PTV - Need some help
#1
PTV - Need some help
I'm building a TSP LS 402.
Pistons are +5cc
Cam is 242/248 112, gross valve lift .610/.615
Heads are TFS 235's CNC 70cc
Yella Terra 1.7 rockers
Lunati Hydraulic lifters 72332
I measured and purchased the pushrods, no clicking at zero lash.
I set up clay on #1, torqued down the head and turned the engine over a couple times. To my surprise, there are no noticable impressions in the clay.
I repeated the test with solid lifters and longer pushrods which yielded the same result.
Given that there are valve reliefs I would still think there would be some impression made.
Does this sound like a springs issue?
Update - I read the technical specs on the heads and the springs are good for 650 max lift so I don't think it's springs. This could also be timing right? If my timing is off wouldn't this be a symptom?
Thanks,
Mowpow
Pistons are +5cc
Cam is 242/248 112, gross valve lift .610/.615
Heads are TFS 235's CNC 70cc
Yella Terra 1.7 rockers
Lunati Hydraulic lifters 72332
I measured and purchased the pushrods, no clicking at zero lash.
I set up clay on #1, torqued down the head and turned the engine over a couple times. To my surprise, there are no noticable impressions in the clay.
I repeated the test with solid lifters and longer pushrods which yielded the same result.
Given that there are valve reliefs I would still think there would be some impression made.
Does this sound like a springs issue?
Update - I read the technical specs on the heads and the springs are good for 650 max lift so I don't think it's springs. This could also be timing right? If my timing is off wouldn't this be a symptom?
Thanks,
Mowpow
Last edited by mowpow; 05-11-2012 at 11:32 PM.
#2
Where is the intake lobe centerline of the cam set? Sounds like the cam is massivley retarded if there is a bunch of valve to piston clearance. Are you sure timing chain marks are dead on?