I'm in the process of a slow rebuild on a 428 as money persists. I have some C6AE-R heads that I recently had valve guides and hardened exhaust seats installed.

When the seats are installed they are square with no angle cut into them to match the valve. Being a penny pinching High School kid I decided do the whole valve job my self, and save $150. Iv done a few sets of heads before along with my grandpa who has done valve jobs for over 30 years. We have all our own equipment.

We started the angle in the seats with the hand rotated carbide tool. This is also used to narrow seats down when they get too wide after grinding. "Sorry I cant remember the correct name"

One question came to my mind. How far do I cut the new exhaust seats down from being square?? There is currently about .100 thousandths difference between the stems on the intake and exhaust valves when installed.

When you look at the combustion chamber on the heads you can clearly see that the exhaust valve is sticking out farther in the combustion chamber/toward the piston.

I'm not entirely sure what to do. The first thing that came to mind was that I should just set all of the intake and exhaust the same. I'm worried that the exhaust valves will hit the pistons if not cut in deep enough.

I'm sorry if I lost any of you guys, any help is appreciated.

Nick

 

Personally I would have left this to the machinist based on the costs. They do it for a living, and can be held responsible for it getting botched. JMO Grinding an old set of heads for a better seat after 75-150k is one thing, the tooling of a new setup ? I dunno. Wish I had the answers you seek.

 

That's just the thing I should have just swallowed my pride and left it to the machinist. I'm still not leaving that out as an option. I haven't went far enough to mess anything up yet so I think a trip back to the machinist is in order.

Thanks

Nick