Welp. Someone had to be first <img border="0" title="" alt="[Sad]" src="gr_sad.gif" />

Last Friday I was coming home from the track, opened up the spray a little bit on the beltway and let her rip. At the top of 3rd gear I started getting some misfires. I let off, misfire code went away after about 30 seconds... car ran great, but a little down on power (I though I had fouled plugs... no biggie). Saturday I changed out half the plugs, and the car was running fine. I drove it about 200 miles between saturday and wednesday afternoon. Wednesday evening I was coming home from class and I started getting a massive misfire code. I limped the car home about 20 miles and got to the house. Autotap showed me as having TONS of misfires on cylinders 5 and 7, and some on 2. Tried changing plugs, wires, coil packs, etc to no avail. Thursday I got out and pulled the valve covers off and found 2 broken springs. One on the #1 intake valve, and one on the #5 exhaust valve.

Here are some pics. This is the #5 exhaust valve spring broken into 3 seperate peices.
http://www.cepheid.org/~kris/photos/...s/P1010002.jpg
http://www.cepheid.org/~kris/photos/...1010002-sm.jpg (small version)

And this is the #1 intake valve spring pulled off the head. It broke at the very top and was still holding very good spring pressure... but I'm sure it wasn't good.
http://www.cepheid.org/~kris/photos/...s/P1010003.jpg
http://www.cepheid.org/~kris/photos/...1010003-sm.jpg (small version)

I went ahead and ordered another set of REV-1116 Springs from thunderracing because they were able to get them to me next day (I really love their service) They got here today, I might try changing out the springs this weekend, but I am waiting on a new spring compressor from MORE Performance. I did not install my valve seals correctly the first time around, so when the new compressor gets here I will be pulling off every spring and inspecting it off the car. I will also be taking one of the unbroken springs that is currently on the car (as well as a brand new, never used one), and taking them to my cylinder head guy to check out and see if there's any further degredation in the spring to see if this is a couple of bad springs in the batch, or if they're all a ticking time bomb.

Overall, even though a couple of springs broke, I'm still happy with my purchase of these springs. Had this been a comp 918 (which when I bought these was right in the middle of their "BAD" batch), I'd probably be shopping for a shortblock instead of a couple of replacement springs.

My setup consists of a Comp Cams 224/224 .581/.581 112LSA cam, these springs with the A&A Corvette Specialties spring seat/retainers setup (to get the installed height back up to the correct spec)
I put 2600 miles on this setup before the spring broke, about 10 passes at the track. And yes, I did heat cycle them when I installed them (3 times in fact).

I guess I'm to chalk this one up to manufacturer defect. I'm sure I will be shipping these springs off to either Andy @ A&A or to REV for them to analyze and see what's up.

Kris

 

about how many RPM were u turning when they let go

 

I was towards the top of 3rd... I'd say probably around 6100-6200. I got a SES light and I immediately pushed in on the clutch and let the motor wind down to idle rpm. The SES light started flashing (misfire) I just coasted with the clutch pushed in for about 30 seconds and the SES light stopped flashing and went off. Car continued to drive perfectly after that (though I didn't get on the nitrous anymore since then)

<small>[ November 15, 2002, 03:02 PM: Message edited by: xaon ]</small>

 

xaon, damn sorry to hear about this. Do you think it had anything to do with not installing the seals/seats properly that you mentioned? I hope you get it all fixed up real soon <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />

 

The seats were installed properly. Just the seals weren't. I don't think they had anything to do with causing the breakage either... they just caused me to burn a good amount of oil. (about a quart every 500 miles or so, and turned a brand new set of TR6 plugs BLACK in 4 days.

 

Ok, yeah, valve seals would have nothing to do with that breakage. Thank god for that inner spring, eh?

 

Did u just drop them in or actually check installed heights for each intake/exhaust?

There supposed to setup at 1.84@135..

JS

 

When I pulled off the #1 intake spring yesterday (a broken one), i put the retainer on the valve with the keepers and while pulling up on the retainer (level), I used a small ruler to measure the space in between the retainer and spring seat. I came up with between 1-13/16" and 1-7/8", (1.8125 and 1.875) so the installed height appears to be the correct ~1.84" I see no variations in the height of the retainers on any of the other valves, so I can only assume they are all at proper installed height as well.

 

These are the double valvesprings right?? dang man.... <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" /> <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" /> <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" />

 

But u only check one spring?U cant do this and expect all the others to fall in line.Sorry about ther bad luck but it looks like u didnt take your time and that can cost u sometimes..

JS

 

I didn't check any at first. But what I have done is checked the installed height where a BROKEN spring came from. It seems as though to me if the broken spring was at the correct installed height... then it really shouldn't make a difference whether I checked the non-broken ones or not. I could go through and check every one right now if I wanted to, but I can tell by looking at them that they're all at the same height. And even moreso would be noticeable when I laid a straight rod across all 8 springs on that side. So improper installed height isn't the problem, being as I broke a spring that WAS at proper installed height.

 

Installed height would also only be a problem if I were running into coil bind. Which I am not. With the cam lobe in the "up" position and the valve pushed down as far as the cam will push it (I really don't know the technical term for it). I have over .10" clearance between the coils. My head machinist stated he generally looks for a minimum of .090" between the coils in this position for a motor with hydraulic lifters.

 

Not always...
If your spring psi were too light or too tight u could weaken the spring/fatigue it and thats why the broke.

JS

 

You might think about replacing the rockers arms on the broken springs. The needle bearings can get damaged by blunt force of failure by the spring. Glad the block didn't get damaged.

 

Sorry to hear about your rotten luck Kris. My springs are coming up on 2500 miles with over a dozen passes using a Comp 220º .581" cam. I guess we'll find out soon if this is an isolated problem or more wide spread. On a lighter note, I'm relieved to see that the inner spring limited the potential damage. Limping a car twenty miles couldn't happen with a single spring in play. I will also agree with strokedls1 that it would be wise to replace the rockers associated with the broken springs. It seems that a number of engines with broken springs suffer rocker arm failure soon after.
I would suggest sending all the springs to Al @ REV for inspection. If you need a replacment retainer or base send me an email. Thanks for the update.

Richard <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

 

Thanks guys. It's definately a little bit of a bummer, but it definately could have been MUCH worse.

I do plan on getting some more rocker arms and replacing them. I talked with Andy @ A&A yesterday and it seems as though this is probably an isolated incident. I'm going to send all the springs over to him and get a new set after I get them all swapped out, and I'm sure he'll send them to REV for inspection from there.

Richard, I don't think I damaged any spring seats or retainers. But If I did, I'll definately shoot you an email. These peices are top notch.

 

Dang, I have 2500 miles on mine now, but I haven't done any track runs yet. <img border="0" title="" alt="[Sad]" src="gr_sad.gif" />

Well, on the bright side, sounds like the inner spring did it's job and you didn't end up with too much damage.

Chuck

 

I am just at 4000 miles on my set and although no track run, I have had several street runs to the rev limiter. I just had a high mph run against a mustang to 135+ red lining all the way with no problems.

LunaticTA and I are just now waiting on LS1Edit to get here, most likely we will pull the covers off and make sure that everything is still seated and torqued down to specs.

We only have the 224/.561/112lsa so we would not be putting as much on the springs.

Good luck and let us know what REV says they think could have happened.

 

UPDATE: Got the two broken springs replaced today. No more excessive misfires. Going to replace the rest of the springs this weekend with the new batch along with some new valve seals, then I'll ship them all back to Andy @ A&A for a new set.

Some Pictures:

http://www.cepheid.org/~kris/photos/...1010006-sm.jpg
http://www.cepheid.org/~kris/photos/...1010007-sm.jpg
http://www.cepheid.org/~kris/photos/...1010008-sm.jpg