Being an owner of a set of these and knowing the limits on lift always sat out there I noticed the new versions allow for a bigger lift because they went to LS Beehive springs. It also allows for 6800 rpm .. not to shabby. Direct fit on heads 2010 to present.

I made my own kit , using PAC 1518 beehives which allow for 650 lift. seats , retainers and locks. Now anyone with these heads is not stuck with the hot cam lift of 525/525 ..

Just thought I would share the info for anyone interested or even anyone on google looking to improve these heads.

 

It looks like what they've done with the ZZ5 crate engine using the beehive springs but sticking with a mild cam.

 

True , and they are a good set of heads , i know the AFR fans will argue different but over all my little 350 screams with them.

 

Didn't you build a ZZ430 clone? Those ZZ4 short blocks are pretty good deals.

 

in another post i pointed out that i and many other people do not like beehive springs because of oscillation. i was told comp cams had "solved" that problem, which i doubt. however comp has apparently come out with a conical spring to , wait for it, combat oscillation. I'm not sure to what degree this application would be affected but it may be wise to investigate . a broken spring can cause real damage. people seem to think they can just bolt a set of heads on, im not saying thats an issue here. however you should always check even the best stuff or have some qualified person check them. trust but verify.

 

Yes I did build the ZZ430 clone .. I never liked the fact max lift on the valve springs was so close to the hot cams total lift so I have always been interested in different springs.

7t9l82 ( Cool name )

I did read that , I talked to Pac and i read this as well before I talked to them. Comp changed manufactures from PAC to I do not know who some suggest china .. In any event PAC was clear that the beehive will hold the 6800 all day and night as GM states and I opted for the Nitrated set which is a lot more expensive as it is a lot more durable.

I will never see 650 lit on these heads , I may see 575 or 600 next season and if they break I will be mad but have read and talked to several people and at this point in time am confident the 1518 is going to serve me well.

Is comps issues inherent to beehive design ? I also read that the design was suggested in the 1920's by some wiz bang dude but because metallurgy was not what it is today his beehive theory was just that until today's modern era. Something to do with resonance and different coil sizes do it at different times and make the spring more stable at high rpm ...

Now this is all regurgitated from the dozens of searches I have done so do not quote me LOL ..

 

my belief is that is an inherently flawed design, however my thought is that better quality wire may make it workable in some applications.good luck, you have a nice project there.

 

Valve float was analyzed and found to be caused largely by resonance in valve springs that generated oscillating compression waves among coils, much like a Slinky. High speed photography showed that at specific resonant speeds, valve springs were no longer making contact at one or both ends, leaving the valve floating[11] before crashing into the cam on closure.

For this reason, today as many as three concentric valve springs are sometimes nested inside one other; not for more force (the inner ones having no significant spring constant), but to act as snubbers to reduce oscillations in the outer spring.

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Valve springs that do not resonate are progressive, wound with varying pitch or varying diameter called beehive springs ,from their shape. The number of active coils in these springs varies during the stroke, the more closely wound coils being on the static end, becoming inactive as the spring compresses or as in the beehive spring, where the small diameter coils at the top are stiffer. Both mechanisms reduce resonance because spring force and its moving mass vary with stroke.

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That is the concern you talk about. It is very real. I was told and I was reading that the comp beehive springs where manufactured off shore and with less then desirable material and they had breakage , they claim it was limited to certain batches but instead of going back to pac for the springs they now offer the springs you are talking about.

I sure hope mine do not break

 

Broke a spring this past fall, glad that I was going to crate the original engine anyway. Once the weather up here warms up will pull the engine, pull the heads (Dart ported IE 200's) send them off to the machinist and go from there.

 

what spring was it , who was the maker

 

Its been 12 yrs but I think they were Crane, the engine spun freely and quickly up through 7200 rpm (383 designed by former NASCAR engine builder and The WidowMaker's engine builder - 1/4 dragboat). We designed the engine to run low 11's. After a lot of passes and 35k a spring broke.

 

I never liked the fact max lift on the valve springs was so close to the hot cams total lift so I have always been interested in different springs.

Well i cant make sense of the new beehive specs either. They claim 0.550" max lift but at 1.250" closed would mean no safety margin. I think their 1.250" closed number is not at coil bind but cant confirm that. I had to look in the LS section for LS6 springs specs as they put the new beehive in the specs for the old LT4 "hot cam" spring under the small block section of the GMPP catalog.

If i use a usual 1.780" installed height and 0.060" safety margin i only get 0.470" for max lift - no to hot.

Anyone have the real deal on the GMPP beehive spring #12625033?
cardo0

 

The Chevrolet Performance LS6 Beehive springs are the way to go for hydraulic flat tappet or mild roller. The install height is 1.800, Max lift is .570. Coil bind is 1.085. This is .140 safety margin. They have a #375 rate. Closed pressure is #90 but they are able to run the LS6 hydraulic roller to 6500 RPM redline with them and if your running a shorter cam you could install them @ 1.775 for a #100 seat pressure and 545 lift. Best part! They run about $60 a set New GM part #12499224
https://sdparts.com/details/gm-perfo...parts/12499224

 

Most builders I've talked with say you should run a spring that's as close to bind as you can safely run. They claim dyno proof that springs with a good bit of room between coils at full compression go into float sooner than those that are close to spring bind. There's no reason to add a fudge factor or have "margin for error", a spring with enough clearance between coils isn't going to grow shut into spring bind.

 

A few years back I ran the beehive springs with 10* locks in my 1996 LT1 with a Comp Cam, specs on it with 1.6 rockers lift on the intake: 0.536 - and the exhaust 0.544, 108 LSA and ran them up to 6800 many times (1/4 mile at a time ) without any issues. I'm not saying you are wrong, just offering my personal experience.

 

My under standing is the GM ones are good to 550 lift and 6800 rpm , one nice thing with the fast burn heads is the valves are light as a feather and they will rev like mad.

 

Seems to me the application is also a huge factor.

The beehive springs seem to really smooth out the entire valvetrain, but are really working hard.

I read somewhere that Comp has actually hardened the coils differently to allow them to soak up that oscillation and vibration.

Cool trick if they did it. I believe a set of these may be going into my car after this summer.

This is an interesting video from Comp comparing their beehive springs to regular springs.

 

That video is good , what they show is resonance that results in the float and rotation. IF they added a dampener or an inner spring to that first test that issue would instantly go away . Beehive because the coils are different diameters cancel out resonance like a dual spring would.

It is an old , old idea and comp cheeped out and had a lot of there springs break GM had some 2.. Thats why I went to PAC and got the better beehives.

 

The specs on the LS6 beehive say 1.800 install height, .570 Maximum lift. 1.085 coil bind. This leaves .140. This is not a margin for error or fudge factor. This is the amount GM engineering determined you need to leave to use these springs. The design is different than a conventional spring, different engineering "rules" apply with a spring that varies in construction from one end to the other which is the main reason they offer better valvetrain control with lower closed and open pressures to higher rpm. running springs close to coil bind will reduce harmonics but it does it by absorbing them because the spring "bounces" like a slinky and they physically can't do that at coil bind. They also will have a greatly reduced life expectancy and will lose pressure faster due to fatigue. Here is a high speed film of spring surge. It will clearly show why running close to coil bind is a real bad idea, why spring manufacturers don't recommend it, why specific spring recommendations should be followed if using conventional springs and the factory don't do it. What works on the racetrack to gain a little higher redline does not always correlate to the street and long term durability.

http://www.engr.colostate.edu/~dga/h...pm_1000fps.wmv

http://www.engr.colostate.edu/~dga/h...pm_1000fps.wmv

 

I think that you might be overlooking something. Just because you can buy higher lift springs doesn't mean that you can use a cam or rocker arm ratios to achive higher lift.

At some point the valve stem isn't physically long enough or the heads can not be machined for deeper spring pockets. If you look at race type heads they come with .100 longer valve stems or even .200 longer like I use in my 434 with .714 valve lift. My installed spring height is 2.00 inches.

I came across this. Heads flow from your fastburn heads.

Intake Fast Burn
.100"........ 65
.200"........ 133
.300"....... 183
.400"........ 225
.500"........ 254
.600"........ 244
.700"........ 248

Exhaust Fast Burn
.100"........ N/A
.200"........ 98
.300"....... 129
.400"........ 150
.500"........ 171
.600"........ 179
.700"........ 184