Digitizing Cylinder Heads Help

[Alan Roehrich]

Originally Posted by BRETV

Maybe the new IHRA could implement these techniques during teardown and enforce the rules like they should be. Then winning an Ironman would mean more than winning a Wally. Just an idea.




Bret Velde
2003 I/SA

Unfortunately, like it or not, for the vast majority of Stock, Super Stock, and Comp racers, and probably the .90 Super racers, the NHRA Wally is the Holy Grail, it has been for decades, and it is not likely to change.


I think the new IHRA, as much as we want them to succeed, is going to struggle, and I seriously doubt they're going to have the money or personnel to police class racing. Let's be honest here, you're not likely to find many like Dave Ley, Wesley Roberson, and Travis Miller.



I wish IHRA and my friend Alan Rheinhart the most success possible.

[SSDiv6]

Originally Posted by SBillinson

Joe,

I have a digitizer similar to a renishaw but only 3-axis, which limits port digitizing, especially at the short turn and bore wall side.

I looked at Keyence, but am unclear about which product would work best for port digitizing. Laser, I assume, would provide the best detail, but at what cost?

Having a digitizer that has file extensions compatible with CFD software would be ideal (like Autodesk CFD, not Siemens or something only OEMs can afford). I'm sure it exists, but, again, how much?

Thoughts?

Hope all is well.

Hi Steve,

Doing well, recovering from the RSV and all the ongoing wars have been keeping me extremely busy.

For measuring parts, we purchased two Keyence IM-8000 Image Dimension Measuring System. It paid by itself by reducing the time performing physical inspections and also sampling. We paid around $78K for each machine, includes full support and personnel training by Keyence.
https://www.keyence.com/landing/meas...iAAEgLAifD_BwE

We also purchased the Keyence WM-P6200 Handheld Scanner.

https://www.keyence.com/products/3d-...dels/wm-p6200/

Other great companies with 3D handhelds are Hexagon and FARO.

[GUMP]

Originally Posted by BRETV

Maybe the new IHRA could implement these techniques during teardown and enforce the rules like they should be.

This looks good at first glance, but would be pretty much impossible in practice.

Even if the sanctioning body did aquire virgin examples of every single head in the guide they would run into issues. There are enough variations from casting to casting that a "tolerance" would have to be allowed. If not, lots of untouched heads would fail when compared to the sample. With that allowance, the scan is useless and we are in a similar (but worse) situation than what we have now.

[Kevin Panzino]

Not going to get involved with the side discussions regarding NHRA checking stocker heads with a device, nor the NHRA /IHRA discussion.

But I can tell you from being in industry, the level of detail that the modern laser scanners and/or a 5 axis CNC mounted digitizing probe, and the software that goes with it is at a level that blows your mind. As long as the laser/probe can get to everything, it will create a model of the shape that is within at most .001" and in most cases better than that.

What I always wondered about, is just how repeatable the castings are/core shift etc,

Certainly a major issue on the old factory castings, but just how good are the new approved aftermarket heads on core shift?

I have to think a scanned, max-effort head that someone spent a ton of time on, one port at a time, and checked along the way with a UT device and got to min wall at a few places wouldn't then break into water and create more than a few boat anchors when that program was run on a new head ??

Kp

[Ralph A Powell]

Your question about coreshift depends on how good your tooling is and the pins and bushings on core boxes!

[SSDiv6]

Originally Posted by GUMP

This looks good at first glance, but would be pretty much impossible in practice.

Even if the sanctioning body did aquire virgin examples of every single head in the guide they would run into issues. There are enough variations from casting to casting that a "tolerance" would have to be allowed. If not, lots of untouched heads would fail when compared to the sample. With that allowance, the scan is useless and we are in a similar (but worse) situation than what we have now.

Gump is correct. There will need to be a tolerance percentage allowance due to shrinkage and core shift. Shrinkage can be as high as 6% in Aluminum castings.

[SSDiv6]

Originally Posted by Kevin Panzino

Not going to get involved with the side discussions regarding NHRA checking stocker heads with a device, nor the NHRA /IHRA discussion.

But I can tell you from being in industry, the level of detail that the modern laser scanners and/or a 5 axis CNC mounted digitizing probe, and the software that goes with it is at a level that blows your mind. As long as the laser/probe can get to everything, it will create a model of the shape that is within at most .001" and in most cases better than that.

What I always wondered about, is just how repeatable the castings are/core shift etc,

Certainly a major issue on the old factory castings, but just how good are the new approved aftermarket heads on core shift?

I have to think a scanned, max-effort head that someone spent a ton of time on, one port at a time, and checked along the way with a UT device and got to min wall at a few places wouldn't then break into water and create more than a few boat anchors when that program was run on a new head ??

Kp

Yes, the current equipment available in the market is very accurate.
We load CAD files of NAS standards fasteners and hardware into our Keyence IM-8000 equipment and upon the inspection of the fasteners, it provides us the actual dimensions of each fastener and will highlight and identify those that are non-compliant.

The handheld scanner will measure any part and in the case of a cylinder head, I do not see an issue scanning a port/runner and creating an actual dimensional model.

[GTX JOHN]

I believe the head casting on the old Mopar 60s/70/s
heads were used 10 times before being discarded.

We have in our experience over the last 60 years,
seen a huge discrepancy between our same casting
number small block heads in the port size.

[SBillinson]

Originally Posted by SSDiv6

Hi Steve,

Doing well, recovering from the RSV and all the ongoing wars have been keeping me extremely busy.

For measuring parts, we purchased two Keyence IM-8000 Image Dimension Measuring System. It paid by itself by reducing the time performing physical inspections and also sampling. We paid around $78K for each machine, includes full support and personnel training by Keyence.
https://www.keyence.com/landing/meas...iAAEgLAifD_BwE

We also purchased the Keyence WM-P6200 Handheld Scanner.

https://www.keyence.com/products/3d-...dels/wm-p6200/

Other great companies with 3D handhelds are Hexagon and FARO.

Many thanks, Joe. Glad to hear you're on the mend.

[SBillinson]

Originally Posted by Kevin Panzino

Not going to get involved with the side discussions regarding NHRA checking stocker heads with a device, nor the NHRA /IHRA discussion.

But I can tell you from being in industry, the level of detail that the modern laser scanners and/or a 5 axis CNC mounted digitizing probe, and the software that goes with it is at a level that blows your mind. As long as the laser/probe can get to everything, it will create a model of the shape that is within at most .001" and in most cases better than that.

What I always wondered about, is just how repeatable the castings are/core shift etc,

Certainly a major issue on the old factory castings, but just how good are the new approved aftermarket heads on core shift?

I have to think a scanned, max-effort head that someone spent a ton of time on, one port at a time, and checked along the way with a UT device and got to min wall at a few places wouldn't then break into water and create more than a few boat anchors when that program was run on a new head ??

Kp

Core shift on new casting should be much better today than even 20 years ago, but I expect it depends on the foundry and it's location. I typically sonic check before I start grinding. Then again, I've gotten pretty good at heliarcing in confined spaces....

I think material purity and porosity are probably of greater concern. When the Ford D3 Cup heads first came out (early 2000's), they had a tendency to fail at the rocker are pedestal mounts. Those were one-piece pedestals for all 8 valves subjected to relatively low open spring pressure. The top of the head would come undone. They fixed the problem--which I understood as a porosity issue--in later castings.

I've struggle mightily with porosity issues, both aluminum and cast iron (especially the old stuff). It's a nightmare.