Be prepared to lose sleep over Beehive 918's !!!!
04-11-2007 | 03:53 PM
#21
I noticed all of yours broke at the first coil at the top of the beehive. I had a blue stripe 918 break at the first coil several years ago, but it was at the bottom. The engine was running fine and I didn't even know about it until I pulled the heads off to ship them to Richard at West Coast Racing Cylinder Heads to have them CNCed. As I was pulling the valves out and removing the springs the first coil on one of them stuck to the deck of the head. The spring had not rotated even though it was broken. No telling how long it would have run like that. I've had them on there for many thousands of miles now and I might have a broken one on there right now, but you couldn't tell it by the way the engine runs. I have a set of those Manley green stripes w/titanium retainer I'm going to switch over to in the near future. If any of the 918s are broken I'll post it, but I have my doubts.
04-11-2007 | 05:24 PM
#22
I personally like the 918s because they retain the beehive shape and reduce mass at the top of the spring, which moves the most. They are like a factory spring on steroids. There is a reason that GM spent so much time and money in designing (or whoever designed them for the ls1's back in the mid 90s) the beehive spring. I'm a firm beleiver in the 'hype' surrounding the harmonic stability associated with the shape and style of the spring. Add into the equation the use of a smaller and lighter retainer, and you have a more stable valvetrain.
I'd consider running a higher lift cam when/if comp comes out with a spring that is stable for the higher lifts than the current 918.
I'd consider running a higher lift cam when/if comp comes out with a spring that is stable for the higher lifts than the current 918.
06-27-2007 | 01:20 PM
#23
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From: Hartsdale, NY
I did not believe anyone challenged the supieror design of behive springs.
The problem is not with the design but with the manufacturor and their lack of service and desire to incur costs to recall a defective product that has wrecked many motors over the years.
The problem is not with the design but with the manufacturor and their lack of service and desire to incur costs to recall a defective product that has wrecked many motors over the years.
06-27-2007 | 01:50 PM
#24
Launching!
Joined: Jun 2007
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From: NC
Originally Posted by The Alchemist
I'd consider running a higher lift cam when/if comp comes out with a spring that is stable for the higher lifts than the current 918.
06-27-2007 | 02:18 PM
#25
Originally Posted by Yeahdoug
That springs exists. Part number is PAC-1518.
And just at first glance I can see a couple differences on them compared to the 918's made by comps new supplier, the top coil doesn't have as steep as a pitch on your springs which is where I'm guessing the problem lies on the 918's? Also it looks like the top coil gets alot thinner quicker too on the 918's and this combined with the steeper pitch on the 918's creates a higher stress point on the top coil, or I could be way off. Last edited by speed_demon24; 06-27-2007 at 02:25 PM.
06-27-2007 | 02:47 PM
#26
Launching!
Joined: Jun 2007
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From: NC
Originally Posted by speed_demon24
Yep and mine came in today. And just at first glance I can see a couple differences on them compared to the 918's made by comps new supplier, the top coil doesn't have as steep as a pitch on your springs which is where I'm guessing the problem lies on the 918's? Also it looks like the top coil gets alot thinner quicker too on the 918's and this combined with the steeper pitch on the 918's creates a higher stress point on the top coil, or I could be way off.
And just at first glance I can see a couple differences on them compared to the 918's made by comps new supplier, the top coil doesn't have as steep as a pitch on your springs which is where I'm guessing the problem lies on the 918's? Also it looks like the top coil gets alot thinner quicker too on the 918's and this combined with the steeper pitch on the 918's creates a higher stress point on the top coil, or I could be way off.
06-27-2007 | 02:51 PM
#27
Originally Posted by Yeahdoug
Interesting. You're not way off
06-28-2007 | 08:42 PM
#29
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Joined: Jul 2005
Posts: 861
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From: Midland
Originally Posted by Matt @ SDPC
I've been talking to our rep at Comp Cams and just want to post to assure everyone that your 918 springs are fine to be installed! They called the original posted over there (they had his phone number and had already spoke with him and figured out the issue with him getting an old spring that was bad from a year or so ago).
You can tell by the retraction of the original thread and the tone of the new thread that he should not have been posting like that. There have been no more "bad batches" sent out from Comp and everyone can install them without worries! And just to put this into perspective....About 7500 of these springs are installed each month! If it was a widespread problem, CompCams would be on the phone with every distributor recalling these springs, paying to have them pulled off engines, and helping with labor to have them replaced!
Now onto bigger and better things: I'll go ahead and drop a teaser in here
Comp will be releasing the new "918 High Lift" valve spring in about a month from now! It will still be a single beehive spring which will accept the same retainers we've been using on the 918's, no machining of the spring pockets will be needed, etc. It will be built to handle .650" lift! Again, just a teaser...MORE LATER!
You can tell by the retraction of the original thread and the tone of the new thread that he should not have been posting like that. There have been no more "bad batches" sent out from Comp and everyone can install them without worries! And just to put this into perspective....About 7500 of these springs are installed each month! If it was a widespread problem, CompCams would be on the phone with every distributor recalling these springs, paying to have them pulled off engines, and helping with labor to have them replaced!
Now onto bigger and better things: I'll go ahead and drop a teaser in here
Comp will be releasing the new "918 High Lift" valve spring in about a month from now! It will still be a single beehive spring which will accept the same retainers we've been using on the 918's, no machining of the spring pockets will be needed, etc. It will be built to handle .650" lift! Again, just a teaser...MORE LATER!
06-30-2007 | 11:26 PM
#30
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From: Midland
Originally Posted by JS
I'm ordering a set of 1518's today
I already have the Comp 772's sitting here
I already have the Comp 772's sitting here
07-01-2007 | 12:54 AM
#31
Originally Posted by 91Z28
What is the max rated lift on the PAC 1518s? I have 918s installed on a set of heads right now and am wondering if I could install 1518s using the same seats, retainers, locks and seals.
07-05-2007 | 03:08 AM
#32
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From: Energy Vortex's
***UPDATE***
Well i finally got time to swap out my crap 918's to PAC 1518's . Well
the second i pulled my valve covers i noticed the spring pictured below
My batch number was 49826 and i purchased these
918's in october 06' . Here is another victim to add to
the list of broken Comp Cams 918 beehives
Well i finally got time to swap out my crap 918's to PAC 1518's . Well
the second i pulled my valve covers i noticed the spring pictured below
My batch number was 49826 and i purchased these
918's in october 06' . Here is another victim to add to
the list of broken Comp Cams 918 beehives
