Had the car out the other and it was running great. After a 20 minute drive, we stopped for 15 minutes or so and then pulling out onto the road, I noticed a loud ticking noise that followed the speed of the motor. Higher r's, faster tick. It idled a little rough so I babied it home about 2 miles, staying below 1500 rpm's. After pulling the valve cover, I found a broken exhaust spring on cyl 2.

I pulled the rockers on both exhaust and intake- valves are sitting high and don't look bent and the push rod is still straight. It's looking like I got lucky and only have a broken spring, no other damage. I was planning to pull the exhaust and intake spring, have my speed shop measure the spring and then get a comparable replacement. The motor has <5k miles on it and I don't drive it hard at all, no drag racing, etc. It's really a weekend toy that gets driven once per month or so. Based on the low mileage and minimal usage, I was planning to replace only the 1 spring. What are the risks in this vs. swapping all 16 springs? Also, is there anything critical in the cam specs I need to swap the springs and remove/replace rockers? I had one shop suggest tearing the motor down, pulling the cam and getting a serial number to find specs about it. For simply swapping springs, I couldn't see going through this trouble. What do you guys think?

I'm running a 383 stroker with an auto tranny. Unfortunately, I don't have any specs on the motor or cam- it was built by a guy 3 owners back from me. I talked to the prior owner and the one before him and neither have any specs or contact info for the builder.

Here's a close up of the damage:

 

Better to replace them all.

If it has a good size cam in it try and turn the motor over or at least drive it once a week so the springs arent sitting there compressed all the time they will live longer.

 

spring bind causes valve springs to break, check your clearances, if the spring even come close to binding it will bottom out at higher temps and rpms. looks like someone didnt do there homework.
Looking at the pic again, that valve is not running at center of roller, even when compressed the roller should stay close to center, better check things like valve bent or stud bent or even wrong push rods or springs.

 

3 owners back? Get a set of springs.

 

Consider yourself lucky..I blew my motor last year from dropping a valve.... COMP 918's now ...good for th elift I am pushing. Dual patriots are the way to go, I hear, if right for your application.

 

You can take one of the other springs and have pressure measured to get an idea of what you need. Is it a flat tappet cam or a roller?

Need to measure installed height and ck for binding at full lift, valve seal etc.

Maybe it's just the pic...but is that adjuster lock screw a lot higher than the others? Why? Should be about the same down the line.

JIM