The 230 Headerfold project

[monkeymissile]

That certainly would be handy.

that's what I thought too. I'd rather fuss with the valve on cold days from inside my unheated cab.....

[maineSS]

I found some specs for later 230's on the AllPar site- 120 hp and 202 lb/ft torque at 1600 rpm, compared with my 1949's 95 hp and 185 lb/ft at 1200 rpm. This is a 21% increase in hp and a 9% increase in torque- since they used the same intake/exhaust mainifold and carb, something had to change. There was a compression ratio increase from 6.7 to 7.9:1, but this wouldn't account for that much increase.
In an earlier thread, one person mentioned using a split exhaust with better flowing intake manifold to go from 45 RwHP to 65 on a chassis dyno. I also contacted the owner of headerdesign.com, who told me that the 3-2-1 type header is classified as an "interference" header- it cancels wave activity in favor of restriction reduction, and gives a smooth low-midrange powerband. He also said that the stroke & hp figures would have to be changed to use the program- basically up the HP and incrementally reduce stroke and add the increment to the bore until it works. Regarding the split design, his opinion was that combining into one exhaust pipe would yield more power than dual, but duals would give a unique tone preferred by some, and the HP difference would not be large. This seems to agree with the Pontiac OH6 site, and also explains why the commercially available Tri-Y's are split 2 into 1's. Sounds like your fabrication job just got easier!

[monkeymissile]

dual

I found some specs for later 230's on the AllPar site- 120 hp and 202 lb/ft torque at 1600 rpm, compared with my 1949's 95 hp and 185 lb/ft at 1200 rpm. This is a 21% increase in hp and a 9% increase in torque- since they used the same intake/exhaust mainifold and carb, something had to change. There was a compression ratio increase from 6.7 to 7.9:1, but this wouldn't account for that much increase.
In an earlier thread, one person mentioned using a split exhaust with better flowing intake manifold to go from 45 RwHP to 65 on a chassis dyno. I also contacted the owner of headerdesign.com, who told me that the 3-2-1 type header is classified as an "interference" header- it cancels wave activity in favor of restriction reduction, and gives a smooth low-midrange powerband. He also said that the stroke & hp figures would have to be changed to use the program- basically up the HP and incrementally reduce stroke and add the increment to the bore until it works. Regarding the split design, his opinion was that combining into one exhaust pipe would yield more power than dual, but duals would give a unique tone preferred by some, and the HP difference would not be large. This seems to agree with the Pontiac OH6 site, and also explains why the commercially available Tri-Y's are split 2 into 1's. Sounds like your fabrication job just got easier!

mSS,
I hadn't ever really considered a dual exhaust design. I just figured there wasn't enough space anyway. I have a brand new 2" exhaust pipe that was meant to go from stock manifold to stock muffler and I'd like to try to still use that. I did get a glasspacked muffler though because it was so cheap.
Therefore it looks like I'll have 1 3/8" primaries merging into a 2 1/2" collector then into the 2" stock pipe and finally through a 1 3/4" muffler. All told system length should be 81-83" long. I hope to work on the model again this weekend.

[monkeymissile]

other DIYers....

http://www.moparchat.com/forums/arch...hp?t-2136.html

Many mention Headers By Ed, but not sure if he's around anymore...

[monkeymissile]

another one

http://www.carcraft.com/techarticles...ers/index.html

[Sickcall]

I used the stainless magnaflow single exhaust off the header on my 251. its a stock looking round straight through design. I have had more compliments on the mellow tone.

[monkeymissile]

I used the stainless magnaflow single exhaust off the header on my 251. its a stock looking round straight through design. I have had more compliments on the mellow tone.

Sickie,
what's the inner diameter of your magnaflow?

[monkeymissile]

flexible paper tubing?

several sites referenced this product that was used to mock up the complicated primary pipe shapes when building headers. I googled it to no avail. Anyone have any idea what this stuff is and where to get it?
I suppose I could use wire to approximate the pipes, but something the correct diameter would be much more accurate. Thanks!

[MoparNorm]

If you're going to do this seriously, you'll need to make a jig so that every set is identical and a perfect fit.
You can only make a jig from a full sized set, so you may as well bite the bullet and buy the real tubing and start test fitting your prototype set.
This is the Poly Header prototype, in a WDX:

[monkeymissile]

prototype

If you're going to do this seriously, you'll need to make a jig so that every set is identical and a perfect fit.
You can only make a jig from a full sized set, so you may as well bite the bullet and buy the real tubing and start test fitting your prototype set.
This is the Poly Header prototype, in a WDX:

Norm,
I hear you and if younger I'd probably jump right into this, but with limited time+resources I feel more comfortable making a pre-prototype before I start cutting tubing. Considering that I want all primaries to be the same length, but don't know what that length is yet, I was thinking that 1 1/4" foam backer rod with some 3/32" or 1/8" welding rod down the middle would make cheap and reasonable approximations of my final pipes. Then once I figure out where all 6 pipes go I can start cutting and tacking steel, building one pipe at a time and still have the other foam pipes in place to check fit.
Then I'd build my production jig once the first full set was tacked up.

Question for you since you've done this before: How did you replicate all the various lengths+cuts of pipe required for each primary when you went into production? Were all the parts numbered/cataloged and then mass produced to be welded up when needed?
Your prototype pic is great. I am considering making a simple expanding tube-end tool to make slip-fits for easier welding.
Do you have any pics of the production jig you could send me?

Thanks

[Clint Dixon]

By "jig" I assume you mean tooling?

If you're going to do this seriously, you'll need to make a jig so that every set is identical and a perfect fit.
You can only make a jig from a full sized set, so you may as well bite the bullet and buy the real tubing and start test fitting your prototype set.
This is the Poly Header prototype, in a WDX:

Tooling is commonly built around an existing product in a 3D design environment. Tooling typically locates all components of the product in respect to their individual three established datums with shimability in the three respective directions. Tooling also commonly has manual, pneumatic, and/or hydraulic clamping capability. It may also have an eject system to remove the finished product from the tooling. Product can become locked in the tooling due to twisting and general movement of parts because of the introduced heat from the welding process. Well designed tooling can be adjusted to compensate for the anticipated and resulting twisting.

In using computer 3D CAD software package the process of steps might be such:

1) Reverse engineer the engine block and create a 3D model
2) Reverse engineer any other peripherals that the headers must fit around and create 3D models of same
3) Design and model header components and assembly as a product
4) Combine product and peripherals together in a 3D assembly to determine design fit, style, shape, and function
5) Run FEA analysis on 3D product to determine strength, effects of welding, effects of exhaust heat, etc.
6) Create Engineering drawings of product from design
6) Build plastic, wood, paper, etc. prototype model from Engineering Drawings and test for fit on actual vehicle
7) Design tooling around 3D product to assure that each product produced is the same as the one before it and the one after it.
7) Create Engineering drawings of tooling design
8) Build tooling from Engineering drawings
9) Build product utilizing tooling

Of course, these steps and this level of effort is not necessarily needed on a project such as this, but this is a graphic representation of why we find only a limited number of Power-Wagon parts being created or reproduced.

[monkeymissile]

Clint,
sounds like you have some experience with the process, excellent!
Perhaps I should've been more specific. I typically call a device designed to hold a part(s) for machining or welding a jig and tooling more like punches, dies, molds and the actual cutting tools in the case of lathes and mills. At least that's what we called them where I worked. At any rate, I believe we're talking about the same thing!
I am also well down the reverse engineering road. I have a 3D CAD model started and so far modeling the block, oil+fuel pumps and intake manifold has been easy. The tricky part is modeling the actual primaries because they need to change direction so often. I am still relatively new to the world of NURBS modeling so it's been a big learing curve. I hope I don't have to switch CAD applications if mine can't hack it!
That's why I thought my flexible foam rod idea might be faster and get me to the same place in the end. It all depends; I'll have way more computer time this winter than hands-on truck time......
FEA would be sweet indeed. Oddly enough I used to work for an outfit that did FEA, but they've since gone under.

[MoparNorm]

Norm,
I hear you and if younger I'd probably jump right into this, but with limited time+resources I feel more comfortable making a pre-prototype before I start cutting tubing. Considering that I want all primaries to be the same length, but don't know what that length is yet, I was thinking that 1 1/4" foam backer rod with some 3/32" or 1/8" welding rod down the middle would make cheap and reasonable approximations of my final pipes. Then once I figure out where all 6 pipes go I can start cutting and tacking steel, building one pipe at a time and still have the other foam pipes in place to check fit.
Then I'd build my production jig once the first full set was tacked up.

Question for you since you've done this before: How did you replicate all the various lengths+cuts of pipe required for each primary when you went into production? Were all the parts numbered/cataloged and then mass produced to be welded up when needed?
Your prototype pic is great. I am considering making a simple expanding tube-end tool to make slip-fits for easier welding.
Do you have any pics of the production jig you could send me?

Thanks

We ran all of the parts in lots for 50 sets. I don't have photos, those belong to the fabricator and are in his shop.
We actually shipped that prototype back and forth between us, 4 times... so I could test fit the various trucks that fit the same set.....= )
They actually fit 11 different truck types, it wasn't easy...= )

[maineSS]

What size were you planning to use for your intermediate primary (I assume you're thinking Tri-Y)- the one that receives input from 3 cyl and merges with the collector? Your original concept was quite close to the commercially available interference type Tri-Y's- some adjustment of that should be all that's needed.

[monkeymissile]

We ran all of the parts in lots for 50 sets. I don't have photos, those belong to the fabricator and are in his shop.
We actually shipped that prototype back and forth between us, 4 times... so I could test fit the various trucks that fit the same set.....= )
They actually fit 11 different truck types, it wasn't easy...= )

I would think that with them fitting 11 trucks you'd have no problem selling them all!
Did you ever go see your headers being made?