Dissecting a cylinder head

[Luckypabst]

Here are a few photos of a 1.6 NA hydro head in cross-section. Unfortunately my degreaser turned all the fresh cut surfaces a nice shade of gray. I also quickly surfaced one slice to bring out the detail in the typical crack between valve seats.



Between valves, cyl #4:


Same:


Between cyl #3 & cyl #4:


Exhaust port, cyl #3:


Intake port, cyl #3:


Crack detail, cyl #4. Crack extends to about the sharpie mark:


Chris

[JASGTi]

Now I can see clearly why we don't worry to much about cracks between valves.

[burn_your_money]

How wide was that crack? It's getting pretty close to the water jacket.

Are all the ports and water jacket relationships the same? You're showing some excellent info for porting heads.

[Luckypabst]

I figured the porters would find that interesting.

The cracks were on the wide end of acceptable when viewed from the combustion chamber. I haven't looked but I would expect those cracks to extend into the ports, though I never experienced any related issues.

[CrazyAndy]

I have seen cross-sections of these heads before, but non with detailed shots of both the intake and exhaust ports; thank you.  That will be a lot of help to those who were wondering about the water jacket of the inner radius of both ports, as well as the maximum save porting depth.

[wdkingery]

Dude thanks for these sweet photos! That baby doll head was fairly ***ed up, but the cross sections were neat!

[theman53]

Dude thanks for these sweet photos! That baby doll head was fairly ***ed up, but the cross sections were neat!

I usually don't notice those things but that was the first thing I noticed in those pics. I thought it cool it was winking at me.

Also, you can see why the exhaust side there really aren't that many big gains to be had, but the intake has the huge hump to take down and get flow. That is why I gained 40% on the intake and only 15% on the exhaust on my last head. I will soon be getting my new head *fingers crossed* and will show some stupid numbers on that.

[Luckypabst]

For the record, this head is cracked into the water jacket up in the prechamber and injector wells. I'm not sacrificing virgins over here 

Chris

[ricosuave]

very cool, thanks for posting

[Gizmoman]

old school CT scan - very cool

[fast57chevrcr]

  I agree with every body great Job !!!!

[Syncroincity]

Dude thanks for these sweet photos! That baby doll head was fairly ***ed up, but the cross sections were neat!

First thing I thought of: