Can anybody please tell me what the N head is and how it is different than any SBF head, also about the pistons for the N head, can they be used with any other SBF head if the valve grooves are machined into the pistons. thanks Bob
N heads are 351 sportsman heads. They have extremely laid over valve angles, require offset pushrod cups, etc etc. They are only made in cast iron. They flow great, about the same as a Canfield 192 if I recall.
The pistons for an 'N' head are just Ford pistons that have a different valve relief configuration. Just like twisted wedge pistons have a different than standard relief configuration. If you're wanting to grind your own valve reliefs, why not just buy the right pistons in the first place? If you grind your inline reliefs into a piston designed for an N head, you're reducing your compression a good bit.