Cylinder Head 7

Finished up on the porting clean-up. These are a couple of shots of the number 1 cylinder with different light then number 3. The others are similar. I didn't realize it earlier, but someone has been in here before as the valve guides (as you can see on close up) are nicked on the ends. Seems to be a perfect fit to a burr from a die grinder. Note that the lumps and bumps have been for the most part removed. I also measured the camshafts and found that they have been reground once before. These older cams should have a 5/16" lift, but they have an 11/32" lift. Definately not factory correct. Later c-type heads featured 3/8" lift. I'm not sure what to think of the ones I have at this point. Some of the older cams are exchanged for later xj type with 3/8"lift and less abrupt valve action that primarily makes the valve train quieter.

Finally the front engine seal conversion arrived and I installed it as well as the front chain cover and the water pump. By the way, the nail has been replaced with a proper pin and the wire holding the pulley housing together has been replaced with a proper snap ring.

Cylinder Head 6

Started to clean up the intake ports. They will be expanded from the current size of about 1-1/4" to 1-3/8" and will be essentially straightened a little through the process. The boss for the intake valve will also be reduced in size. This is not considered radical for this engine. It should remain very tractable but should breathe easier and provide more mid-range torque and throttle response. Also gonna drink more. The numbers for this head are W-1628-8. That means that it is the 628th made and is set up for a 8:1 compression ratio. This head also has a very low lift set of camshafts as did all of the early models. In fact, it can't be changed to a higher lift like the xk120MC version without machining the lifter buckets to clear the cam lobes.


The last two shots are from the exhaust port toward the valve seat. I need a longer set of dies to finish up the rough-in.

Cylinder Head 5

More of the roughed in exhaust ports. Note that I made the valve guide boss smaller and sleeker. I'm planning on reconditioning the guides so I'm working around them. If I were going to replace them, the entire boss could be removed and allow only the stem to stand alone upon replacement.

Cylinder Head 4

So this is the first roughed out exhaust port. The idea here is to clean up the lumps and bumps that can restrict air flow without dramatically increasing the size. Much cleaner.

Cylinder Head 3

Cylinder Head 2

First shot is the start of clean up of the exhaust port. Notice how rough the casting with ridges et al.

The remaining shots are of the intake port. Notice the curve and the rough casting again. The intake port is round while the exhaust port is rectangular and if you note on the first photo again, the edge is irregular. Typically, these ports are cleaned up when mated to the respective manifolds. The intakes are very close, the exhausts are all over the place

Cylinder Head

These are a couple of typical images of the exhaust ports on the cylinder head. This is a type B head so it has 1.65"(1-5/8") which are the same as almost all XK's. So this is the same as in the desireable C type head. This head is not known for its power but rather for torque and fuel economy. The intake ports are offset from the combustion chambers which causes a swirl to the fuel/air mixture. They are also relatively small so the mixture velocity is relatively high and that helps torque. So I want to breathe on these a bit with the idea that torque is most important, horsepower is ok, mileage be damned. So what I will be doing is cleaning up the ports and taking out the casting obstructions and enlarging slightly.