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FullAuto Cyclinder Head

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I am trying to learn what is the differences between the Combat head, valve angle, etc verses this newer FullAuto head.  Can't seem to get any particular specs. Anyone out there who has experience and ideally specifications on this topic? 

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The FullAuto head  is a higher quality casting. better alloy, improved port shape, valve seats and threads . Made to provide a replacement for a factory head that has a reputation for poor quality. I dont think the valve angles were changed. Not the final word  for performance developement ,and not intended to be .

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Ken started NHT head developement using my website head article, contacting me during it's inception.

Development further included to others like Jim Comstock who added flow changes for different characteristics, probably up the rpm range to racer specs or at least to correct the combat big port disaster.

Jim and I agree that in fact a combat engine with an RH1 is better than a combat head. A combat head is IMO ruined....This is based on my dyno tests 20 years ago...

I own a 750 FA head #99. full interchange with stock NHT head dimensions. Yet to be used...

FA went out of production years ago. The STS is a totally new and bought out Ken at FA . However, STS in Florida, USA is a totally new head & sold by "sales at CNW" as he no longer builds bikes.

For 850 engines it is likely the STS head (including full auto) port shape and is better than a RH4 as many are cracked at the intake guide due to stone age porting making extremely thin port wall next to the guide/valve spring pocket. This makes RH10 small port heads at a $$$$ GBP premium...

My biggest disappointment overall that both Ken at fullaut, AND STS is, they ignored my suggestion to make small bolt pattern 500-600-650 heads which would have been easy-peasy using the same down draft casting.

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Small bolt pattern heads would have been a welcome  addition  in the UK but they probably thought the demand would not warrant the trouble. Over here they would have been seen as a direct replacement with no necessary extra  performance modifications.  I think the US has  a market that would buy a  basic big bolt  casting ( cheaper !)   and then  heavily modify it to a semi race spec.

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When talking to Steve Maney at his works in early 2018 i commented on the cylinder heads he had lined up for work doing/work done and asked him about the Full auto head and what he thought about it. He said that to get enough metal on the casting to allow for the desired port shapes Steve asked if Ken (full auto chappie) would alter the pattern. Ken took umbridge at that suggestion. (I think Ken was after selling Steve the patterns but i could be mistaken there)

Later, whilst talking to Ashley at AN about cylinder heads he told me that AN were offered the patterns for the full auto head when Ken was selling up. He said the patterns were not good (my words, his were a bit stronger) as they were made of wood and that the castings that AN saw were of the wrong alloy. When STS got hold of the FA patterns they realised they were in poor shape had them remade in better materials and got them cast in the right alloy.   

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Supplying the aftermarket needs for NHT heads discussion 20 years ago, when I was involved, seemed to be two fold. The lack of good RH4 since a large percentage were cracked making RH10 the easiest fix. This was exacerbated by the old ageing guys bringing out the fleet of undesired RH4/MK3's. Add to that horrible combat heads caused the two main demand issues.

With the single down draft core making a small bolt pattern is incredibly easy. Leave out the desaxe counterbore and reposition the 4 head bolt holes to suit. Valve seats are not change for the whole NHT series. Lacking a large quantity of domi engines here in the US there are still very few unbutchered domi (small bolt pattern) heads.

The final small detail is making the head top oiler instead of side oiler...again machining childs play.

Certainly some need to discuss the remanufacturing process and it's final demise. It may all be true.

I also consider looking at defineing the original need... which was the beginning of this journey when I was involved..

 


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