Digitizing Cylinder Heads Help
 

Guys I need some help on understanding digitizing cylinder heads. I know this should be in the tech section, but I would like to get as many opinions as possible to understanding how this process works. Can the complete head be digitized. Meaning ports, bowl area, combustion chambers, every little nook and cranny so to speak.

Re: Digitizing Cylinder Heads Help
 

You can digitize anywhere the probe (usually 3mm dia.) can get to.

Take a look at this.

https://www.youtube.com/watch?v=XN8xRUzFF2k

Re: Digitizing Cylinder Heads Help
 

Ken,
Yes, the ports and chambers can be fully digitized.

Re: Digitizing Cylinder Heads Help
 

The are probe digitizers, laser digitizers and 3D scanners.
Yes, you can digitize and reverse engineer a cylinder head and even more complex parts.

Re: Digitizing Cylinder Heads Help
 

Interesting video, but that looks like a lengthy process, and it does not show how far then can go. So there are 3 types of scanners, they have to be very expensive. Can a laser scanner digitize around bends like a short turn radius. It looks like the technology is here, but how good is it really. I guess I'm not sold on it yet. Time do more research, thanks guys.

Re: Digitizing Cylinder Heads Help
 

The technology has been there for quite some time to digitize cylinder heads. If NHRA could get together with the manufactures they could really find out who's heads have been massaged. Not that there are any ported heads in stock.

Re: Digitizing Cylinder Heads Help
 

Now that is really funny to read first thing in the morning !

Re: Digitizing Cylinder Heads Help
 

Yes, 3D laser scanner or a Renishaw Cyclone digitizer can digitize around bends, contours, radiuses and more.

Re: Digitizing Cylinder Heads Help
 

Ken I understand being skeptical of the technology, but it really is that accurate these days. Most high end CNC machines these days have CMM probes on 3,4 or 5 axes arms inside the machine that do spot quality check's to .0005" accuracy, and then per an algorithm adjust tool paths for cutter wear, ambient temp and humidity differences, etc. Being a reporter, maybe you could drum up interest from a laser scanner/ CMM company to do an in depth 'how it works' article. What head are you specifically looking to scan? I ask because a lot of late model parts are available from the OEM via Sema: https://www.semagarage.com/techtransfer/Index


Some of the late model head CNC porting shops might have the base OEM CAD and/or full combustion, intake, exhaust port scanning capabilities too. It is isn't cheap, but the most accurate way, by far, to analyze the CFD flow in and out of the engine. Interesting stuff, gonna follow this thread...

Re: Digitizing Cylinder Heads Help
 

Our people say they can get to 99% accuracy from a port, however, when going to the seat area, there are metrics like "picking the throat size." In this case we chose to go 92% that reduced flow quite significantly, so be very careful. We are doing a 642 cubic inch Pontiac engine and the throat size is the limiting factor. We brought the flow back with a carefully constructed intake manifold runner by Mr RPM himself, "the Kat" Rick Katterjohn.


Lynn McCarty
www.ramairv.com
317.260.3486

Re: Digitizing Cylinder Heads Help
 

when we were working on the D3 heads for the 429 combination I had a NASCAR head "scanned" by the Ford lab. They gave us a solid model file that even included the coolant passages inside the head. I'm not sure how they did it. Converting it to something usable in a CNC took some doing though.

I know for larger items the scan is different and they applied a white powder. We did this with Morgan's prostock car at one point.

If you're looking for something late model it's possible the OEM has data or might be willing to help you with a scan.

Re: Digitizing Cylinder Heads Help
 

Jesse,

Most of the OEM's and big aerospace companies either use the Renishaw Cyclone digitizer or the Nikon Laser scanner. You can basically reverse engineer anything with those scanners.

Re: Digitizing Cylinder Heads Help
 

Well I guess NHRA is a big company now, they purchased a $60,000 scanner to use on showdown cars and stock eliminator cars. I received a phone call from Ford Performance letting me know that NHRA scanned cylinder heads for the Ford showdown cars. For six weeks all Ford show down cars were illegal. They just reversed that rule and said show down cars will have designated cylinder heads starting 2020. So with show down cars out of the way my guess would be they are going to focus on Stock Eliminator cars at Indy. It is no longer just runner volume, cylinder heads have to match all OEM and Aftermarket (ie Edelbrock) After 50+ years there is a new sheriff in town.


Jim D'Amore

Re: Digitizing Cylinder Heads Help
 

I know. Very Very old thread. Does anyone know what happened to this?


Stan


PS - Took awhile for the memory to work lol There was another thread somewhat like this a few years later which I had made a post in. But that had no real answer either.

Re: Digitizing Cylinder Heads Help
 

This brings back memories of too much too soon. In 1996 through conversations I had with Jere Stahl, the pro stock team I was working with decided to go this route.

The only person we could find that was even slightly interested was a wheel maker (of all people) who had just bought a 5 axis and was willing to try but not sure if it could be done. "I need to make chips 24/7" was what was his motivation.

The plan was to digitize the best port(s) on the best handground heads we had and use that as the program for all ports on a new head. The plan failed because the inhouse engine builder was very protective of his position and status and threw wrenches into the plan anytime he could.

And looking back along with knowing what we now know, that plan was probably flawed. I have the impression that even with the most precise standarization that could be done, different cylinders are going to want different things.

So many things have changed for the better. I can't tell you how many times both the head builder and the manifold constructor would say variations of "I wasn't in the mood" or "I just haven't been feeling it" when contacted about long delays in delivery of what they'd already been paid for.

Re: Digitizing Cylinder Heads Help
 

The current digitizing equipment available nowadays would blow your mind!

I purchased for use by my Inspectors, a laser-based CMM made by Keyence, that will measure parts in seconds based on a reference CAD file; no calipers or other measuring devices are required.

We also have a Keyence hand-held, laser-based scanner that will measure parts and create a CAD file.

Re: Digitizing Cylinder Heads Help
 

When NHRA decided to do that, they, a tech inspector, and a couple of engine builders got sued.


Some people vehemently defend their cheating, and NHRA doesn't want the hassle of all of it.

Re: Digitizing Cylinder Heads Help
 

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

Re: Digitizing Cylinder Heads Help
 

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.

Re: Digitizing Cylinder Heads Help
 

Bret

Does anyone have a WAG of how many / what % of the cars have illegal heads. If this number is high enough I don't see the IHRA doing this. Most people will not build another engine to run IHRA. I don't see the IHRA making a rule which would limit car counts.


Stan

Re: Digitizing Cylinder Heads Help
 

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.

Re: Digitizing Cylinder Heads Help
 

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.

Re: Digitizing Cylinder Heads Help
 

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.

Re: Digitizing Cylinder Heads Help
 

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

Re: Digitizing Cylinder Heads Help
 

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

Re: Digitizing Cylinder Heads Help
 

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.

Re: Digitizing Cylinder Heads Help
 

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.

Re: Digitizing Cylinder Heads Help
 

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.

Re: Digitizing Cylinder Heads Help
 

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

Re: Digitizing Cylinder Heads Help
 

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.