Leaky Valves? Speedway Motors 461 DH Aluminum Heads. 

These Speedway DH heads are Flotec 180cc castings. It's an offshore copy of a Dart head. Nice clean casting and an ok head for a mild 327-355 sbc street build. Any brand head (USA or not) out of the box needs to be checked over before being used.

Looks great Matt. Certainly a good way to check it. And anyone can do this at home. The valve job is probably pretty good without physically looking at it. You probably have you a good set of heads. I like the chambers in the heads.👍 Have a great day Matt.

Never worried about a brand new head leaking around the valve seat a tad bit if it is a "name brand" head as the seats are normally machined perfectly in most cases and the valves are generally a decent quality. As a general rule of thumb, if the valves do leak a minor amount, they will seat within a minute or so when the engine is run. If a builder wants to make sure that his/her heads are "perfect", would be to pull them apart and lap the valves. Then... you know that they will seal 100% or more work is needed. My two cents worth...

Hey I got my heads back from the port shop. ended up going 2.055 intake valves (because I had em sitting here) but it picked up from 225 cfm at .5 lift 243cfm @.500 lift. With basically just smoothing the ports and de-shrouding the valves. So fyi these likely flow 15-20cfm below advertised depending on the head. 243cfm should be enough to hit the 500hp mark. And the gains were all positive through the lift of the valve. The heads max at that lift out at no reason to go over 0.550 lift

AROUND THE 4 MINUTE MARK you may notice a little thinner running down the surface of the head. That's not from the valve seat. I overfilled that port and a little bit ran out when I moved the head.

I got pics of my speedway camel humps at the port but waiting on flow tests for my 0.100 longer valves so i can run .6 lift. I'd like to share with you but no way to pm here. you really should get the valves de-shrouded yours look as bad as mine were. people say as shipped these are only flowing in the 225cfm range but don't say at what lift. but the high ridge around the valve in the chamber is gonna kill performance and its easy to remove. especially if your running the lower lift valves. having a machine shop do the de-shroud wont be expensive its done on a machine not by hand and wont affect valve seat seal.