Designing a new Early Hemi Single Plane Intake!

[BOSSMAN]

Well my dream has come true! I have been asked to make a modern single plane intake manifold for the Early Hemi. Single plane manifolds are basically non existent for this motor and with the popularity growing on these particular motors there is certainly a need for something like this. Luckily with our EMC effort I have been cooking up a plan for a few years and now it gets to go into action!

Just thought it would be cool to share some of the process with you guys cause it is a TON of work to do. Gene Adams will be building a motor for us to test with and see how well what I come up with works! If all goes well it will be getting casted at a foundry after the core boxes are made.

To start with, it took a long time to find a good casting to base this off of and after many attempts I found one I can make work. Its not very easy to find one that has a close enough bore spacing let alone similar bank offset. Its a kick ass piece to start off with!

Nice high runner entry and added plenum volume.

Then the fun begins - removing some of the flange pieces.

Note to self: Buy yourself a Vertical Metal Band Saw!

Time to start reshaping the raw unmachined casting.

Smoothed out the exterior to remove any casting flaws. I will bead blast when finished.

Only have a few more things to touch up.


New flanges are being machined by a friend who owns a CNC Shop locally to me. Also have another guy who TIG Welds for me ready and waiting to help weld what I need done. Gene Adam's is sending me a 354 block and some stock heads to be able to mock up everything for proper fitment and before I get to porting on this manifold.

In the meantime I have been crunching some numbers on what I need for a tuned length (3rd Harmonic). With the use of some thick spacers that I need to get to the correct deck height the runner length gets longer. Luckily this is EXACTLY what I need to cater to a broader spectrum of engines. Here is something to get a rough estimate for length.

I will post more as a progress.

[milner351]

Fantastic!

[DanStokes]

Cool that you get to do this. Remember us when you're rich and famous.

Dan

[Monk]

That is good stuff and amazing work.
I'm in awe of guys who can do this.

Just recently a guy up in Canada came up with his version
of a single quad intake for a 409.

[BKBridges]

Nick,
I too like this kind of stuff! Watch out for warpage during the welding process! Our Landcruiser system was a PIA that way. Im sure youve got that side covered. That casting has some serious meat to it!
BKB

[BOSSMAN]

Thanks to Gene Adams and Ron Pratt I now have a Early Hemi!

I set the manifold on to see how things are lining up. It looks like I will not be able to make the flanges as thick as I hoped so I will re-adjust my runner length now that I know what I'm dealing with.


Here is the Intake Face angle difference. My next move will be to correct this angle to get ready for new flanges.

The port alignment from bank to bank didn't line up like I had hoped so it looks like I will need to quarter the manifold to move things where they need to be. Time to get creative!

[BOSSMAN]

Well, made some more progress today on this manifold. The goal today was to mill the correct face angle into the manifold to work on the Hemi. It was about a 3 hour process making chips but got this portion done for now.






I was taking .100 off at a shot for awhile but then backed down to .050 once I started cutting more of the surface. Here is a little clip of the face mill in action taking .050 off. http://youtu.be/nYyFDCq2pGc

Luckily everything lined up pretty well on the first go, damn near perfect and luckily I remembered to write down the head tilt angle number and my setup.


This pic is showing port alignment which is about where I want to end up. I still need to mill more off of the runners to compensate for flange thickness but how it is located now will give room for Raised Port Racing Heads.

[TC]

Crazy Crazy Nick, look good!!!.....

[Beagle]

I was wondering about this yesterday - and I'm still confused as hell about the port alignment. Is intentional?

[BOSSMAN]

I was wondering about this yesterday - and I'm still confused as hell about the port alignment. Is intentional?

So there are a few things: Getting the port to align properly height wise to have enough material in the right places to work for a wide range of port sizes from a stock head to a full on race head. Another is the spacing from port to port or bore spacing difference which is making the port centerline the same from cylinder to cylinder on the same bank. The last thing that is effecting what I'm doing is Bank Offset meaning how far ahead is the #1 cylinder to the #2 cylinder. The manifold that I'm using differs not only in bore spacing but also bank offset. It is the closet thing I could find without starting from scratch. As I make progress you will understand more. My goal for today is to find a vertical band saw large enough in town to quarter the manifold. I need to stretch it to correct my bank offset issue and then will fill with material in between before it gets welded back together.

[DirtyWhiteBoy]

What a cool project! Is this for a Chrysler tall deck?

When I started my low deck Desoto, I had no idea what a hassle it was going to be. I thought the Dodge, Desoto, and Chrysler Hemi parts would interchange. Oh well it's only time and money right? It will be worth it in the end.

[milner351]

Fantastic work Nick - more proof that NOTHING is impossible given the proper talent, motivation, and machines.

[BOSSMAN]

What a cool project! Is this for a Chrysler tall deck?

When I started my low deck Desoto, I had no idea what a hassle it was going to be. I thought the Dodge, Desoto, and Chrysler Hemi parts would interchange. Oh well it's only time and money right? It will be worth it in the end.

Yes, I believe the deck height is just shy of 10.4 (10.390?). With the added height I was hoping the heads were spread apart further to be able to add some runner length but no go. I'm still within my target range on length luckily.

[BOSSMAN]

Fantastic work Nick - more proof that NOTHING is impossible given the proper talent, motivation, and machines.

Yeah, I'm a little overdue to do something like this. It has been a good learning experience so far since this one is taking alot of planning. It's much different than the EMC Hemi Hilborn setup but still alot of fun to see come together. When there is a will there is a way!

[Beagle]

"...The manifold that I'm using differs not only in bore spacing but also bank offset."

that's what I missed. You're gonna cut the hell out of it, just figured it out. I'm a little slow. haha.

Thanks for clearing it up.