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OK so that would put a set at the tune of $??? shipped to my door (1425 or 1034 zips from Buenos Aires)....
We could make it a nice round $400 ($360 + $50 = $410, $10 discount)
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The advantage of the ex valves wasn't for looks, just for keeping consistent combustion chamber shaping. Many stock valves have hollow heads (to lighten them up -weightwise) and that adds (or substracts actually) for compression and consistency on CR.
Follow me for just a moment. Larry Widmer is the leading pioneer in automotive engineering (my #1 hero). His web site is
www.TheOldOne.com. He talks about his "Soft Head" where combustion chamber and piston design should force the compressed charge away from the intake valve towards the exhaust valve for better combustion efficiency. With this principle he is running Hondas at 23:1 compression naturally aspirated and 13:1 at 30# of boost!
The head of the Powre Valvz is thicker making it protrude into the chamber further than stock. Ideally you would want an exhaust valve that recedes into the bowl a bit to take advantage of the Soft Head principle.
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As for the cam advice, would you elaborate a little bit more? I should do __________ (fill in the blanks) A) stop messing around with the dyno B) try to get any cam that would have good VE on my mill (I have some profiles that has over 90% VE from 3500 to 6000 rpm)
Cam selection becomes less critical with the Powre Valvz, which is the initial reason for bringing them up. Whereas traditionally an additional 4* duration on the exhaust or 0.010" more lift can make a noticeable difference, the intake Valvz will be opening when the cylinder is ready for an intake charge and closing early when appropriate to eliminate the end-of-intake cycle reversion. As the engine gets closer to peak VE (and therefore peak torque), the Powre Valvz have less influence on the engine. One of your 90% VE cams will perform about the same with or without the Powre Valvz in that narrow window of peak torque. Below that peak, the Powre Valvz will change the characteristics of the cam to reflect what the engine wants to see for that load/rpm range.
Most of the R&D and dyno time has been spent on fairly stock vehicles, or simply testing an already potent package with and without the Valvz. The Powre Valvz generate a torque curve that starts climbing immediately and sky rockets a little above idle, staying fairly flat throughout the engine's operating range. In other words, go with what you think would be the optimum cam for the peak torque you seek and let the Powre Valvz take care of the below-peak-torque range of operation. If anything, a step in the more radical direction is now reasonable since idle characteristics and low end operation will smooth out.
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This valve would work with extensively bowl ported and radii blended heads? kind of that one you built for I don't remember how with had channeled intakes? I did the channel thing once and my bbuddies laughed at me... it was kinda nice having a 10 years payback with them
If a trick works well with regular valves, it will most likely work well with the Powre Valvz. If it sucks with normal valves, then it will probably suck with the Powre Valvz. What the Valvz are going to do for you is delay the opening of the intake valve until the cylinder is ready for the charge, and close the valve early to prevent pushing what charge you already have in the cylinder from getting pushed back into the intake manifold. It's just that simple. If you have better ports, then these ports are going to benefit the engine WHEN THE INTAKE VALVE IS EFFECTIVELY OPEN the same as it would with typical intake valves. If you have a lousy exhaust system, the Valvz will Band-Aid that some by preventing back pressure from diluting the intake charge with spent gasses. The better the engine design (port work manifolding, etc) the better it will run. So yes, it will work well with the head I did for Greg Mander.
Mike