Guest Posted July 9, 2002 Share Posted July 9, 2002 Wow Monte I just read your post on the valve geometry, I guess when I get back to my motor tomorrow I am going to check that out on my valves. I have Scorpion 1.5 ratio roller rockers with a comp extreme energy 274 cam, what do you think of that combination Monte? It really has me thinking and hopping it will be fine. Should I check this at zero lash or after I have done the final adjustment? "Is your cam a solid roller or hydro? If its a hydro you can adjust them with the engine running. If its a solid you should adjust them valve by valve with a feeler gauge. You can get rocker splash guards from the local auto store which will keep the oil from going everywhere. Not all splash guards work with roller rockers. Take a rocker with you to make sure you can get it on. Mine are super super hard to get on but they do work. Also before you install all of the roller rockers. You need to check your rocker geometry. Many roller rockers depending on design can change your rocker geometry. This also is effected by how much lift your cam has. The tip of the rocker arm should ride close to the center of the valve stem during the lift. If the tip of the rocker rides on the outside or inside edge of the stem you have a geometry problem and this can lead to stress on the value and failure of the valve or the valve guide. You can buy a push rod length checker that is adjustable so you can determine the proper length push rod for your set up. The correct length push rod should allow the tip of the rocker to travel in the center of the valve stem during the opening and closing of the valve. The rocker tip will travel a little toward the outside edge of the stem and a little toward the inside during this process but most of the time should be in the center section of the valve stem . Again if the rocker tip rides from outside of the valve stem to the center or inside of the valve stem to the center you have a geometry problem. You also need to check the clearance between the stud and rocker at full lift. Some roller rockers can bind on the stud at full lift. It is sometimes hard to see as it will usually bind on the bottom side of the rocker toward the tip of the rocker. Monte" Link to comment Share on other sites More sharing options...
Monte Posted July 9, 2002 Share Posted July 9, 2002 I think you will be happy with the 274. I would assume your talking the hydro flat tappet and not the solid roller? The 274 hydro pulls real well to about 5500 and has a very crisp throttle response. Its a good grind from comp. I would check your geometry first before start up. Use your existing push rods and see where its at. As far as lash goes, if its the hydro you want to preload the lifter. Since you dont have oil pressure, tighten the nut on the rocker until the push rod starts to become hard to turn between your index finger and thumb. Use common sense. If you have to grunt to turn it thats to tight. You do this with the lifter on the "back side" of the lobe. Not during the lift or once it starts to lift. The push rods you have will probably be fine. Monte. Link to comment Share on other sites More sharing options...
Guest Posted July 9, 2002 Share Posted July 9, 2002 OK thanks Monte; I like the lift the push rod up and down until there is no movement with a slight pressure one the lifter as my cousin says the top of the hydraulic lifter will sometimes turn if you are using the turn method. I used the harmonic bolt to turn it a few degrees at a time and took out any endplay. The new valve adjusters with the Scorpions roller rockers were sweet for taking out endplay just a touch of a slight turn and it was gone. I plan to preload it at least a half turn, as I did pump up my Rhoads lifters manually as much as possible. They will have bleed down by the time I put the 1/2 turn on them. I will definitely check the geometry also. Link to comment Share on other sites More sharing options...
Guest Posted July 9, 2002 Share Posted July 9, 2002 ADG, don't run those lifters at 1/2 turn it'll kill them! 1/4 turn max 1/8 better! Don Link to comment Share on other sites More sharing options...
Guest Posted July 10, 2002 Share Posted July 10, 2002 Hey Don, are you saying even if the lifters are not pumped up yet? I was going to adjust them cold ½ and after I got her fired up, I was going to readjust them to a 1/4. I guess the question is should I adjust them 1/4 turn even cold. Link to comment Share on other sites More sharing options...
Guest Posted July 13, 2002 Share Posted July 13, 2002 Yes Link to comment Share on other sites More sharing options...
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