Cylinder Head - New 6.5L Naturally Aspirated Optimizer Head

New genuine AM General - GEP Optimizer ™ 6.5L Cylinder head for Non-Turbo Naturally Aspirated engines.

This is the latest version of the cylinder head that is interchangeable with GM 6.5L engines as well as current production 6.5L engines. This version of the cylinder head features metallurgy improvements not found in original GM heads as well as small changes.

Head is typically in-stock but can be backordered via store when not in stock to reserve your units before they arrive. Ships to your door via UPS Ground (a bonus as this does not require truck freight).

This is great for engine full rebuilds where you want confidence in a known quality head and don't want to chance some off-shore knock-off head's quality on your work.

This is a top notch quality head with all the right machining tolerances and correct non-magnetic pre-combustion ports specifically for non-turbo 6.5L applications that will support 170 HP clean performance without a turbo. While not directly related, these would make a suitable replacement for 6.2L engines needing updated heads, will make an almost direct swap on 1990-1993 6.2L engines (no changes) and require some changes on 1982-1989 6.2L engines in the form of injection lines, injectors and brackets.

We've been faced many times with pulling heads on 6.5 engines and performing replacements and asking the question whether the existing engine was "worth" the cost of good heads or cheap knock-off heads. For our own engines, we always opt for the quality unit because it's just not worth the risk of destroying a good short-block over a poorly designed head.