Camshaft help

[jason79]

So, I put together a 512 stroker this winter/spring. 440 Source kit. The idea was to build a solid bottom end that I could upgrade as funds allowed. That being said I used the stealth heads with my stock valve train. I reused my mopar 509 cam from my old engine. Before installing the cam, I disassembled the lifters and cleaned them out . Installed the cam with assembly lube, primed the oil system (high volume oil pump). I performed engine break in just like normal. 20 minutes run time RPMs 2000 to 2500 varied. Valvoline 10w30 racing oil (high vinc). After 1 trip to town and back , I heard a lifter tick. Pulled the valve covers, to find a loose push rod. Pulled the intake to find a rounded cam lobe, number 6 exhaust. ****.
Time to start over. I purchased a lunati voodoo cam and lifter kit. Installed with a ton of assembly lube, new valvoline high zinc and Napa gold filter, comp cams break in additive. Broke it in exactly as the instructions called for. 1 trip to town and back and there was a lifter ticking again. Pulled everything again only to find a rounded lobe number 4 intake . WTF! What am I doing wrong! This is getting expensive! I'm about ready to give up on hydraulic flat tappets. FYI this is nowhere near my first engine or camshaft swap. Ideas? Is it time to bite the bullet and do adjustable rockers and a roller cam?

 

[moparedtn]

WAD: Perhaps there's an oil circulation issue? Sounds like that part of the valvetrain is starving for oil perhaps?

 

[jason79]

WAD: Perhaps there's an oil circulation issue? Sounds like that part of the valvetrain is starving for oil perhaps?

From what I see the oil flow is good. Heads both oiled great when priming the engine, both times. Everything is covered in oil when I pulled the valley pan. Oil pressure is 75-80 cruising, and 55-60 at hot idle.

 

[jason79]

Also there is no wear on any of the other lobes, or lifters, of either cam. Outside of the ones that are rounded.

 

[493 Mike]

I wiped out a cam also. It turned out to be misalignment of the lifter bores machined by the factory. The condition did not show up with the stock cam as it was so mild. I sent the cam to Dave Hughes (his cam) and he diagnosed the problem. I had the lifter bores machined to straighten and bushed back to size-problem cured. As a side benefit a small slot was machined in the bushings for tappet lube and even if a lifter jumps out of the bore the engine will not lose all oil pressure.
Mike

 

[wyrmrider]

Darn- so many things
Do not add ZDP to SN oil makes it worse not better, get the right oil pre blended
stuck/ sticking valve (s)
worn out lifter bores (after writing this Mike posted now above)
pull the valve covers
rotate the engine over twice with a breaker bar 1/4 turn at a time and inspect each valve gear- pushrods spin when they should
did you way what lift is? did you do the half lift geometry? too much angle on the rockers can do it- what rockers? (not as much chance of binding with roller rockers)
you can grind a flat on the lifter use a magnetic chuck and a v block on a surface grinder- get a buick v6 lifter for a pattern they did this stock

 

[oldkimmer]

U have too much spring pressure is my guess. Kim

 

[jason79]

I'm just guessing here. The first cam went along for the ride on my other engine that ate 2 rod bearings. It is possible that it could have been damaged then. Nothing appeared wrong to the naked eye. The second cam no idea. The rockers are the stock stamped steel, in great condition. It is possible i have a geometry issue with the new heads. Spring pressure us 130 seat 330 open, which is what lunati recommended for this cam.

 

[451Mopar]

I would run the Hughes Engines Lifter burnishing ball through the lifter bores to make sure they are round and the lifters rotate easy.
http://www.hughesengines.com/Index/...rcw==&level1=TGlmdGVyIEJ1cm5pc2hpbmcgQmFsbA==

 

[moparedtn]

It could also be pushrods are too long?
If the heads and/or block have been decked, stock pushrods will be too long afterwards.

 

[jason79]

It could also be pushrods are too long?
If the heads and/or block have been decked, stock pushrods will be too long afterwards.

I think you may be on to something there. The block has not been decked, but who knows with these aftermarket heads? Either way the new cam will have adjustable rockers, properly measured for push rod lenght. I don't think the lifter bores are the issue, as the block was from my original engine and the 509 cam lived in there for thousands of miles with no issues. The only thing that changed was the stealth heads, so it almost has to be a push rod or geometry issue.

 

[moper]

How are you pre-oiling the engine? How much are you turning it over before it's fired? Do you use the starter to fill the carbs too? As was asked - was lifter rotation verified during assembly? What break in material is used on the lobes and lifter faces? The fact that you have different lifters failing hints it's not the bores. I'm more inclined to say its something you are doing or not doing...

 

[BSB67]

So, I put together a 512 stroker this winter/spring. 440 Source kit. The idea was to build a solid bottom end that I could upgrade as funds allowed. That being said I used the stealth heads with my stock valve train. I reused my mopar 509 cam from my old engine. Before installing the cam, I disassembled the lifters and cleaned them out . Installed the cam with assembly lube, primed the oil system (high volume oil pump). I performed engine break in just like normal. 20 minutes run time RPMs 2000 to 2500 varied. Valvoline 10w30 racing oil (high vinc). After 1 trip to town and back , I heard a lifter tick. Pulled the valve covers, to find a loose push rod. Pulled the intake to find a rounded cam lobe, number 6 exhaust. ****.
Time to start over. I purchased a lunati voodoo cam and lifter kit. Installed with a ton of assembly lube, new valvoline high zinc and Napa gold filter, comp cams break in additive. Broke it in exactly as the instructions called for. 1 trip to town and back and there was a lifter ticking again. Pulled everything again only to find a rounded lobe number 4 intake . WTF! What am I doing wrong! This is getting expensive! I'm about ready to give up on hydraulic flat tappets. FYI this is nowhere near my first engine or camshaft swap. Ideas? Is it time to bite the bullet and do adjustable rockers and a roller cam?

Did the same lifter go back on the same cam lobe on the re-used 509 and lifters?

 

[Challenger340]

I'm just guessing here. The first cam went along for the ride on my other engine that ate 2 rod bearings. It is possible that it could have been damaged then. Nothing appeared wrong to the naked eye. The second cam no idea. The rockers are the stock stamped steel, in great condition. It is possible i have a geometry issue with the new heads. Spring pressure us 130 seat 330 open, which is what lunati recommended for this cam.

IMO, 330# open pressure is not a good idea to run a flat tappet cam in.... no matter HOW much Zinc or any Oil used !

We NEVER exceed 280#.... to 300# absolutely MAX "over the nose" running in a Cam on the Dyno.
You may wish to contact Lunati themselves and ask them ? But I think they may tell you the same thing for Cam break-in, no matter the rec'd "over the nose" pressure once done.
If LUNATI says "OK" to run the Cam in at 330# over the nose..... ask for WARRANTY ! and see how their tune changes !

 

[jason79]

Did the same lifter go back on the same cam lobe on the re-used 509 and lifters?

I have some questions on that too. I had everything in order, but did have a buddy helping assemble the engine. He knows what he is doing also, but it wasn't my hands that installed all the lifters. So it is possible he mixed 2 up?

 

[jason79]

How are you pre-oiling the engine? How much are you turning it over before it's fired? Do you use the starter to fill the carbs too? As was asked - was lifter rotation verified during assembly? What break in material is used on the lobes and lifter faces? The fact that you have different lifters failing hints it's not the bores. I'm more inclined to say its something you are doing or not doing...

Everything was assembled with plenty of assembly lube, on all surfaces. Valvoline high zinc oil. Comp cams break in additive for flat tappet cams. Engine primed with drill, while rotating 2 full revolutions, to verify oiling. I install distributor with rotor set at 12 degrees advanced. Carb was gravity filled, then gas line was hooked up. Like I said not my first engine rebuild. I just made a wrong assumption not verifying that the stock valvetrain would work.

 

[wyrmrider]

half inch or 550 valve lift works fine with stock lifters unless
base circle is reduced and longer pushrods are not used
wrong pushrods
with 550 I used to use lash caps
half inch (not much more than stock) some thin shim stock to get geometry right at half lift
stock stock rockers (not the HD ones will push the pushrods thru the cup with too much spring pressure
use LA/AMC lifters and oil through the pushrods- (either hyd or solid but pushrod cups are different heights so check)
if using iron rockers use hard chrome shafts or case hardened shafts (required with roller trunions)
Iron rockers or roller rockers use adjusters with cup and use ball and ball pushrods
high rate springs run larger pushrod "balls" (Ford size)
long pushrods- use heavy wall on everything and 3/8 if much rpm or spring pressure

 

[supercommando70]

Take the inner spring out when running in , also before you start make sure all lifters are turning in the bore leave the intake off and put a vivid mark on all lifters then rotate and you will see , depends o the cam some might be slow to turn compared to others ...as long as they turn should be all good . if one not look at that maybe to much preload .