It's cool for drilling existing bungs in one step but will not work for 75slant6 to modify his Crosswind. He just needs to order some bungs and drill the holes needed for the bungs with regular drill bits.
Incidentally, the OP could have drilled his existing cast-in bungs with two sizes of drill bits, and a quick chamfer on top. Some manifolds don't even use a stepped hole, just one size for the O-ring.
 
@frosty_the_punk did you ever get your intake drilled? I’m thinking about drilling my crosswind intake and putting the MPFI back on my 5.9.
Unfortunately, there were some setbacks and it's not completed yet. There was a fire in the workshop and it's been under construction for about 12 months.

Re: the bungs, the hard part is done. I have only just recently picked up where i left off.

The injector bungs in the magnum manifold have an opening of 11mm, that is the hole which the injector actually squirts through. An 11mm transfer punch is a firm fit in this hole with no slop at all so can be used as the basis for alignment of the jig during fabrication.

The entire jig bolts onto the face of the manifold where it bolts to the cylinder head.

The 6mm thick top plate with the tubes will be able to be removed/replaced while the manifold is setup on the drillpress. I currently still have it tack welded together since that is the best way to make sure nothing moves while drilling the bolt holes, the bolts will have a countersink to ensure correct alignment upon reassembly.

Using this design I can use the same 11mm transfer punch in the drillpress chuck to align the drillpress with the tubes in the plate and then when everything is aligned I simply remove the top plate and replace the 11mm transfer punch with the "injector bung drill" which I bought from Ross machine racing.

This is the jig as it sits now, it doesn't have to be pretty it just has to work.
The rough looking tabs at the ends are just tacked there for stability, they will be removed.
20180620_221504.jpg
 
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If your manifold doesn't have bosses cast-in, you could use a similar jig for alignment to drill the holes in your manifold's runner, making it ready to weld in a pre-made bung like this one.

Injector Boss - Weld In - Aluminium - Large

You would need to use a large end-mill instead of a drill bit though. And you'd need a kegger manifold to use to make the jig.
 
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