Beehive valve springs

JAC · #1 (**permalink**) 07-17-2009, 05:19 PM

Has anyone had any trouble with beehive valve springs breaking? I was running the engine (392 Z head Ford racing crate engine) at idle when I heard a noise so I shut it down right away. Took the valve cover off and found a broken spring on the intake valve. Valve hit piston and bent the valve. Maybe 2 hours on engine, had it for two years. Just wondering if this is a common problem, or did I get a bad batch of springs. I know I don't trust the rest of the springs, and will probably replace all of them. Beehive? Thanks.

DMXF · #2 (**permalink**) 07-17-2009, 07:29 PM

Chevy put Beehives in the Z06 vette engines from the factory and many have failed, such that I've heard pretty much all the guys that hop them up install better quality traditional style springs of the appropiate rate.

Jim Vander Wal · #3 (**permalink**) 07-17-2009, 10:01 PM

Beehives (Comp Cams) cost me a rebuild in '07. Engine/car were 2 years old and about 20k miles. Intake spring let loose and the valve broke off in the cylinder. Trashed the chamber and piston. Replaced with traditional dual springs.

The shop that did the rebuild blame the loss of two championships on beehives.

Comp Cams said that they had a supply of bad wire that may have been the cause of the failures.

Jim

RICK LAKE · #4 (**permalink**) 07-18-2009, 03:01 AM

JAC Could you fill in the story a little better. I have be running Beehives for 4 years. I also am a Chevy and GM master tech for over 25+ years. When Beehives came out in the begining there was some bottom spring breakage. In the last 10 years I have seen only 2 broken. 1 motor had 210,000 miles on it and no oil pressure to the upper end. The other is a putz with a ZO6 supercharger motor. He breaks, trannies( 3rd ) rearends (2) and the motor has been replaced (1). Rear tires replace every 3,800- 4,000 miles. He is on the 4th clutch. He is running a SPEC one. If you are running hard and banging the rev limiter you can break valve springs. I limit my motor to 6,200 rpms because of the 26120# beehive have a limit of .600" total lift. My cam is a .587"-.607" hydro roller. Motor is a 482. This is another reason for limit of rpms. If you over rev the valve train and cause float, something is going to break. You may want to look at PAC valve springs. They are a little stronger than Comps are. Was this motor just rebuilt?? Where the heads and block machined to true up the surfaces? How large is the cam shaft? 80% of motor breakage, IMO is from not matching parts for an rpm range and over extending them beyond there limits. Up to 6,500 rpms beehive work great. After this and at 7,400 rpms in an LS2 motor they are all done with controlling of the valve train. The only advantage of dual springs or with a dampener inside the main spring is if the main spring breaks there is a good chance that the dampener spring will save the valve from hitting the piston and doing major damage. The only thing that is different between beehive and normal springs is the look and how they control harmonics at high rpms. I did pick up 12 hp on a dyno with these springs at 6,000 rpms. This was more to do with valve control with a hydro camshaft. I also lost 300 rpms because of going to Erson rockers that wieght more that a stock FE rocker. I am working on a lighter valve train and other tricks to increase rpms without valve floating. Rick L.

JAC · #5 (**permalink**) 07-18-2009, 01:38 PM

New crate engine from Ford Racing-2 years old, maybe 2 hours of run time, no over reving, hyd roller .580 intake .602 exhaust. Body isn't on car yet.
Jerry

olddog · #6 (**permalink**) 07-18-2009, 08:37 PM

I know some dirt trackers that back their rockers off so that all valves are closed, during the winter storage. They swear that high lift set ups will weaken the springs when they set open for a long time and can lead to breakage. If your engine set for 2 years in one spot, that may have been a factor.

RICK LAKE · #7 (**permalink**) 07-19-2009, 03:48 AM

JAC Jerry with an FE motor a back off the rocker shafts every year at the end of the season. I don't have the comp cam spec sheet on all the valve springs but only a few are good for cam shafts over .600" lift. If you have time and can run the motor until fully warm, pull a valve cover and get a feeler gauge and check for coil bind. Comp said that .100" is min. I know guys running 1/4 mile with .060" clearance. Have not seen them break them but after the season, new springs are installed. It is possible that you do have a bad valve spring and nothing more. Have you called Ford racing and ask about this issue. This would be a good place to start. Call them and say you where breaking in the motor on a engine stand (NO DYNO CELL) and tell them what happened. If nothing else try and get the part# of there valve springs. I have a funny feeling they are cheating with a spring and a .580" max lift spec and going to over .600" and hoping the .020" is not going to cause a problem. Also was your motor a new block or recycled one? In hind sight maybe this just saved you another $7,000 + motor replacement.

Rick L.

SONICUSA · #8 (**permalink**) 09-12-2009, 08:38 PM

My speed shop- Boyd's Machine & Racing Engines- Norman Ok builds a lot of race motors... drag, short/circle track & marine. They recommended the beehive springs on my rebuilds (two BBC 468's) they have Brodix heads, roller camss, hydraulic rollers, roller rockers, etc. all met Comp's tech specs. Both engines were dyno'd at up to 6000 rpm.......This is a Marine application but.... both engines have broken springs (2 incidents)... both intake & exhaust, a total of 6 springs on 3 different heads of two different engines with less than 5 hrs on the engines. Neither engine has exceeded 4500 rpms in use.... EVER!! When Boyd's contacted Comp about this, they said they had never had an ovate (Beehive) spring break/ or fail. I found that hard to believe after reading this post!! Comp must be worried about the bad press on the Beehives. They also verified all the valve & cam specs again with Comp. We had to pull 3 heads, replace 5 valves, replace one piston, replace one valve seat (broken valve) and are replacing all the springs with duals as I used before. Beehives leave no safety factor on a spring failure!! Better to use duals...... would have saved me alot of money & frustration!!

RICK LAKE · #9 (**permalink**) 09-14-2009, 05:52 PM

SONICUSA Sonic I would like to hear a little more info on these valve spring failures. GM has been running beehives since 98 in V6 motor with only a very small failure rate. A marine motor is different that a street or 1/4 mile motor. For you to break this many springs, IMO something was not done or checked for clearance. I have run a set of #26120 BBC spring in my motor for 4 years, no failures from the springs. I have had 2 broken rocker shafts. Auto cross and roadracing.
Where are the springs broken? Top, Bottom or in the middle? What cam shaft are you running? What rocker arm ratio are you running? Has the oiling system for the heads been improved?
From what was said these boat motors where never over 4,500 rpms and dynoed at 6,000. I run a hydro roller camshaft and crane hydro lifters. The rockers are ERSONS. Push rods are hollow 5/16". I have run this motor on a chassic dyno and motor dyno. 5,800 rpms the valves float. I have pushed the motor to 6,200 rpms to see how much HP is lost in the last 400 rpms. What has saved my motor is flooded heads with the oiling filling the head to the oil drains out of the pushrod hole in the intake. The other thing is my lash is only .015" plunger depth. My motor block and heads are Aluminum. This lash is gone when the motor is hot.
If your valve spring where blue at the bottom or snapped at the bottom, they where overheated and lack of cooling killed the springs. I have hear that Comp had some bad wire, couple years ago and springs breaking from spring binding at high rpms. I have a guy behind my house running beehives and turning 7,200 rpms in an LS2 motor at 7,400 rpms the valve train goes bad fast. 2 years and 30+ races on the east coast no failures. Again a different motor but heavy abuse.
I agree about having only 1 spring for control of the valve is not the best thing but if you know the limits of these springs and have good lube to keep them cool, there should be no failures. If you are not happy with Comp beehives, you might have looked at PAC springs. They have a spring with a higher ratio, 420 instead of 377 open rate. 20 more on seat pressure.
My last question is are you running spray bars in the valve covers? I have question Comps Tech guys over the years and not been happy with their info on some issues and learned by failures. You have two 468 motor with top of the line parts. Something is not adding up with failure. Would like the specs on your motors, PLEASE. Rick L.

Mus408 · #10 (**permalink**) 09-22-2009, 07:39 AM

I'm assembling a 427 SBF stroker,and the heads came with the recommended 26120 BBC Beehive springs for hyd. roller cam use,from TEA.
My cam has a rated .600 lift on both Int. and Exh.
I got a bit nervous,when I checked the springs on the pressure checker, to see the bottom 3 coils start to stack near full lift! The actual measured install height is 1.890 with 157 psi. and 380 open psi.
I assume this is how the spring is designed to work? There is still plenty of coil clearance at the upper coils.