280zex Posted September 9, 2013 Share Posted September 9, 2013 (edited) My Z finally hit 10k miles since the head rebuild, so I decided to give the valve train a check up.. N42, mild port n polish, stock deck height, Delta camshaft regrind on stock F / E30 solid cam, 280deg @ .480 lift measured at the lash pad. #160 lash pads. Stock spray bar. custom ss valves and seats, stock valve springs, guides, re-surfaced rockers from Delta, stock cam gear/chain/guides, cam chain/gear set on #2 hole. Ran 30w dino oil for 500 miles. Re-set rocker arm to lash pad clearance to 0.08 inch, ran another 500 miles on 30w oil. Re-set valve clearance to 0.08 inch on a hot engine, changed oil to Mobil-1 0w30 full synthetic, now at 10,000 miles. Checked the rocker arm to lash pad clearance and found 1 tight valve, #4 exhaust was at 0.07 inch. All others were where I set them, 0.08 inch clearance between the rocker arm to lash pad, with a hot engine. I noticed that the rocker to lobe wipe pattern is slightly off center on a few of the lobes, but only about 0.15 inch. Its not perfect, but I'm ok with that small of an off-set on the wipe patterns... Edited September 9, 2013 by 280zex Quote Link to comment Share on other sites More sharing options...
tooquick260 Posted September 9, 2013 Share Posted September 9, 2013 Looks good. Quote Link to comment Share on other sites More sharing options...
z-ya Posted September 9, 2013 Share Posted September 9, 2013 I would not run the Mobil 1 in a solid lifter engine. You better off running Valvoline VR1 conventional. It's cheaper too. The cam looks great BTW. Quote Link to comment Share on other sites More sharing options...
madkaw Posted September 10, 2013 Share Posted September 10, 2013 Nice to see a happy cam story ! Quote Link to comment Share on other sites More sharing options...
Jonathan Russell Posted September 10, 2013 Share Posted September 10, 2013 Yours is very similar to the head build I am working on now- Delta regrind with Delta rockers and 160 lash pads. Your cam looks good....except, as you said, for the offset wipe pattern. Why do you think this is happening? Did you use the stock retainers? If so, do you think the 160 lash pads are a tad tall for the stock retainers? Any valve train noise? I see you used stock springs. I am considering using Rebello outer springs.....mildly stiffer than stock. What was your thought process in keeping the stock springs? Thanks... Quote Link to comment Share on other sites More sharing options...
280zex Posted September 10, 2013 Author Share Posted September 10, 2013 I would not run the Mobil 1 in a solid lifter engine. You better off running Valvoline VR1 conventional. It's cheaper too. The cam looks great BTW.Why change oil brand when obviously the mobil1 works fine?? If there was a lubrication problem, it would have shown up by now. Quote Link to comment Share on other sites More sharing options...
280zex Posted September 10, 2013 Author Share Posted September 10, 2013 Yours is very similar to the head build I am working on now- Delta regrind with Delta rockers and 160 lash pads. Your cam looks good....except, as you said, for the offset wipe pattern. Why do you think this is happening? Did you use the stock retainers? If so, do you think the 160 lash pads are a tad tall for the stock retainers? Any valve train noise? I see you used stock springs. I am considering using Rebello outer springs.....mildly stiffer than stock. What was your thought process in keeping the stock springs? Thanks... No valve train noise issues, mostly stock components were used because my z is not a race car. I didnt see the need for hi-end components when i am not pushing the engines limits... As for the slight rocker arm to lobe wipe pattern offset, heck if I know?? That answer is for the valve train gurus to post about.... Quote Link to comment Share on other sites More sharing options...
skirkland1980 Posted September 10, 2013 Share Posted September 10, 2013 Your wipe patterns are off because delta does poor work. You have varying base circles from lobe to lobe. Quote Link to comment Share on other sites More sharing options...
skirkland1980 Posted September 10, 2013 Share Posted September 10, 2013 Are you taking about the pattern on the came lobe being on the edge? check to see if the rocker wear surfaces are parallel on the affected lobes. Quote Link to comment Share on other sites More sharing options...
Xnke Posted September 10, 2013 Share Posted September 10, 2013 Skirkland, you state Delta does poor work...I have yet to find any work they have done "poorly". I have found oversold cams, as they were sold using a 1.6 rocker ratio to advertise lift instead of the stock 1.46 ratio rockers...but poor work? Nah. 280Zex, if you are still using the stock springs, you might want to measure lift again. I have that same cam, but it's not 0.480" lift... it's 0.460" or so, once you take into account valve lash and rocker ratio. It's the max lift I would use on the stock springs, though, so not a big deal. Quote Link to comment Share on other sites More sharing options...
skirkland1980 Posted September 10, 2013 Share Posted September 10, 2013 Yes everyone makes mistakes but that's why you check your work. When you send someone an unusable item that's just bad business. Quote Link to comment Share on other sites More sharing options...
Lazeum Posted September 10, 2013 Share Posted September 10, 2013 Your wipe patterns are off because delta does poor work. You have varying base circles from lobe to lobe. To second Xnke, I've got a Rebello cam, base circles are not the same accross the entire shaft. I need different lash pads thickness to get proper pattern on cam lobes/rockers. Quote Link to comment Share on other sites More sharing options...
Xnke Posted September 10, 2013 Share Posted September 10, 2013 (edited) Skirkland, you don't seem to be running any Delta products, according to your "build log" signature...you claim stock internals. My Isky cam has different base circles from lobe to lobe, and the lobe centerlines are offset all the way down the cam...might be for a good reason! The long L6 cam twists from front to back...under load, the lobe centerlines all fall into line. Just because the base circles differ, doesn't mean the cam is bad. The lobe height may differ too, depending on who measures, how they measure, and what the base circle is for that particular lobe. Some cams are set this way on purpose; for example, the Delta cam I have has a slightly different profile for the exhaust as compared to the intake...and the base circle is 0.010" smaller in order to cut the lobe on the existing core. Also, valve jobs may be equalized differently...all might have the same tip height, might match just intakes and just exhausts, too. I've run both in the past. All of this changes your lash pad thickness. Edited September 10, 2013 by Xnke Quote Link to comment Share on other sites More sharing options...
skirkland1980 Posted September 11, 2013 Share Posted September 11, 2013 The problem I had with delta was, they told me my lobe lift was going to be .300" . What I got was .275". Had they simply checked their work they wouldn't have wasted everyone's time and effort. Secondly was the rockers. Two of them were cut with the wear surfaces not parallel. Also could have been caught before shipping out to me. Quote Link to comment Share on other sites More sharing options...
Xnke Posted September 11, 2013 Share Posted September 11, 2013 They oversold you the cam. They sell based on a 1.6 rocker ratio, not the stock 1.48. They didn't mis-cut anything...they just sold you more than you bought. Interesting about the rocker arms, though...I have 72 here they reground and every one of them is perfect. I have some more I might send in in a few months, I'll have to go through and check them closer. Quote Link to comment Share on other sites More sharing options...
madkaw Posted September 11, 2013 Share Posted September 11, 2013 I think everyone has to check their rockers for being parallel. My rockers were supposedly new with my Schneider cam kit, but my wear shows an unparrallel condition-and they were. Quote Link to comment Share on other sites More sharing options...
Leon Posted September 11, 2013 Share Posted September 11, 2013 (edited) FWIW, SIX of the 12 rockers I sent to Delta were not ground parallel. The rockers were done within the last 2 months. Edited September 11, 2013 by Leon Quote Link to comment Share on other sites More sharing options...
Tony D Posted September 11, 2013 Share Posted September 11, 2013 You want someone to tear up a cam grinder, talk to JeffP... He worked at Erson for years and finds little quirks in a cam profile and smiles "operator paused with the grinding wheel here before starting the cut!" And on it goes. Different lash pads aren't necessarily different base circle...which is damn hard to so using point of reference machinery today. But sinking your valves in the seats so slightly different and not trimming the stems for identical height will do that every time! Quote Link to comment Share on other sites More sharing options...
Gollum Posted September 15, 2013 Share Posted September 15, 2013 For a street, or even hot street head I wouldn't lose sleep over slight wipe pattern differences. Now, if I was revving the thing to 9k+ and making 300hp then I'd be worried that I didn't cover my bases. All in all I'd call this a happy cam story, and I wouldn't try to make it into something else. Quote Link to comment Share on other sites More sharing options...
srgunz Posted September 18, 2013 Share Posted September 18, 2013 Different lash pads aren't necessarily different base circle...which is damn hard to so using point of reference machinery today. But sinking your valves in the seats so slightly different and not trimming the stems for identical height will do that every time! Tony is correct. The valve stems should be measured and trimmed. That is how mine was done. Quote Link to comment Share on other sites More sharing options...
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