Evolution of Exhaust Lobe Design and Cylinder Head Ports

banking provided by evolve member FDIC through the early part we're actually very very similar in how we open the valve then as the valve gets open we start getting faster at it and put go more energy into it this was probably designed for a 45 degree seat and so if you look at lifted diameter and everything like that going much more than 650 lift would have done bad things on the exhaust today even though the exhaust valve isn't any bigger most cylinder heads will be made with a 50 to 55 degree seat they also have some more tulip on the back side of the valve so the new exhaust valve is in Port seat the whole combination of cylinder head is better optimized for higher lift so what we'll wind up doing is running virtually the same lift on the exhaust you can see here we're about 780 lifts 790 left you see here about 8 30. after last that'll be like in the 775 range and this will be right at 800. so basically you can take the same spring install it about thirty thousands Tighter and run the same spring and take an exhaust if you run if you run 700 left on the exhaust but 800 lift on the intake you really need a different spring from intake to exhaust but you get by with 25 000 it's just install line you can see same opening grates again faster a lot more area under the Curve and you can say we have the faster closing here but at the end we put taper off a little bit now where you do see a big difference in the TDC lift as you can see here 10 before TDC the old design only had 271 thousandths left where that cursor was and the new design is 329 thousandths so that is one place where we went and took advantage of the new design he's making