camshaft installed angle will also change PTV clearance on the intake and exhaust valve depending on initial grind advance and installed advanced or retarded valve timing.
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camshaft installed angle will also change PTV clearance on the intake and exhaust valve depending on initial grind advance and installed advanced or retarded valve timing.
Just saying I just checked a stock bottom end 5.9 with a 20-746-9 comp cam (216/224@50, .506 lift, 114 ls) and there’s no way in hell it will work. Intake valve hits the piston before it’s even 1/2 the way up the lobes and the exhaust is good obviously bc it’s a smaller valve. . I’m looking at 20-602-9 (205/210@50, .480/.512 lift, 112 ls) to just have something in that motor and use the other one mentioned in a 408 setup where it’ll have the reliefs.
I’m running .565 lift but it’s on 114. I checked ptv clearance before hand and everything looked good
Yea I’m not sure what’s going on, checked straight up and the intake hits. What are you guys running for rockers? I’m using 1.6 stud mounted cranes (ford) with 6.812 pushrods and the Hughes spring/retainer/locks.I just checked over the weekend with checker springs and the intake touched.
Yea adjustable
I bet the rocker is riding to far forward of the valve tip due to pushrod length.
Na they are pretty centered, I know that much. But that still wouldn’t exaplian why it opens the Intake to the point of hitting the piston. Are you installing straight up? I’m just a little dumb founded at the moment on how it works for you guys and not me. What rockers, pushrod length and lifters are you using with stock magnums heads?
When checking the clearance? Yea I used clay and I’ve done it without with looking into the intake port and spark plug hole with a camera. Just don’t have the clearance. It’s not my first go around with checking stuff, just trying to figure out what the issue is.
Maybe the cam is ground wrong, tried degreeing it?
I double checked the back of the cam before work and the part number is right but I have not tried to degree it in yet. I have another block I’m planning to use. When I get around to it I’ll will verify it wasn’t ground wrong. That crossed my mind today actually.
Also, have either the heads or the block been decked?
I just lapped the deck of the block to clean it up before jet wash. Heads had just enough taken off to clean up. Maybe .010” no more than .015”..
I believe this is the same custom grind Ryan is referring to: http://stores.hi-potek.com/hipotek-h...18-360-magnum/Quote:
Do you have an off the shelf grind you run? or is that a custom grind?