monte70car Posted May 27, 2012 Share Posted May 27, 2012 the car kinda breath fire this afternoon but I can't stand the dam popping in the exhaust at 2k for more then a minute I did grab this video and I think the new cam is a little quitter then the old cam. I think the popping is lean but standing behind it, it will make you cry so I don't know. Valves were doing with turning the push rod until it couldn't turn then backed off so I don't think its a valve that's to tight. Maybe some of you engine guys can tell. The starting if slow which I believe is in the injection system, the funny noise is the fly wheel as it's missing teeth got a replacement in the garage. Quote Link to comment Share on other sites More sharing options...
72MC Posted May 27, 2012 Share Posted May 27, 2012 Rob, the new gauges look real nice. Can't help ya with the popping. However, I will say, when I first starting hearing it in your video, it sounded a little like someone was getting slapped . Thought maybe your dad was tired of your antics or something . - Dave Quote Link to comment Share on other sites More sharing options...
7tonemonte Posted May 27, 2012 Share Posted May 27, 2012 Im with Dave, sounded like some slaps I like the gauges alot Rob, get the issues ironed out, leave that poor car alone and drive and enjoy it. Quote Link to comment Share on other sites More sharing options...
overdrive Posted May 27, 2012 Share Posted May 27, 2012 I gotta say I've never heard of adjusting valves that way. Most cam manufacturers recommend setting hydraulic lifters to 0 lash with the lifter on the base circle and then somewhere around 1 turn tighter, depending on the maker. Quote: Valves were doing with turning the push rod until it couldn't turn then backed off so I don't think its a valve that's to tight. You say you backed them off, but how much? Dan Quote Link to comment Share on other sites More sharing options...
bigtankjones Posted May 27, 2012 Share Posted May 27, 2012 Dash looks good. I'm not a fuel injection Guy. Wish I had some Ideas For you. Quote Link to comment Share on other sites More sharing options...
monte70car Posted May 27, 2012 Author Share Posted May 27, 2012 Dan that method is in my Chilton book out in the garage. they have you turn the push rod until you can't turn it and then back it out a 1/8th of a turn. I know if its to lose it will chatter away. The paper work on the cam says 0 lash. I got the oil PSI issue figure out just have to pull the dash pad and double check. Quote Link to comment Share on other sites More sharing options...
Sam (Bones) Posted May 27, 2012 Share Posted May 27, 2012 you tighten the rocker nut to zero lash, then usually another half turn, most hydraulic lifters call for .030-.050 preload, half turn on a 7/16" fine thread stud usually comes in at just over .030 Quote Link to comment Share on other sites More sharing options...
Mr70Monte Posted May 27, 2012 Share Posted May 27, 2012 I always adjust them by tightening the nut until there is no more pushrod movement up & down (thats zero lash) then 1/4 turn tighter, never have had a problem. btw, you better get it right, you want that engine to fire up as fast as possible, it doesn't take long to damage a new cam. then 2000 rpms for 15-20 minutes, no idle time (unless its a roller cam) Quote Link to comment Share on other sites More sharing options...
monte70car Posted May 27, 2012 Author Share Posted May 27, 2012 I'm not touching it until I get the starting and the popping resolve. Quote Link to comment Share on other sites More sharing options...
Sam (Bones) Posted May 27, 2012 Share Posted May 27, 2012 the popping could be your valve adjustment! Quote Link to comment Share on other sites More sharing options...
Montemedic Posted May 27, 2012 Share Posted May 27, 2012 Did you recheck your spark plug wiring firing order? Quote Link to comment Share on other sites More sharing options...
Mr70Monte Posted May 28, 2012 Share Posted May 28, 2012 unless thats a roller cam, your killing it letting it idle...... Quote Link to comment Share on other sites More sharing options...
MGD72Monte Posted May 28, 2012 Share Posted May 28, 2012 Nice dash, unusual sound, never heard that before. Did you just change the valvetrain or something else. As per others on the valves, I also have never heard of that type of adjustment but each cam seems to have its own. My Comp Cam called for 0.030"+/-.010 preload achieved by tightening the nut while spinning the pushrod with finger tips until a slight resistance in the pushrod (0 lash) then turning the nut 1/2 turn more. Hope you find the issue. Ditto on what others have said about the need to get the revs up to break in the cam properly. Good luck Quote Link to comment Share on other sites More sharing options...
monte70car Posted May 28, 2012 Author Share Posted May 28, 2012 With the popping in I did not go pass the 2000-2500 break-in for 20 minutes plus I was not getting an oil psi. I believe the route cause of the popping was due to the o2 sensor not sealing good. I have since welded the o2 sensor to the lead pipe but have not try to finish the break in today or even see if welding the of the o2 took care of the popping. Quote Link to comment Share on other sites More sharing options...
TrunkMatt Posted May 28, 2012 Share Posted May 28, 2012 Popping / Backfiring out the rear is usually a sign of too rich as unburned fuel is combusting in the exhaust. Popping / backfiring out Carb = Lean condition, combustion before compression. If you got your O2 gauge hooked up right, and your tuning correct - your O2 should be reading between 12.5 (rich) and 15 (lean) at idle... probably cycling between. They say 14.7 is perfect, but at idle you want to be a bit on the rich side. Also - throw on a vacuum gauge and tell us what the gauge reading is doing when it pops. Does it take a nose-dive? Quote Link to comment Share on other sites More sharing options...
Andy's Auto Posted May 29, 2012 Share Posted May 29, 2012 The first thing that comes to mind with the popping is an exhaust valve adjusted too tight. It can be tough adjusting them the first time if they are new or at the very least collapsed. Pull the covers, throw a starter button on it and first make sure you didn't wipe a lobe out and the readjust them all and see if the pop dissapears. Quote Link to comment Share on other sites More sharing options...
monte70car Posted June 5, 2012 Author Share Posted June 5, 2012 Well I got the cam broke in this afternoon. Once I got the cam broke in I lose fuel PSI .2% last long enough to beat the clock before it die. Once it cut off the interior started to smoke, pulled the back seat out and the floor broad above the mufflers were hot. It looks to be fuel that's not burned gets in the mufflers and re-lights causing the popping. Quote Link to comment Share on other sites More sharing options...
TrunkMatt Posted June 8, 2012 Share Posted June 8, 2012 I rest my case on my previous statement. Now you just need to figure out why that much fuel is dumping... it honestly doesn't take much to make your exhaust get orange-hot - I know when I was first tuning my 383 w/ 670 Holley, I was rich and my whole exhaust system was glowing from the headers back. It only took about 4 jet sizes down to correct (about 15% change in fuel). hopefully you didn't burn out your Wideband AFR gauge if you installed one in teh exhaust. Quote Link to comment Share on other sites More sharing options...
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