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451 Road Runner woes

hunt2elk

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Noticed a more pronounced ticking sound coming from the motor the last couple of times I've had the car out. Figured the valve lash needed adjusting since there is now 480 miles on the new build. Check out the good stuff I found when pulling off the valve cover. #3 intake rocker is broke and pieces of metal are abundant. What the he!! would cause this? Time to regroup and get a plan to move forward. Its times like this that I am about ready to sell both my jalopies and buy a newer Challenger :angryfire:.

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What brand of rockers are those, are they needle bearing and how many miles are on them. I've read with Mopars running needle bearing rockers isn't necessarily a good thing, for one the rockers are directly fed oil meaning little to no gain and the bearings thin the rockers making them weaker.

Without knowing more I'm thinking weak rocker vs stout spring! When building mine rockers where my biggest concern, like you mentioned "metal abundent". I went with Comp Cams Magnum rockers, they're stainless with bushings on the shaft and needle tips. Let us know what you find.
 
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those don't look like heavy springs. coil bind possible. most people don't check lift at the valve and all adjustable rockers that i've played with have a higher than advertised ratio. it's probably a flaw in the rocker. are those proforms?
 
those don't look like heavy springs. coil bind possible. most people don't check lift at the valve and all adjustable rockers that i've played with have a higher than advertised ratio. it's probably a flaw in the rocker. are those proforms?

That's what I was thinking they looked like, I had a set that I test fitted on my motor and the valve contact was way off.
 
Isn't the Proforms the ones that are not recommended on Mopars? I've used the 'old' 1604 Isky's for years and turned one engine 7300 and 660 lift with them. They are ductile iron rockers and non needle bearing. What's out there these days that is similar to them?
 
The rockers are Mopar Performance and the springs are Comp that came with the cam.
 
A quick look at the rocker bushing will tell you if there was a lack of oil. Did you use the old push rods or use a push rod length checking tool? The adjuster looks like it's way to far up into the rocker arm. The cups need to be able to get oil from the hole in the rocker arm. The push rod end appears to be discolored.The springs appear to be single wound with a damper but if that came as a kit , I'm guessing the springs are a match to the cam. Did you check the spring height or use valve seat spacers? Did you check for coil bind?
 
A quick look at the rocker bushing will tell you if there was a lack of oil. Did you use the old push rods or use a push rod length checking tool? The adjuster looks like it's way to far up into the rocker arm. The cups need to be able to get oil from the hole in the rocker arm. The push rod end appears to be discolored.The springs appear to be single wound with a damper but if that came as a kit , I'm guessing the springs are a match to the cam. Did you check the spring height or use valve seat spacers? Did you check for coil bind?

I really don't know much about engines and had a shop put everything together. I do remember him saying that he ordered the pushrods after measuring with a tool. You are correct that the pushrod ends are discolored and so are the bad rockers. I am going to try to get time to pull the motor this weekend and think I may take it to another builder. The shop that put the first one together used to be awesome, but I think they have gotten to big and don't spend as much time as they used to making sure things are perfect. If the Mopar rockers aren't the greatest, what would be a better alternative?
 
I'm sure those push rods are the wrong length and that's what started the whole thing. If your car is mostly a street car with a mild cam, there are lots of rockers that will work just fine. Just stay away from the bargain basement stuff. Try to get ones that are made in the USA and not China. There are guys that have run Mopar Performance rockers for years and years. All you really need is the correct valve geometry. As for rockers, it depends on how much you want to spend. Be careful of the terminology. There are roller tip rockers with a bushing in the rocker and there are ones with rollers in the rocker itself. That's when the prices go up. I've used Harland Sharp rockers in all my race cars.
 
After talking to Dave Hughes at Hughes Engines I went with his company's rockers and valve train.
 
the cup color and location to the oil spurt hole look good to me. those adjusters have the newer extended ball and i wouldn't and don't use the ancient "2-3" threads showing thing because that refers to an adjuster that hasn't been made in over a decade. i think it's simple rocker fatigue and alum is good at doing that. comp 911 springs are pretty stout for a single spring/dampner, close to 400inlbs rate, and i don't use them anymore.
 
After calming down a bit and looking at things closer, it looks like both cylinder #3 and #5 were having issues. Both those cylinder rockers and rods are discolored. The other 6 look normal. Sure wish I knew if this problem was caused by the shop that put the motor together. I am having a hard time deciding if I should take it back to him to see if he will make right, or go elsewhere.

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Perhaps it's time to see what's going on down at the cam - mainly the lifters. Rod length checkers are a must and you'll need to know what spring pressure ( closed and fully open valves ) is right for the cam/lifter combination. Hope there was no damage to the engine from floating metal debris. "Bottoming out" caused by rods too long or bitched lifters can cause failure of the rockers weather steel ( OE ) or aluminum. That's quite a scorch mark on the rockers, almost as if combustion was blowing right past the guides and seals.
 
I'd pull the shafts so you can inspect them, make sure everything was installed correctly. Then I'd run the oil pump (with a drill) while turning the motor to make sure your getting plenty of oil upstairs. Might want to change the oil first!
 
the new pictures do show heat from lack of oil. are there any restrictors in the heads?
 
The push rods are too long. Look at the threads exposed on top of the adjusters. Look at picture #3, 3 intake & exhaust and 5 exhaust are discolored. The cups are up too high for the rocker oiling holes.
I'm not very impressed with your engine builder.
 
It may be wrong but I have always heard a thread to a thread and a half sticking out the bottom of the rocker was correct. If that's the case it does look like the pushrods are to long as your adjuster are all the way up inside the rocker.
Best of luck and maybe its not too bad.
Matt
 
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