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Cam failure ?

2K views 13 replies 8 participants last post by  bowtieorbust 
#1 ·
Man that post about (Unexplained cam failure) knocked me for a loop, i'm really wonder'in if i should take the leep of faith and break-in the High Energy 268H Comp Cam that i have for my 350sbc. When i perchased the head's they were bare and needed the valve's and the spring's, i then got valve's and a set spring's from the local speed shop that i believe are good for up to .500 lift wich are a little different than the one's that World Product put's on there S/R Torquer head's wich i believe are good for up to .560 lift. My ? is what are the chances that this cam failing on me and rounding off any of the lobe's after an ample amount of molly past is applied to the cam and the lifter's, plus use'ing a nonsynthetic oil with the EOS from GM, plus stick a zinc additive in there to boot, the thought of changeing everything over to a Retro-fit roller set up is out of the ? for now because of budgit reason's. I guess what im look'in for is boost of confident's because i've got $160.00 in the cam and lifter kit, around $30.00 in the push rods, and around $125.00 raped up in the spring's and retainer's. Yea i know a roller set up would cost around a grand :pain: :eek:. Thought's Please:thumbup:
 
#3 · (Edited)
I installed the Comp 262ex in my 350.After hearing a string of bad news from other Comp owners I got all paranoid and befor I evan fired the motor allmost bought a Crane.
Well anyway I did keep the cam but decided to puller out and clean it in brakleen and replace that crappy red lube(which had dripped off)that Comp supplies and relube it w/ Crane moly(gray stuff)lube.Well I only had the motor running a few days befor I found a soft spot in the montes frame and pulled it,but its was good so far.
I think allot of Comps failures are due to the crapp redlube,there Tech told me that the motor must be fired within days of that crap being applied or it drips off.And yes it was all in my oil pan when I pulled the cam out.
I used Z28 springs on my heads. If you got .500 lift springs on the 268H I think you'll be OK.ut I'd feel better with like a .480 lift spring myself.Maybe call Comps tech line.
Also do there recomended breakin.Adjust the valves beforhand and fire it right up and bring up the Rs to were they want um(2000 or so). I've done a few cheapy cams by fireing them and adjusting the valves wet and no break in(befor I knew about it),I think the good lube saved me,but who wants to chance it on a $200 cam kit.
 
#4 ·
with normal springs the chance of your cam failing are slim and none. Don't believe the drama, peopel talk about the two cam failures they had (which were probably their fault anyway) when they have built like 500 motors. Don't lose sleep, put in a bottle of break-in concentrate, use some 30WT valvoline and don't worry about it



K
 
#5 ·
Thanx guy's for your suport :thumbup: I feel as if im on an epesode of fear facter, I mean all the talk about checking the crown on the lifter's, and how hard the cam core is enough to make one's head spin. :sweat: A buddy of mine installed a Lunati cam in his 305 sbc, with the week stock spring's and a small amount of Lunati's lube on the cam, he just started the engine and ran it long enough to set the timing by ear and shut it down with out any 20 min. break-in, and i guess to this day it's doin ok.So i guess i'll pull out all the stop's and go for it.:thumbup:
 
#6 ·
cam

Killer,

I can't speak for the others but i don't post for the drama factor....(I am sure they don't either)

I don't want to make anyone scared to install a cam, but i do wan't them to be informed. I could hardly stand it to watch someone destroy a part if i could offer some simple advise to stop it from happening....

I doubt that any of the accomplished engine builders that visit here have wiped out a cam because it "was there fault" ( after they had the knowledge of why cam's go bad) Most builders take great pride and care to build the best engine they can and to avoid all the pit falls along the way.


Bowtie,
With a cam that mild you will be ok. Like killer stated use the breakin lube(i prefer gm's eos) use a good molly paste on the lobes and lifter bottoms, straight 30 weight oil,make sure the carb is full of gas and the timing is set correct so the motor fires right away. Run it at 2200 rpm's or so, (rev it up now and then to re direct the oil splash) for at least 20 minutes.
 
#7 ·
I agree fully with k-star. When you've been building engines for a while without any failures, then all of a sudden have a couple of cams in a row go flat in different engines. I don't believe it's because you've forgotten how to do it. If you have one go flat then I'm sure the next one got double the attention.
 
#8 ·
yes cams can go flat. And you can spin a rod bearing on startup, or crud can block and oil galley or crack a weak block or any number of things. There's no reason to over-advertise it, and I think this site does. We're making people shake in their boots about flat tappet cams and they've worked great for years. Yes there is a chance of them going flat, just as there is a chance of many other things. Fact of the matter is its not that common of an occurrence. ANother fact is that (ok, probably not for experienced builders) most cams DO GO FLAT due to incorrect install or break-in. ANy manufacture will tell you that-

K
 
#11 ·
Also Comp says you don't have to,but I still soak my lifters in oil for a while.Also prime the motor and if your really paranoid you could turn the crank in several positions by hand while doing it to splash differant points of the cam(if your really paranoid :D)
Use the grey moly lube though.IMO that comp red lube is only good as cherry sauce on ice cream.
 
#12 ·
Fill the crankcase with 9 or 10 quarts for extra splash !!!!!!!!!!!
I didn't know SBC used a splash system!!!
 
#13 ·
solidaxel said:
Fill the crankcase with 9 or 10 quarts for extra splash !!!!!!!!!!!
I didn't know SBC used a splash system!!!
ha ha ha, are you kidding? How long has it been since you had one apart? The crank picks up bunches of oil and splashes it on the cam as it misses the cam by a fraction of an inch...:rolleyes:

Actually, is there any V8 that doesn't use a splash system?

K
 
#14 ·
With all the worry about the oil not containing enough zinc or phosphorous for break in, and even though the break in goes well, will there still be a problem with the synthetic oil's not containing enough zinc or phosphorous, to whare i'dd have to stick the E.O.S additive in the oil every time there's an oil change done. :confused: :thumbup:
 
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