Hot Rod Forum banner
1 - 12 of 12 Posts

·
Registered
Joined
·
14 Posts
Discussion Starter · #1 ·
Hey gang, i have an 86 Monte Carlo SS with a newly rebuilt and balanced 355 sbc, dome pistons, 10.5:1 cr, vortec heads, comp beehive springs, lunati voodoo (flat tappet hydaulic) 504/525" lift 233/241 duration @ .050" lift cam, edelbrock intake and carb, etc..
My question is, with this same setup in a different 355 i ground 6 lobes on the voodoo cam within an hour. Now with this 355 balanced short block i bought, metal shaving are squirting with the oil out of the pushrods and rockers keep losening. I ran royal purple break-in oil for start up, i had 40-60 psi oil pressure, it has 30 minutes of run time and i am clueless. The first time i broke the cam in for 15 min at 2400-2800 rpm, this time i stayed around 1000-1500. From what i have heard these springs are compatible with vortec heads and higher lift than i am running.. i have plenty piston the valve clearance. please any advise will help. thanks
 

·
Banned
Joined
·
9,993 Posts
you used a really agressive cam and no oil additive... basically you wiped out one cam, and then continued to wipe out another. If you don't know how to maintain an agressive cam like that I suggest buying one of the "older" less agressive types and they are far more durable and are more forgiving.

VooDoo's are great IF you have everything down to the gnat's arse- sounds like you need something less agressive.

I hope your bearings aren't trashed... :pain:
 

·
Registered
Joined
·
14 Posts
Discussion Starter · #4 ·
I put the supplied camshaft assembly lube generously on the cam, and i used royal purple break in oil of the cam break in, which has all the additives like zinc and stuff. im thinking the spring pressure may be the problem but idk
 

·
Banned
Joined
·
9,993 Posts
If the springs were bought seperately you're probably right- those cams are REALLY picky. I won't touch them anymore, they're nice when they work, but they're a PITA to get to work.
 

·
Registered
Joined
·
14 Posts
Discussion Starter · #7 ·
yes, i adjusted on the stand to zero lash @ tdc plus 3/4 turn. then i was setting hot lash because they were clacking, that's when i noticed metal sparkles out of one of the push rods. i really cant imagine what would be doing this, does anybody know of any problems with beehive springs on vortec heads?
 

·
Registered
Joined
·
1,129 Posts
chewed camshaft

Hey bud, sorry you're having bad luck(I've been down that road before).Check out my recent thread in the engine section titled "Shell Rotella T". A fine fellow called "Huneycutt" posted a link to a video he created on proper camshaft breakin. Maybe it'll help you.olnolan :thumbup:
 

·
WFO
Joined
·
5,030 Posts
chevycarlo91 said:
From what i have heard these springs are compatible with vortec heads and higher lift than i am running.
There were articles written that said certain retainers intended for the Gen III engines were OK to use on Vortec heads, etc.

These articles were misleading and/or outright wrong. There are Comp retainers for Vortec heads using beehive springs, and there are retainers for Gen III heads using beehive springs. The problem is (in the case I'm citing) the retainers, not the springs.

The image shows the difference in installed height between the two retainers- the springs are identical.


#787-LEFT, for Vortec/non- GEN III heads; #774-RIGHT for Gen III heads
 

·
Registered
Joined
·
15,344 Posts
chevycarlo91 said:
Hey gang, i have an 86 Monte Carlo SS with a newly rebuilt and balanced 355 sbc, dome pistons, 10.5:1 cr, vortec heads, comp beehive springs, lunati voodoo (flat tappet hydaulic) 504/525" lift 233/241 duration @ .050" lift cam, edelbrock intake and carb, etc..
My question is, with this same setup in a different 355 i ground 6 lobes on the voodoo cam within an hour. Now with this 355 balanced short block i bought, metal shaving are squirting with the oil out of the pushrods and rockers keep losening. I ran royal purple break-in oil for start up, i had 40-60 psi oil pressure, it has 30 minutes of run time and i am clueless. The first time i broke the cam in for 15 min at 2400-2800 rpm, this time i stayed around 1000-1500. From what i have heard these springs are compatible with vortec heads and higher lift than i am running.. i have plenty piston the valve clearance. please any advise will help. thanks
These new high intensity cams are real touchy to break-in lube, break-in spring pressure and spring compatibility and even getting these things right might not be enough. Mechanically these super fast cams are right on the edge of the material strength, the slightest thing goes wrong and the cam is powder in the oiling system.

To start with the cam must use the manufacturer's recommended spring. There's a lot more to a spring than ultimate pressure. Springs have harmonic responses to the rate of lift, amount of lift, and frequency of lift (RPM) and the inertial weights they are trying to control. The frequency as established by engine RPMs, the inertial response established by RPM on component weights including the spring's weight both as an object and as separate coils result in different springs that may have otherwise identical pressures at closed or open positions to have unique responses to the applied forces. A mismatch of forces and speeds can cause the spring to go into harmonic surges and oscillations that hammer the daylights out of the connected components. Naturally should this occur the weakest link in the chain of parts will fail. These days it's usually the lifter/lobe interface on flat tappet cams.

So stay with matched parts, the manufacturer has done the tests and knows the response of their products, when you start cross pollinating valve train parts, you're really on your own. Some may work together many do not.

Bogie
 

·
Registered
Joined
·
14 Posts
Discussion Starter · #12 ·
Thanks for the help guys, i'm convinced it is somehow related to the spring pressure. i guess i will clean it up and try a new cam/lifters and springs. I really hope to get her running by the dream cruise.
 
1 - 12 of 12 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top