Remember, if you don't have a properly build strong bottom half of the engine, eventually it doesn't matter how strong the engine runs, as it won't run too long, if its truly making real HP!! It's the "unglamorous" parts, that the true racer/team owner should be concerned about first!!  You'll never win if you don't finish first!!

  It's common knowledge among "TRUE" racing professionals that even for a motorcycle engine, 20, $30,000 or even twice that for certain factory level plus, engines is not too much to pay. If you're getting what you wanted. We've just seen too many people pay way too much for engines not really worth half what they paid for them. As we get time, we'll add more, just for food for thought. We aren't in the business nor would we publicly name any of these 'engine builders' as we try to be a whole lot more professional than that. We'll some time be posting engine components that show how you don't want your engine builder to build your engine as well. 

 **A very important note here**; The finish appearance in the of a chamber or port, as shown below means absolutely  nothing when it comes to performance. You can look at  work that looks beautiful but performs worse than stock. You see pics regularly in magazines of "beautiful work" that really isn't worth the hassle of removing the parts & sending them to get done. Although top level work can look great, its the shaping, contouring, matching machine work, matching of all related parts, etc etc, that really matters. Sometimes an area in the head benefits from being as smooth as glass, sometimes we actually cut grooves in an area, or don't touch it at all. Sometimes we even weld in an area and rework it.  

 The following pics show just a fraction of what our capabilities are, but at least  will help familiarize some people on some things they maybe have wondered about for a long time.

Now we cut the entire face in till the margin the exact dimension it has to be. This measurement & the small chamfer on the outer dia of the valve face are super critical when running close valve to valve clearances 

Granted if some "engine builder" is putting together a typical "race engine", by their definition, many of the below points don't matter & unfortunately for his customer, many times don't even mean anything to the "engine builder".  Many "engine builders" rely on the parts to "just work" rather than completely understanding & checking ea. aspect of the components design & how they interact with ea. other. Many don't even check things like valve to valve clearance. This means one of several things; they are either unaware of how important that is, they don't care, they don't know how to ck it, or, they aren't really building a true upper level race engine. If they were, they would be utilizing all the "available room possible" to make stout reliable hp & tq. You almost always wind up running the intake valve and the exhaust valve very close to one another (as they pass ea. other) while one is closing & the other is opening. Using up all the opportunity there is, is one reason for having cams special ground to our own specs, to maximize inlet & exhaust flow characteristics.  

Some of the factors that determine all the valve specs are; RPM you want or need to run, the backside or tulip profile according to if it's an intake or exhaust, & what is the bowl or throat area design. The depth you want the valve into the chamber/head, (many times that is determined by how thick the top of the pistons you are using are, which then determines how deep you can fly-cut them). Then the material you are using for the valves, & if titanium we use completely different material for the valve seats for several reasons. Also cam base circle, & definitely cam profile, what springs you need to run, which is determined by the RPM you need or want to run, the cam profile, & definitely if its a symmetrical or non-symmetrical grind which is part of the cam profile, and then the weight of the valve. The retainer style & dimension also goes hand in hand with valve design. Also, do you want or need to run a undercut valve stem, for flow or weight, or heat issues. Are you coating the valve or not. The type of guide material you are using for the valve guides is also very critical in determining the valve specs & visa versa as well. The diameter of the valve head. That's a humorous subject in itself. Many people think that an oversize valve, in and of itself, allows for more flow, DEFINITELY NOT SO!! Unless the proper throat work is done, and  in most cases the reshaping of the critical areas in the combustion chamber are are not properly modified, they can flow LESS AIR!! and many times cause added unwanted turbulence, & other problems. But, when many people hear the word oversize valves, they mistakenly think that that atomically means more power. We see a lot of heads done by well known & "reputable" facilities, that quite frankly they should be embarrassed to let out of their building. But since we are definitely not here to knock anyone in particulars work, we'll leave it at that!! The location & angle you want the valve to be in the head, also determines its makeup.  You can change the angle of the valves, even if its an overhead cam engine, but that for only the very top dollar Factory plus, level engines generally. It generally entails oversize buckets, & installing over-size OD valve guides, so everything can be re-machined so the new angles will mate to the cam properly, along with many more other critical mods.