My home inspection of Speedmaster heads

pittsburghracer said

As far as valve jobs some of you guys are spoiled. I got away from stones years ago and moved to Neway valve seat cutters but I’m limited to your basic 60-45-30-15-10 valve angles instead of you custom angles. I almost had that ability 6 years ago when a friend closing his speed shop offered me his mill and all attachments for 1200.00. If my son had any interest in doing heads I would have bought it but he doesn’t so I didn’t. I think my heads do ok with old school technology so I’m stuck there. For guys that have never seen Neway cutters here’s a link. I bought mine in bits and pieces on eBay over the years


Neway Valve Seat Cutting System

Click to expand...

Dang for that money I'd have snatched that mill up in a New York second.

It's crazy how important not only the angles are, but the worth of the angles.

And it depends on the bowl too. On 45 degree stuff for MoPar OE junk I like a 4 angle cut with the bottom cut a full .100 wide. I can't remember the angles at the moment, but IIRC the rest of the angles are all at least .060 wide if not .080.

On the 50 degree stuff the bottom cut isn't as wide...maybe .080ish IIRC.

It all makes a big difference not only in flow through the port, but how well the port flows backwards and even how well they flow at different test pressures.