LT1-LT4 Modifications 1993-97 Gen II Small Block V8

broke a valve spring last night.

Old 08-26-2012, 07:20 PM
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Default broke a valve spring last night.

I broke a valve spring last night while driving home. I got on it a little hard but nothing crazy a few minutes later the car felt like it was miss firing. I shut it down but fired it back up. I didn't hear anything that sound like it was making contact but I shut it back down. got my truck and trailer and towed it home. I pulled the valve cover on the driver side and the very bottom coil on the spring broke off.

I am going to hook the compressor to the cylinder to see if it hold pressure tomorrow. The thing is every thing is well with in specs with the cam and rocker so I am not sure why the spring broke. I am going to pull two other springs and bring them to the machine shop and have them tested to see if any of the other ones are warn out. Every one seems to think it was just a freak thing as the springs only have about 15k on them.
Old 08-26-2012, 07:41 PM
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What kind of springs are they?
Old 08-26-2012, 07:53 PM
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Originally Posted by guppymech
What kind of springs are they?
X2 Gotta know
Old 08-26-2012, 08:22 PM
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Originally Posted by twofast4lv
x2 gotta know
x3
Old 08-26-2012, 08:29 PM
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Might be a Comp 918 beehive.
Old 08-26-2012, 09:30 PM
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They could be worn out at 15k depending on the camshaft.
Old 08-26-2012, 11:22 PM
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Originally Posted by fergymoto
They could be worn out at 15k depending on the camshaft.
Some of thise new profiles are brutal. Had a guy that lost a set of springs in the first 500 miles. LSR lobes If I remember right with PAC springs

I won't use bee hives. Snap a spring and loose an engine? No thanks!
Old 08-26-2012, 11:40 PM
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howards 98215 with a cc502 and 1.6 rockers. These were recommended by XXXX. 96capricemgr and RamAir95TA had concerns with how they were installed because X told me to install them with out the dampeners. I questioned a few others about the setup back before I installed it which was 2 years ago and every one had good things to stay about the springs on another forum. This is a really weak spot for me so I asked X and took it at face value because of his name in the industry I hope this wasn't a mistake on my part.

I do want to add they were checked and installed at the right height.

I have a brand new set in the box I was going to have installed on the 94 lt1 going into my 69 corvette so I am going to run down to the machine shop and bring two springs with me to compare to that set. If they turn out to be weak then ill have to pick a new set of springs.


98215 Single with Damper 1.265 .875 NA NA Y 115 @ 1.800 380 @ 1.200 430 .640 1.100. specs from howards web page. that is .640 of max lift and 1.100 coil bind

Last edited by Adam1203; 01-17-2014 at 10:40 PM. Reason: Edited to be polite.
Old 08-27-2012, 11:15 AM
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Wouldnt say there was anything wrong with the springs... "Only" 15k ain't bad for a 100 dollar set of springs on an aftermarket cam. Harmonics will kill a spring much faster if removing the damper was truly an issue.
Old 08-27-2012, 02:15 PM
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Originally Posted by TwoFast4Lv
Some of thise new profiles are brutal. Had a guy that lost a set of springs in the first 500 miles. LSR lobes If I remember right with PAC springs

I won't use bee hives. Snap a spring and loose an engine? No thanks!
Duals FTW. My cam is a spring eater though, so I am only expecting to get around 5k miles out of a set. That's about a years worth since its not a DD though, so no biggie.

I would not run $100 springs with no damper on an aftermarket cam. I'm surprised it lasted 15k to be honest.
Old 08-27-2012, 02:24 PM
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Beehives ftw! went though the traps last night at 7550 Dirt track solid flat tappets are going 8200 all season on them. i did lose a spring (wire flaw) last year with only 15 min run time, i don't know if duals would have saved it at 3500rpm cruise, valve would have floated bad and smacked the piston anyway.
Old 08-27-2012, 02:46 PM
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Originally Posted by Adam1203
I am going to pull two other springs and bring them to the machine shop and have them tested to see if any of the other ones are warn out.
I would change the whole set no matter how they test for pressure. A dfect in the wire most likely won't show up.
Old 08-27-2012, 02:47 PM
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Originally Posted by TwoFast4Lv
Some of thise new profiles are brutal. Had a guy that lost a set of springs in the first 500 miles. LSR lobes If I remember right with PAC springs

I won't use bee hives. Snap a spring and loose an engine? No thanks!
I broke a beehive last year and there was no engine damage. It's more of luck when the spring break happens. If you snap a spring at 6k a tiney inner spring isn't going to save the motor.
Old 08-27-2012, 04:35 PM
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What'd you put back in it speeddemon?
Old 08-27-2012, 05:32 PM
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Yah I don't. I figured the CC502 being a mild cam it wouldn't be a big deal. Its pretty much on par with a hotcam. I didn't focus on the cost but more on the specs. I figured they were well with in range and being a mild cam it would be okay. guess I was wrong.

what do you guys recommend for springs for this cam? I don't want to be going through this every 15-20k.
Old 08-27-2012, 06:11 PM
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You could go with whatever spring Comp recommends to use with the CC502, which is probably a beehive. The Crane 10308 is a popular dual spring assy.

Last edited by guppymech; 08-27-2012 at 10:15 PM. Reason: add more spring info
Old 08-27-2012, 06:50 PM
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Originally Posted by speed_demon24
I broke a beehive last year and there was no engine damage. It's more of luck when the spring break happens. If you snap a spring at 6k a tiney inner spring isn't going to save the motor.
I disagree. The inner spring will keep the retainer on and keep the valve from dropping.

We have had two engines in lately with behives that sucked the whole valve.

We have had about a dozen with duel and tripples come in with a miss and find broken springs. One had bent valve(not enough spring for overly agressive lobes) but other then that it was a spring change and scope the cylinder and send it back to the track

This is just my experiance from working on them every day
Old 08-27-2012, 07:03 PM
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Originally Posted by speed_demon24
I broke a beehive last year and there was no engine damage. It's more of luck when the spring break happens. If you snap a spring at 6k a tiney inner spring isn't going to save the motor.
Don't mix up a proper dual spring with a single spring w/ damper .
Old 08-27-2012, 07:26 PM
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Can you post a pic of the broken spring?
Old 08-27-2012, 08:53 PM
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got it apart and the cylinder appears to be fine.


Originally Posted by Speedy
Can you post a pic of the broken spring?
Sure. unfortunately I did not take pictures of it on the car. the smaller piece was on the bottom.



and this was how it was siting in the car


Last edited by Adam1203; 08-27-2012 at 09:05 PM.

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