I just got a Vette L98 (Thanks bowtie8) and it has spring cups on the seats. The valve seals rest against the the top of the guides at the top opening and against the cups at the bottom opening. After I get the valve guides milled, the seals will not rest against the top of the guides because the cups will prevent the seal from sitting lower. So my question is, can/should I have the cups milled also so the seals can sit lower or do I have to get new cups?

Green=seal
Red=cup
yellow=guide
dark grey=head
black=spring
light grey=valve

 

UT,

Nice diagram. It definitely beats the "thousand words"...

The spring cups are probably hardened to some extent, so grinding may be better than milling. Since the collar height dimension shouldn't be critical, you can probably do this on a bench grinder as long as you don't overheat the cups. A good mill file might also trim them down adequately. As long as you provide enough clearance for the seal collars and have enough spring cup collar material left to locate the bottom coils of the spring correctly, the height dimension shouldn't be a big issue.

 

Will the shop know how much to take off the guides if I tell them the lift of the cam or do I need to get some dimensions and tell them?