Started another thread about this a couple of weeks ago after removing one intake rocker and finding chipping on the valve tip. Turns out the builder used the wrong pushrods and the roller tip was too far forward on the valve and caused the cracking, at least that is what we thought...

Fast-forward to last night when I pulled the remainder of the rockers and found much more serious damage on all of the exhaust valves. What could be causing this kind of damage? Heat, improper pre-load, poor lubrication, crap valves? Surprisingly the roller tips are still in mint condition. Hard to believe this was caused by bad geometry alone.... Any thoughts??

 

Damn. Makes me kind of leary to pull my valve covers.

Fortunately you didn't drop a valve.

 

That is nasty, never seen that much damage withoout dropping a vale. What are the specs pn the engine ? Do you have the correct springs to match the cam ?

Looks to me like really cheap valves and you are going to have to replace all of them. Make sure you use valve stem caps on the new valves and check the geometry of the valve train real good.

 

Bad material......ask the builder where the valves were sourced.

Jebby

 

The lifter preload had to be to low and the rocker tip was slapping the valve tip. Roller rocker tips or even stamped rocker tips only slide over the valve tip - they don't normally roll at all or much at all. Sorry but sliding action will not chip metal off the valve tip.

Now if the rocker tip completely slid off the valve tip and back on again that could explain it also.

My sympathies here but in my opinion someone who assembled an engine/valve train like that is not an engine builder but a wannabe engine assembler. Someone got awful lazy leaving you an engine like that or else they are incompetent building engines.

Pull the heads, replace the valves, springs, rockers, p-rods and have the valve guides checked. I'm guessing the valve guides are trashed.

Again my sympathies here.

 

I am far from an expert but seriously doubt incorrect valve train geometry caused that much carnage of the valve tips. That certainly looks like inferior material on the valves.

 

Weren't these ProComp heads?

Valve quality is highly suspect.

You get what you pay for!

 

WOW....that looks nasty, I've seen some chipping, but never seen carnage like that before...except on blowed up engines

 

I'd check ovet at Grumpy's web site . Sure looks like wrong springs and or lifters allowed slapping. Make me want to use lssh caps with new cam...

 

Yeah, pretty crazy damage. No clue if the springs match the cam specs. Honestly, when you buy a crate engine, how do you verify internals? I wasn't about to tear into a brand new motor. Quite sure i'm at the beginning of the 'you get what you pay for' nightmare journey......

Thx cardo0, I'm going to shortcut my path to sanity and just buy the AFR195's and ditch the ProComps. I won't call out the builders name here, but instead just que up my reply to the previous post. Get what ya pay for. Pretty sure you are right about the rollers slapping the valve tips and causing all this damage. Exhaust valves probably just look worse because of the cheap materials and therefore poor heat cycling and pressure resistance.....

My guess? Pot metal... that's seriously what the maimed valve tips looked like.

L88, you are absolutely correct, I got what I paid for, a ~$4k for a 420HP crate motor made of questionable components. I bought this motor not because it was exactly what I wanted, but because I could afford it while at the same time doing a frame-off. Some components were nice, but cost savings obviously came in inappropriate ways. The upside of all of this? I'm looking forward to sourcing my own stuff and doing as much of the next engine build as possible with the limited engine skills and reasonably affordable tools I can find. That's what I love about all of this 'vette' stuff, I get to wrench and learn as I go. If I make a mistake, it's actually a positive because I'll never do it again!.

Thanks everybody

 

Well this forum is swimming with non-supporting vendors that malinger here looking to sell you a great deal on their very good high performance part. You haven't told us who but I have a short list of guesses. Yah know if they solicited you by PM -as I suspect - the only way the moderators/supervision will know is if you tell them. You really need to mention this to someone as it will spare others the same pain. I dont know what you have to lose now?

You are an impressive enthusiast as we can read all the work you have done to your car. It's a shame the guys with the most passion for their car are preyed on the most. I can remember American Racing AR engines selling crap motors here until they eventually disappeared. Then there was blockman selling high end aftermarket blocks but well overpriced - he faded out also.

I think there are at least 3 names here that would sell you a motor like that. Only 1 owns a corvette but they all malinger here. I would like to at least know if they solicited you by PM.

Well I can respect your privacy.

Good luck with your new heads.

 

Floating valves makes the lifter lose contact with the cam, not the rocker to the valve. There is no mechanism to pull the rocker back to closed position other than the valve spring.

My suggestion is give the builder the opportunity to make it right. If they don't, please do share facts and save others from your headaches. Don't call them names or question the lack of genetic diversity in their lineage, or their meth use, but share the hard facts. They can't do anything to you legally without proving your facts wrong.

It could be the tip rolling off the edge, or it could be just crappy metal in the valve deforming and spalling off.

Procomp is bottom dollar crappy chinese hardware. I have their 8 stack intake. It took a bit of work to make it into a usable piece of hardware, but it's just an aluminum casting that is under no stress. I would never trust them for things under real stress like crank, rods, any critical moving fastener or any piece of the valve train. God forbid a flywheel begging to explode at 6000 RPM severing my legs. The heads may be salvageable with good valves, springs, retainers, guides and maybe even seats, but by the time you've done that, you might as well buy a new set of trick flow, edelbrock or afr's. Or at least a set of blueprint heads. They cast and make their own. So far I'm happy with my Blueprint 383. I have about 1000 miles, no oil consumption and it still looks like loose honey.

 

Looks like possible bad heat treat on the valve tips. Be nice to see a pic of how the rollers were setting on the stem through valve travel. Either way the heads gotta come off. I myself would pull the heads and put new quality valves in it check EVERYTHING and put it back together. I can't badmouth Procomp heads, I got a set on my car w over 3k mi on it.They look new yet and the car runs great. My 2cs.

 

Thans cardo0, appreciate the comments, I have enjoyed my build immensely, despite the many ups and downs along the way. I emailed the builder today with pictures and data on what I found when I pulled the valve covers, including the fact that the pushrods were too long and the geometry was terrible. Regardless of their reply, I will share it along with the builders name. As you said, I have nothing to lose, and if they step-up and make it right they deserve to be recognized as a company that will do just that. Doesn't make the build quality acceptable, but at least they would stand behind what they put together. Who knows, maybe it was the builders last day when he put together my motor and he just didn't care. Doesn't make the company or the rest of the crew less legit... If they don't step up, I absolutely want to save others from going through this.

My hope is that the builder will send me new valves, seals, retainers, guides, and seats to make this right. I'll reassemble the heads and put them on the shelf for a day when one of my kids gets the bug, and I'll have some heads for them to start their first build with.

Roller geometry was WAY off, I used a sharpie on the valve tip to be able to see the stock pattern and it was all the way to the front edge of the valve tip at full open. No question that was one reason for all the damage. Combine that with poor metallurgy and you have a recipe for disaster. I can't necessarily badmouth Procomp either, the builder sourced another brand of valves and assembled the heads themselves I believe. Waiting for their reply to know for sure what brand they used. Heads are coming off tonight and I doubt there is anything really wrong with them other than the set-up. Any head set-up the way mine were would fail eventually, regardless of quality.

Thanks for all the input guys.

 

Over in C6Z there was bad case of this due to someone forgetting to cap the titanium valve tips. Hardened rockers wore away the soft uncapped titanium valve.

 

Wasn't there any warning signs that something was seriously out of adjustment?

 

Buy your next engine from my friend Mike @ ActiveEngines.com, you will not regret it !