Cylinder Head Rebuild Service

Base pricing includes disassembly, cleaning, blasting, measuring, and report of findings for all styles of heads.

Pricing Does not include cost of guides or valve stem seals, we will contact you with part pricing and brand options before performing any further work!!!

Ship or bring your head into the shop for a rebuild!

We often get asked what it takes to bring a head back up to par and what actually gets done to it during the process.

Each head starts out with a complete disassembly. We remove the valve train, stem seals, water pipes, and core plugs. The head then gets its first initial cleaning into our 160 degree immersion tank to loosen the buildup of carbon, dirt, and any loose materials.

While that is running its cycle in the tank, all the valve train and components that were removed are put into the ultrasonic cleaner for their first cycle as well.

Once the head is removed from the hot tank, it gets placed into our pressure testing unit. This had adapter plates that simulate it being bolted onto an engine block and seals the cooling system. We can then pressure test the head to about three times the vehicles operating pressure while inspecting the entire casting for cracks that could have been caused from overheating, bent valves, piston contact, and many other unfortunate scenarios.

Once the head has passed pressure testing, all the valve guides, valves, and springs are measured and tested. At this time we will have a full understanding of anything that is out of specification and needs to be replaced. At this point, we will reach out with our findings, and replacement part options/pricing. 

It is very common to have valve guides out of tolerance in relation to the valve stem diameter. When this occurs, excessive oil makes it into the combustion chamber or gets burnt in the exhaust ports causing carbon buildup. If a guide is worn, it will also not be perfectly round anymore and will be a slight oval. This leads to valve rock and inadequate positioning of the valve face to the valve seat causing high leak down, and premature wear. If the guides are worn like this, the geometry is not correct, and we will not perform a valve job until the guides are replaced.

If any valve guides are replaced, valve seat cutting is required for proper sealing of the new valve stem positioning.

The second cleaning phase comes in form of soda blasting. This removes carbon buildup you will often see inside the ports and in the combustion chamber. Soda blasting is our go-to for several reasons, but the biggest one is that it is completely safe for the engine and cooling system. In the extremely rare scenario the ultrasonic or hot tank didn’t remove it all, there is no chance of engine damage line you can have happen with glass bead blasting or other hard abrasives.

Next, after removing and installing guides to the correct height, we then size them to the specifications required with diamond honing. This system is ideal for getting the valve-to-guide clearance exactly where we want down to the .0001” of an inch.

At this time the valves are refaced or reuse if they passed the initial measurement inspection. 

The head is then setup on our CNC for its valve job. With perfect valve guides, we only use carbide pilots, and carbide cutters. Pairing that with our Haas CNC we have created the most ridged setup to achieve the most concentric valve seats possible. Most heads have a three angle valve job from the factory and will often match those angles, however if it is a performance head we will introduce some of our secret sauce for fine tuning the angles and margins that we see fit.

After everything is cut, we vacuum test each port with its corresponding valve to ensure perfect sealing.

While still on the CNC, we then resurface the head with either a CBN or PCD single point fly cutter depending on the head material. We will reach out and ask what head gasket you will be using so we can get the correct surface finish for that manufactures gasket. Measuring the surface finish with a profilometer is often overlooked and can impede on proper head gasket sealing if not correct.

Finally onto the final cleaning! This is the very stringent process of using combinations of ultrasonic, spray cabinets, and the immersion tank to get the head ready for assembly. Everything in the head is cleaned once again, and inspected a final time. All the valves are test fitted for proper stem height specifications and the modified is needed, and will get installed with new seals. If requested for a solid lifter/bucket head, you can send us your cams for doing an initial valve lash setup.

Contact us if you have a project that does not fall into basic categories from the drop downs or would like to discuss a custom build!