Technical Discussion: Ardun Style Heads For a Cadillac Flathead

Designing a set of 3D heads is difficult (you really need to understand 3D CAD, head design, ports, flow, available parts, etc) - but you also need to understand casting, casting shrinkage, CNC machining, tool/die work, fixturing, etc.. There is a lot to know to do this correctly, which is why you don't just see a bunch of new 'OHV' heads showing up for our beloved antique motors.

Then, you get into all the parts that go into them --> rockers, rocker stands, rocker shafts, valves (no problem), springs, etc.. Then you have manifolds to think about. The only feasible way to do this for a very limited production is to use parts that are readily available - so you can take advantage of the work already done.

For a pushrod-job small bore engine, you pretty much need to go to a Hemi design it is about the only way to get enough valve/port size to flow. Obviously a 4-valve head is a possibility - but it pretty much needs to be an overhead cam setup and then you're into cubic dollars.

For a flathead Ford or Cadillac design, I'd be looking to use rocker arms from something like an early Hemi in my design -- could probably make them work with custom rocker stands.

Anyway, enough of my babble . . .

 

Good points Dale.

As for casting, shrinkage, etc., not a problem! One-offs are so expensive, I'm going to go the George Miller, two piece head route!

Haha, funny you should ask, Duane. What kind of intake and carbs do you think? 2x4? Mechanical injection? 3.53'" bore X 4.1" stroke

I'm thinking:

XXO/VGCC- 159.574 mph

XXO/VGALT- 158.422 mph

Then, back to the blower, of course!

 

Ken Austin said he would cast the manifold for me.

 

And what price did he quote yah?

 

I'll post some pictures of rockers to ponder later on today . . .

 

Dale, I was thinking the same thing.When I was at Randy's last week, he has a lot of Hemi stuff, so I was able to look at it and study it in depth.

I've got 3 241/270 heads coming. One is for cutting up, and the other two are for the valvetrains.

So don't cut up that Lasalle block- we're gonna need it!

 

Here is a chronological build to where i am.


http://clubhotrod.com/forums/showthread.php?t=46063

 

Have you REALLY checked Lncoln V-12 dimensions against the V-8 60? Bore centers?

 

Yes

 

Have you? Or are you just throwing some negative BS to see if it sticks? I have long been an admirer of Kens' (32 for Me) work and i have a great deal of respect for what he envisions and fabricates and your negativism is probably why he doesn't post here often.

 

Thank you Oj for the kind words. I don't think this board would really like What I build. I just made a set of '32 rails out of stainless steel for this project that the V12 is going into. I don't think very many would appreciate the work involved in it. But I always wanted a show truck. So that's why I chose to build this motor.
Ken

 

I have been thinking of going with solenoid operated valves. No camshaft would be needed. This will cut down on the friction. Timing will be done with a trigger mechanism on the crank shaft. I have not solved all of the problems and still just thinking.

 

I was asking a legit question. No negativism was implied. I've seen several posts on this site and others where the assumption was made that the Zephyr engine was the same as a V-8 60 with 4 more cylinders. I know the bore size is not the same.

 

I don't get to look at the pictures because I'm not a member. But if Don is working on this it should turn out good. #2 or #3? If someone here has spare time to waste, I was wondering about Cad drawings such as I see in this thread. Are these step necessary to machining billet heads? Of just a concept drawing that was made by a machine? I once made a drawing of a 455 Pontiac head gasket for a dry deck engine. This was so the owner of a CNC punch press could program his machine to punch out gaskets from a sheet of copper. It was just a pencil and paper full scale drawing with all dimensions coming from a hypothetical datum point off the gasket surface. I did what I was told to do. Never had anything like one of these CAD drawings. Could somebody PM me with a short explanation of the purpose of these drawings/ Thank you. V4GMR@yahoo.com

 

sadly 32, you cannot see the pictures unless you are a member

 

Rich,
It's simple- it's so we can get them built!

You didn't/don't need the drawings, because you're a helluva machinist, and were able to do your own work.

Most of us, myself included, are not. Because I have not been able to find a machinist willing to work with me on his, I have to hire one. The only way the machinist here will do the job, is if I supply CAD drawings.

The CAD drawing insure each head is exactly like the other one. I realize, with what you did, and I'm doing, this is not so critical as to kill the build, but it does help.

IF I had a machinist that was interested in working to make these, or had your talent and equipment, I would do exactly as you did, and not do the CAD drawings.

 

Rich,
The drawings are all done on the computer to lay out the ports, water jackets, bolt holes and chambers. These programs are so sophisticacatd now you can see any interference as you are drawing. Once everything looks good I send it out and have it made out of plastic (stereolithography) now I can actually hold the part and bolt it on for a final check. If everything is good the program is written and sent to my cnc mill. And that's all there is to it.
Ken

 

No way - lots of folks would be interested! Langy is on here with a stainless chassis T project. Plenty of love for show car style projects.

 

Here it is


http://clubhotrod.com/forums/showthread.php?t=46063

 

Ken has explained the basics -- having a completely accurate and to-scale 3D model makes it possible to generate CNC toolpaths/code such that you can machine a chunk of aluminum to exactly match each side of a clam-shell billet head. The accuracy of the final product is dependent on the accuracy of the original design -- and the quality of the machine, tooling and CNC code generated from it.

As you're going to be making a CNC generated head, another prototype method is to just cut prototype material in the CNC -- exactly as you would aluminum. Then you can take the prototype material and try it on the block, use it on a flowbench for testing, etc.. Once you're happy with the final design and have done the prototype validation, then you generate your final CNC toolpaths and cut real material. The goal is to NOT waste a $150 piece of 6061 material -- trying to get your 3D models and CNC toolpaths, fixturing, bolt-holes, etc - exactly right, you use cheap and easy prototype material before you cut any real material. This is how we've done it with the FlatCAD models.

Also, you can generate a 2D section of the deck surface and cut what looks like a 'gasket' out of thin plex like material (on a laser cutter). We use this prototype deck surface to validate the position of all bolt holes, bore centerlines, water jackets, etc.. Makes it real easy to just bolt it to the deck and visually validate everything -- again, before we cut any real 6061 material.

You'll find that these vintage blocks are not 100% the same from one bore to the next or from one bank of cylinders to the next - so you need to 'tweak' locations of things to get it right. All the original patterns for these blocks were done by hand, so it is amazing they are as close as they are . . . but you have to 'adjust' your CAD models to fit the actual piece.

Hope this helps!

B&S

 

Dale, you're right and i have a great deal of respect for your opinions and input. I just made a knee-jerk reaction, sorry about that. oj

 

Much better explanation than mine. I do the same thing in the beginning just for a first look. If you look at the drawings I posted earlier, there is one that looks like a head gasket. It is exactly what he explained. That is laser cut out of 1/8" material to check both sides. My block was close enough to continue with out making any adjustments.
Ken

 

OH, well. That is informative to me. I thought it was a gasket. I appreciate the effort to help me understand CNC. My last few years at the Airline I had a couple of guys working for me running CNC grinders. But nobody would let me get near to them. Maybe it was for the best.

 

All this thinking reminded me that I did run a Computer controlled mill some years ago. The 60s. A Bridgeport with a MOOG controller. More of a Monkey see, Monkey do, deal. I once was sent off to Le Blond Makino to advise the company on a $5,000,000 purchase of a new machining center. Guys were in my group who wrote programs for CMMs and CNCs. But when I would ask them how it works, they would say "Good" Nobody would explain the laser measuring machine either. How can it be possible to measure the difference in the amount of time it takes a light beam to travel 4.500 and 4.501?

 

Gentlemen, I do believe it's time for a build thread!

 

Given what I've since learned about Ken, I should not have raised the question. Sorta like doubting Duntov. I'm the one who should be apologizing.

 

The one item I can't come up with is a reasonable way to get the oil from the head, back into the block.

How do they do it on Arduns? Drill return passages through the block?

Getting oil to the head is no problem, as I can plumb in lines off of the dry sump.

 

Ardun heads have a trough that gathers oil at the bottom of the head and a tapped pipe thread for an external fitting. There is an external line from the head to the oil-pan. Usually there are also lines from the new exhaust port block-off plates that go to the same drain line . . . back to the pan.

So some of you are thinking . . . WTF? . . . why would they drain oil from the no longer used exhaust ports back to the pan? What the hell is that all about

Reason: As you now have push-rods going through the original guide passages (with no valve guides in them) and you need a fairly large push-rod hole, oil will run down the push-rod and go into the ports. On the intake side - no problem, it just drains into the valley - the exhaust, however, would fill up with oil if you didn't have a drain back to the pan from the outside block-off plates.

 

External drains, no problem.

 

As an example here is the oil return on my Dodge except it is from the intake runner. (One omly on the Dodge)