Originally Posted by atikovi
How many miles and why do you think they need to be rebuilt? Why not just replace the oil seals and maybe lap the seats yourself?
They are probably interference fit machined to enable the valves to fit correctly when operating. I think for example Toyota has .5 degrees difference on the seat and valve. Lapping is what I worry about rebuilders may do, and if not, how well they can achieve the precision of .5 degrees with their equipment and skills.
I would get a good straight edge and check flatness myself or have a shop do that and check for cracks. If no cracks and still flat reinstall the heads.
How many miles and why do you think they need to be rebuilt? Why not just replace the oil seals and maybe lap the seats yourself?
They are probably interference fit machined to enable the valves to fit correctly when operating. I think for example Toyota has .5 degrees difference on the seat and valve. Lapping is what I worry about rebuilders may do, and if not, how well they can achieve the precision of .5 degrees with their equipment and skills.
I would get a good straight edge and check flatness myself or have a shop do that and check for cracks. If no cracks and still flat reinstall the heads.