text: Arrrrg! Smoked the cam. - Team Camaro Tech
  Team Camaro Tech > First Generation Camaro Info and Tech - 1967- 1969 "Where it all started" > Engine > Arrrrg! Smoked the cam.
  post #1 of 19 (permalink) Old Jun 16th, 15, 07:45 PM Thread Starter
  Arrrrg! Smoked the cam.
  Pretty close to complete with the resto. 396, 500 miles on a fresh rebuild. Started stumbling and missing. Chasing the cause, found blown intake gasket, a pan full of oil-antifreeze milkshake, 4E pushrod in a mr pretzel form, 4I pushrod tip beat off, and about all lobes (but cylinder 4) wiped. Only thing I can think of is prior to all this I ahd a big backfire while starting up (had been sitting a while and was pumping gas into dry carb). Glad it's summer, makes the beer taste better while cleaning up this mess.
  post #2 of 19 (permalink) Old Jun 16th, 15, 09:00 PM
  Re: Arrrrg! Smoked the cam.
  With you forensics it hard to tell what broke 1st.
  post #3 of 19 (permalink) Old Jun 17th, 15, 01:01 AM
  Who built the engine what cam brand and model number also what lifters and motor oil was used. Alex
  post #4 of 19 (permalink) Old Jun 17th, 15, 06:35 AM Thread Starter
  My build with some local machine work.
  Cam was a Crane2030. Going back with a Lunati.
  With the #4 cylinder clean lobes and those pushrods both messed up, I'm thinking it has to be the backfire popped the gasket and the pushrods (not sure i believe this yet), then antifreeze in oil smoked the cam. Both 4E and 4I lobes are fine. The rest are pretty much wiped. Oil was originally Val 10/30. Lifters were Comp. Springs came with cam.
  Backfire wasn't anything huge, but not normal. Car had been sitting in shop for a few weeks. Has/was running fine prior to this. After a few weeks, the gas evaps from carb, so I'm pumping and turning over to get fuel to carb...backfire.
  post #5 of 19 (permalink) Old Jun 17th, 15, 09:20 AM
  Odds are the cam went flat first. What kind of break in procedure/lube did you use when you first fired the engine?
  post #6 of 19 (permalink) Old Jun 17th, 15, 09:37 AM
  Not familiar with a Crane 2030 is it new stuff or old . They are supposed to be making excellent quality cams since S&S took them over . why would you use Comp lifters on a Crane cam ?Are these left over parts you had ? The 10 / 30 Valvoline was it VR-1 Silver bottle or regular ? Did you use a bottle of break-in lube. Did you slop up the lobes with any type of extreme pressure lubricant like Isky REV-LUBE. Like Brian said we need to know all these things . Alex
  post #7 of 19 (permalink) Old Jun 17th, 15, 10:51 AM
  Spring pressure is another factor; especially on break in. Flat tappets do not tolerate a lot of spring pressure now thanks to changes in the oil formulation. You can run ZDDP additive all the time to compensate, but even when these motors where brand new a flat tappet and a stiff valve spring was a recipe for a disaster.
  post #8 of 19 (permalink) Old Jun 17th, 15, 01:20 PM
  Crane was sold again last year.
  post #9 of 19 (permalink) Old Jun 17th, 15, 01:35 PM
  I would highly recommend going hyd roller. I have had many go this route with resto's.
  post #10 of 19 (permalink) Old Jun 17th, 15, 07:00 PM
  I went roller after losing 2 solid lifter cams. 1st lasted about 50k and the 2nd 8700 mi. The 2nd was broke in using my old springs with Joe Gibbs BR oil. Joe Gibbs 10w-30 Hot Rod oil was used after the cam was worked for a few hundred miles then I changed the springs and broke in the springs the same way as the cam per Lake Speed Jr (Joe Gibbs Racing).
  post #11 of 19 (permalink) Old Jun 17th, 15, 07:16 PM
  IMHO the Joe Gibbs products are not the best.
  I've used Valvoline VR-1 and not had issues.
  There is no reason Flat Tappet Can Installations can not be successful.
  But yes if possible pony up for the rollers
  post #12 of 19 (permalink) Old Jun 17th, 15, 09:20 PM
  After using Joe Gibbs Hot Rod oil, I switched to Valvoline VR1 with a bottle of EOS. I still lost a lobe. It's today's crappy steal and hardening process they're using.
  post #13 of 19 (permalink) Old Jun 17th, 15, 10:20 PM
  Well now we have just learned from Chris Straub that S&S no longer owns Crane Cams . Just for that reason now I would not buy a cam from them .So what does that leave . you cant buy a Lunati they are owned by brand CC so that quality is gone . So for flat tappet cams you have Isky Howards Engle Crower Clay Smith and Schnieder. I have used the first three all excellent quality no problems . the last three I just don't know they do have excellent reputations for quality. IF I had the funds to go roller I would definatly go with a Chris Straub roller the list of smiling and happy customers is endless. I wish he sold a line of F / T cams I would buy one . Alex
  post #14 of 19 (permalink) Old Jun 18th, 15, 07:23 AM
  Most (but not all) of the automotive camshafts produced today are produced at one of the Big Three cam manufacturers all located in Michigan. CMC of Jackson, MI., Engine Power Components (EPC) of Muskegon, MI., and Waver Bartel Cam Company, of Grand Haven, MI.