We offer full cylinder head porting, valve de-shrouding, valve bowl blending, port milling, and shortened valve guides.

Increase the flow capabilities of your cylinder head on your Z Car. From years of research and trial and error, we have applied what we've learned into a service. This setup has been tested on our Turbo 280zx pushing 350whp. We ported and polished the intake and exhaust runners, blended the valve seat bowls and removed all casting flash. We then de-shrouded the intake and exhaust valves to increase flow at certain lift points during the camshaft rotation. We removed material in the exhaust port around the valve guide area to increase port size and overall airflow. We also installed shortened valve guides to maximize airflow around the valve stem. We finished this off with a 5 angle valve job on the intake side, and a 3 angle valve job on the exhaust side.

This service is provided on an exchange basis only, price reflected does not include shipping costs.

We strongly recommend re-tuning your fuel management system after having this modification done.

This service will include the following unless otherwise specified

• Full port and polish of intake ports

• Full port and polish of exhaust ports (based on head type)

• Full De-shroud of the valves

• Open up the exhaust bowl area for more flow

• 15mm Shorter Bronze Intake valve guides

• 10mm Shorter Bronze Exhaust valve guides

• New Valve stem oil seals

• 5 angle valve job for intake valves

• 3 angle valve job for exhaust valves

• ** Bronze valve guides are now standard with all porting services **

This modification is not for emissions controlled vehicles and is designed for off road use/race use only

Extra services we offer for an additional cost :  Cylinder head milling, Drilling and tapping your head for our "Cylinder Head Cooling System Mod Kit"

Found here : https://www.godzillaraceworks.com/shop/l6-cylinder-head-cooling-system-mod-kit

After placing order, we will contact you to get specific details and make shipping arrangements. Please give 6-8 weeks turn around time to complete