NEW HEAD UPDATE
We have received 2 new 6.5 to 1 pre-production heads that will be used for engineering evaluation before production is authorized.
Engineering evaluation consists of verification of all machined surfaces, flatness verification, visual verification, verification of wall thickness, and performance verification.
The machined surfaces on the first head have been verified to be correct by careful measurement and comparing the measurements to Ford drawing A-6050.
The revised water passage holes to divert more coolant to the rear are in their correct locations and look good.
The bottom of the new head was verified to be flat by placing it on a surface plate and the inability to slide a 0.002-inch feeler gauge anywhere between the head and the surface plate.
Visually, the combustion chambers all look good.
Visually, the new head was placed on 2 original cylinder blocks and held in place with 7/16 inch bolts through 2 stud holes. The length and width of the new head matched the original cylinder blocks and there was no overhang.
Visually, the 3 small marks where core wires protruded were present, and with exception of 4 small discrepancies, everything looked good.
The 4 discrepancies are that the delta foundry mark should be better defined, the area below the distributor retention setscrew has excess material, there is excess material where the water outlet meets the new head, and the scallops have evidence of machining instead of being a cast surface.
Each of the 4 exterior discrepancies could be corrected with a die grinder, Dremel tool, and a needle scaler from Harbor Freight, but our goal is to provide a part that may only require a minor touchup for points judging. We will be asking the foundry to make changes to the tooling to correct the discrepancies before the production run.
The new head has increased wall thickness in several areas that are prone to cracking. The first head has been cut apart to verify wall thickness and to ensure that there is no porosity, and everything looked great.
The attached pictures show the top and bottom of the new head, and after I cut it apart for wall thickness verification.
The second head will be sent to Dennis Kliesen for performance evaluation. Dennis has over 17,000 miles on his new engine that is currently using a 6.0 to 1 head. Dennis and I are working on a plan for evaluation.
There are many people actively building the new engine and their comments can be found at
https://www.facebook.com/groups/1123377268114692