Valve Job Question

I just dropped my heads off at the machine shop for my hemi and asked some questions on my valve job because a retired machinest who stopped by my shop took a peak at them and said that the contact area for intake valve to seat isn't wide enough. He said that on his performance engines he set them at close to .100 on the 45. My machinest says he puts the intakes at .060. So what do you guys do?

I'm far from a professional. .060 sounds a lot better to me though.

As I understand it, the wider margin flows less but last longer like in a street build and the narrower margin flows best but doesn`t last as long. And of course multi angles are favored for flow which =more power.............

The guy doing my heads does a 3 angle on everything. Grandmas 4cyl or grain truck. Just checkin on width. I agreed with the way he explained it for how wide he makes them. Thanks for the input.

I`d say he`s leaving power on the table cos a few I know do as many as 5 angles and even heard of more but I`m no machinest so,..........

It depends on the heads, wedge or Hemi, on which works best I agree with Dominc on the longevity of the V.J., I had to learn that the hard way To narrow doesn't last very long at all on the street, .060 on a wedge head might last 1200 miles, maybe less .080 will last on the street, .100 on the exhaust seats and valves will transfer more heat to the seats than .080 will

When Jason installed my 2.19 intakes he gave me a multi-angle racing v-job which he said should go 20,000 miles no problem..........

This question is in regards to the hemi heads off of old smoky. Street car. Prob never see the track.

Whatever seals and last the longest I guess...........

Just my opinion, but when it comes to my own cars durability and reliability trump ultimate power every time. Actually even when we're talking about race cars most of people on this board when they talk about race cars are referring to drag racing bracket cars. In bracket racing winning usually depends more on consistency, predictability, and reliability than it does on being the fastest car on the track. High performance always involves a trade off between maximum possible power and durability. Even in a "heads up" environment eg. Pro Stock, Nascar, Indy Car etc. you have to be able to go rounds or make it to the final lap to win. Bottom line go with a wider seat for street use and longevity.

So if I'm understanding it correctly, go 080 on intake and 100 on exhaust. I'm looking for making it live on the street. To much money in this thing to go for every hp.

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So if I'm understanding it correctly, go 080 on intake and 100 on exhaust. I'm looking for making it live on the street. To much money in this thing to go for every hp.

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This whole scenario based only on the width of the seat contact area is misleading at best IMO. The width is important, but seat concentricity, valve concentricity and the location where that 45 degree angle intersects the valve is way more important than just the width. There's no reason a .060 wide seat won't live a long life on a high performance street engine as long as the location and concentricity are what they should be.
Old worn out valve grinders, worn out seat/guide machines or stones and holders and even hurried machinists would be your worst enemy. good equipment and attention to detail will net great results and great longevity. I've used .040 wide seats on street/strip engines and we don't have any problems with longevity. Your basic 250 HP grocery getter would get a wide 45 angle and last 100,000 miles, a .060 seat done right will live as long as the rest of a good performance build if done right.
If in doubt, use some ultra fine lapping compound and only two or three twists of the stick and then look to see the where the gray line is located on the valve and if it goes all the way around the seat at the same width. If it does, you're fine, if it doesn't, have them fix it so it does.