Help. Chewed up valve tips. pictures
10-06-2011, 11:31 AM
#25
I don't think it's the high lift and double springs. I can't offer an alternative diagnosis but I have been running the MS4 (239/242 0.649"/0.609" 111+1 LSA) with bone stock 799 heads and 0.650" double springs for 20K miles and I have about 5-7K miles on my 0.675" double springs without issue. Stock rockers (with Comp trunnion upgrade), stock 799 valves, stock seats, LS7 lifters, and around 0.080" preload with 7.425" PR's. I didn't even have the heads checked, they came off of a truck with about 60K on them and all I did was degrease and slap them on. Something else is up, IMO.
10-06-2011, 12:18 PM
#26
I don't think it's the high lift and double springs. I can't offer an alternative diagnosis but I have been running the MS4 (239/242 0.649"/0.609" 111+1 LSA) with bone stock 799 heads and 0.650" double springs for 20K miles and I have about 5-7K miles on my 0.675" double springs without issue. Stock rockers (with Comp trunnion upgrade), stock 799 valves, stock seats, LS7 lifters, and around 0.080" preload with 7.425" PR's. I didn't even have the heads checked, they came off of a truck with about 60K on them and all I did was degrease and slap them on. Something else is up, IMO.
10-06-2011, 12:52 PM
#27
i wasnt asking about the age of the double springs because i think they cracked the intake valves... I was asking about the valve springs because,,, if the OP put in used valve springs (and didnt check the seat pressure of the springs and shim accordingly) and it was all fine and dandy for 5,000 miles maybe the springs lost some tension and now the valves are floating a slight bit... if the OP has a very tight PTV clearance, which it sounds to me like he does, then a tinny bit of float could cause the valves to just slightly kiss the piston... also the 243 heads have smaller combustion chambers than the 241 heads but they both have roughly the same PTV clearance, if you mill the 241 heads to get a smaller CC then you could be looking at issues regardless of what a cam manufacturer told you, no matter how reputable that cam manufacturer might be.
Earlier in the thread, someone thought high lift and double springs. That is what I was referencing.
10-06-2011, 01:53 PM
#33
Yes, I recently did the trunnion upgrade and they were good then, maybe 2-3K miles ago. I plan on upgrading to a Katech C5R chain with a new o-ring and front seal, I am going to check again. My VT is relatively quiet but amplified by the fact that I drilled a 1" hole in the firewall right behind the DS head for sensors, wiring, etc.
10-06-2011, 02:49 PM
#35
Anyone think this could be an oiling problem? I had no obsessive valvetrain sounds until this slight ticking began a few days ago. It only happens after the engine gets warm and comes and goes during regular driving. At idle my oil pressure is around 45 when cold and drops to 28 when warm and usually runs at 40 at cruising speed.
10-06-2011, 07:39 PM
#39
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I hope not. After reading OP's post's I'm thinking it has something to do with the high lift on the intake side and have to much preload on the lifters. That setup is tight already with that much preload on the lifters and than you throw .650 lift on it at high rpm that just might put to much presure on it and chew the tips up. You have to think it has something to do with the high lift when it's only the intake side with the problem. Your probably going to have to replace the valves! Especially sense your still driving it like that? And when you do replace the valves I would set preload alot less. About .080 or so...
10-06-2011, 07:53 PM
#40
Are those the stock rocker arms? Whatever they are, they must be super hardened on the contact area at the tip.