SleeperZ Posted October 3, 2011 Share Posted October 3, 2011 (edited) Although I had my P90 professionally built years ago, I have less than 60-70 hours on this cam. I was checking and adjusting the valve clearances, and this showed its ugly face. Schneider turbo cam (Stage II from MSA, Lift .460/.460 Duration 270/260.) Intake #2 only has a rocker-wide wipe on the high part of the lobe, currently about 1/32" deep, and the clearance was good. All the rest of the lobes seem fine. But one is all it takes. Any successful installs of this cam? I'm sure it's statistically possible to get a cam with 12 good lobes.... Edited October 3, 2011 by SleeperZ Quote Link to comment Share on other sites More sharing options...
proxlamus© Posted October 3, 2011 Share Posted October 3, 2011 I ran this camshaft for some time! I used diesal engine oil, due to the high levels of zinc to maintain the camshaft life. That's so bizarre that one lobe is messed up! How bad was the valve clearance? Quote Link to comment Share on other sites More sharing options...
Tony D Posted October 3, 2011 Share Posted October 3, 2011 The face is blue, which indicated overheating, likely due to either lubrication breakdown, or lack of oil. This would have me looking closely at the lubrication at that lobe before jumping to Schneider. It is also possible that ZDDP not being added to the oil is a culprit as well. Is this a "CWC" or "JAPAN" blank? Talking with some cam people, they tell me that the CWC actually is metallurgically a 'better' cam stock, than the Nissan blanks but for some reason the CWC's seem prone to failure with todays oils lacking the high Zinc content. For the record, I've seen multiple cam lobe failures on Nissan Cams (stock) as well, almost always due to plugged lube spray holes. Bummer, good luck on the re-cam. Quote Link to comment Share on other sites More sharing options...
johnc Posted October 3, 2011 Share Posted October 3, 2011 Lube problem. Quote Link to comment Share on other sites More sharing options...
SleeperZ Posted October 3, 2011 Author Share Posted October 3, 2011 (edited) I have run this head twice, once on the original block, and now on the current block. I don't know when the lobe first failed, either the first install or the second. I've always run Mobil 1 synthetic in it, and both times I installed it, it was well lubed with assembly lube. But I never thought to ever run ZDDP additives. The valve clearance was actually ok, the back side of the lobe was normal. The first picture I see the blueing indicating overheating/lack of lubrication, but the second shot, close up, the exposed metal under the heat-treatment is shiny silver. So I'm not sure if the blueing is not a photographic effect or not. The unworn part of the lobe looks exactly like the rest of them. So if it's not a heat-treating issue (seems unlikely on just one lobe), there could be a plugged oil passage in that lobe. It also would be unlikely that number 2 intake valve is limited in it's travel, although that condition probably would not have lasted past initial startup without breaking. Just thinking out loud. The head was originally built with all new components, valves, springs, pads, rockers, etc.... I appreciate the discussion. When I decide to rebuild this puppy, I'd like to keep the valves and springs, and just replace the cam, rockers and lash pads. Am I correct in thinking I cannot get a replacement cam with more lift than the Schneider at .460/.460 without different valve springs? Oh, and I have no idea what blank the cam was manufactured from, it came from MSA more than 10 years ago.... Edited October 3, 2011 by SleeperZ Quote Link to comment Share on other sites More sharing options...
SleeperZ Posted October 3, 2011 Author Share Posted October 3, 2011 Oh, on second look, I see the blueing on number 1 exhaust, not on the worn lobe....I suppose that is another indication of insufficient lubrication? Quote Link to comment Share on other sites More sharing options...
JMortensen Posted October 3, 2011 Share Posted October 3, 2011 .460 is about the limit on the stock springs, kinda depends on how far the valves and seats are cut and installed heights after that. Schneider makes nice springs that aren't super stiff and will handle a lot more lift. There is a common Ford 2.9L V6 valve stem seal that works, it is Fel-Pro #SS72686. With those parts you can run .600 + lift without any binding issues. Losing a lobe does seem to be a pretty common issue with the Schneider cams for whatever reason. I would go with a regrind, and maybe add a spraybar as well. Not sold on the ZDDP, but a bunch of others are. Quote Link to comment Share on other sites More sharing options...
ZR8ED Posted October 3, 2011 Share Posted October 3, 2011 With high RPM and hp levels, I tried to minimize the risk of excessive wear and tear by running a hollow cam setup AND a spray bar for extra insurance. (I've had good success with Shneider cams in the past) Quote Link to comment Share on other sites More sharing options...
madkaw Posted October 3, 2011 Share Posted October 3, 2011 5000 + miles on my schneider cam and it looks perfect. I have read of cams that the holes were not drilled through properly. And I have tested running both hollow camAND spray bar and it didn't work as well as you think. The hollow bar takes to much pressure or volume away from the spray bar and the oil never sprays far enough to do any good. I also run additive with very oil change Quote Link to comment Share on other sites More sharing options...
SleeperZ Posted October 3, 2011 Author Share Posted October 3, 2011 Did some searching on a crazy idea, can't find any information at all; there is probably a good reason. But anyway, assuming the rest of the cam is OK, can the one bad lobe be repaired so I only have to replace one rocker? Just askin' Quote Link to comment Share on other sites More sharing options...
SleeperZ Posted October 3, 2011 Author Share Posted October 3, 2011 Losing a lobe does seem to be a pretty common issue with the Schneider cams for whatever reason. I would go with a regrind, and maybe add a spraybar as well. Not sold on the ZDDP, but a bunch of others are. I see that Web Cams offers a variety of re-grinds. Is that something that can be done with a used, but otherwise good cam shaft, say from my old stock turbo head? If so, can the original rockers be re-surfaced instead of paying MSA $38 per rocker? My cheapest option at this point is to replace my head with my spare P90, stock cam. I really don't like the stock cam and how it runs out of breath before 6000 rpm, unlike the Schneider or the original 240Z cams. So maybe that factory turbo cam could be re-ground to something that spins nicely to 7k... Quote Link to comment Share on other sites More sharing options...
Zmanco Posted October 3, 2011 Share Posted October 3, 2011 Delta cams resurfaces rockers for about ~5 each. Quote Link to comment Share on other sites More sharing options...
JMortensen Posted October 3, 2011 Share Posted October 3, 2011 Delta, Web, and Isky offer regrinds, among others. No doubt you could get something that would spin up to 7K. Quote Link to comment Share on other sites More sharing options...
CamH Posted October 4, 2011 Share Posted October 4, 2011 I am now running the same cam. I heard about this issue, with the Schneider CWC cores, so I sent my cam off to be nitrided prior to installing it. I only have about an hour of usage on it so far, and have already inspected it once (it is fine), but I do plan on checking the cam for wear the next time I change the oil, in a few months (I do not drive the car often). I run Royal Purple 10-30w in my engine, which is a high ZDDP oil, to my understanding. I'll try to post back if I see anything unusual. Quote Link to comment Share on other sites More sharing options...
Tony D Posted October 4, 2011 Share Posted October 4, 2011 And I have tested running both hollow camAND spray bar and it didn't work as well as you think. The hollow bar takes to much pressure or volume away from the spray bar and the oil never sprays far enough to do any good. That should not be the case, you have either not enlarged the delivery passage in the block as required, have excessive bearing wear on the bottom end resulting in excessive demand there, or run a pump of insufficient size/spring relief pressure to do it. An Auto-Turbo oil pump will have MORE than enough flow to absolutely FLOOD the top end with a dual lubrication system.So will the stock pump if the bottom end bearings are in decent shape and not throwing off a lot of oil from excessive clearances. I have left off the obvious "the plug is in the back of the cam" as a reason for what should be clear reasoning to everyone. Quote Link to comment Share on other sites More sharing options...
SleeperZ Posted October 4, 2011 Author Share Posted October 4, 2011 I emailed Delta Camshaft, and they said they can repair and re-grind the cam, and supply reground rockers for $3 each with a $3 core. Total is less than $150. Doesn't sound bad at all. Aside from the potential lubrication issues, and possibility of new lash pads, does this sound like a viable option? Quote Link to comment Share on other sites More sharing options...
duragg Posted October 4, 2011 Share Posted October 4, 2011 I wonder why that one went away to begin with? When I got my regrind from Isky they said absolutely no need to heat-treat or harden afterwards. For me I drive so little and was in a hurry so I went with their professional opinion. (old stock regrind). Since you had a problem once it might be worth a few bucks for a day at the heat-treat shop? Quote Link to comment Share on other sites More sharing options...
SleeperZ Posted October 4, 2011 Author Share Posted October 4, 2011 With high RPM and hp levels, I tried to minimize the risk of excessive wear and tear by running a hollow cam setup AND a spray bar for extra insurance. (I've had good success with Shneider cams in the past) To install the spray requires cam tower replacement with parts from an E series head, correct? Quote Link to comment Share on other sites More sharing options...
madkaw Posted October 4, 2011 Share Posted October 4, 2011 Tony My experiment was on a fresh rebuild with the block oil passage enlarged. The only fault in my experiment was the fact I used a drill to turn the pump and that might not have been enough rpm to apply enough pressure-2800. I did verify pressure with a guage and visually verified the spray bar oil not reaching the folowers. This was a high pressure pump. I had a thread on classiczcar documenting this Quote Link to comment Share on other sites More sharing options...
JMortensen Posted October 4, 2011 Share Posted October 4, 2011 To install the spray requires cam tower replacement with parts from an E series head, correct? Yes, and don't listen to people who tell you that you can't swap cam towers. Just number the towers before you remove them, install them in the correct order and make sure the cam spins freely after they're torqued. I would regrind a stock cam. If you don't have one, email my bro-in-law at mat m AT m2differentials.com. He has probably 10 cams loose in his shed. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.