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Do not buy PRC heads, terrible product and bad customer service.
Back story: Around 2 thousand miles after I bought my 09 Z06 a lifter failed. I took this opportunity to replace the heads due to the valve problem. After some research I decided to go with PRC as I didn’t have to send my stock heads to get reworked. I installed the heads and measured the preload. 7.775 pushrods were what I went with. 8k miles later my car developed a misfire. Long story short I found out that cyl 8 had zero compression yes zero. So off came the heads. I was expecting the worst (cracked sleeve or a hole in the piston). On further inspection the intake valve for that cylinder was sucked into the head. The entire spring assembly was higher then the others. Here is a picture of the valve.
The valve was damaged and no longer sealing. I emailed them and they told me to send them in. They told me that they might be able to help me out even if I was a little over the 1 year warranty. So I shipped them the head as soon as I could. Once they checked the heads out they told me it needed a new intake valve as well as some intake guides. They also told me they could not do the work under warranty. I was pissed as I only ran the heads for 8k miles! I told them to send my heads back immediately. They then told me they would “ take care “ of me. I ended up only paying for the intake valve and the guides. Labor was on them. I was still not happy but better than nothing. I then asked them if the heads would %100 ready to go and in spec.
Now after I received the heads I decided to send them to Tony Mamo for some more porting and milling. I also asked him to check every thing out. Turns out more than a few guides are still out of spec. That is what pissed me off the most as they said they would be %100 in spec and ready to go. I almost sold these things before I sent them to Tony! Thank god I didn’t as I’m sure the new owner would have likely just slapped them on as they were recently “checked”. They flat out lied and now I have to replace the guides and will take even longer to get my heads back. I get that I may have gotten a bad batch the first time but to flat out tell me they are ready to go and let the heads go out like that is absurd! Just wanted to let all you know so you won’t make the same mistake I did.
The only good out of this is that I will now have better performing heads as well as reliable heads. I can’t thank Tony enough for helping me out and making these heads right. Outstanding customer service and quality of work. Can’t wait to get the heads back aswell as my new mamofied MSD and get this thing back up and running. End rant.
I see they moved your post..lol No shock there..the guides will wear out even after rework. their good for about 10k miles smh, but that intake valve an the work should have been done at no charge
I see they moved your post..lol No shock there..the guides will wear out even after rework. their good for about 10k miles smh, but that intake valve an the work should have been done at no charge
I would’ve been ok with that but they lied and said they were good to go. If I would have just slapped them back on I could’ve dropped a valve! The worst guide was .0030 I believe.
I see they moved your post..lol No shock there..the guides will wear out even after rework. their good for about 10k miles smh, but that intake valve an the work should have been done at no charge
What is your basis for saying the guide work only lasts 10K miles?
Many on this forum have had their reworked heads for considerably more than 10K miles and have checked them. A very few have had their reworked heads out of spec. For my HCI build the recommended check interval for the heads is 20K miles, I'm half way there. I had a quick check done on them a couple thousand miles ago and they were reported to be fine.
So did the valve make contact with the piston? What exactly failed?
No it didn’t hit the piston. The valve guides were so shot i will post a vid. The compression was bleeding through that valve seat. So it was misfiring. All the intake valves were pretty much shot.
What is your basis for saying the guide work only lasts 10K miles?
Many on this forum have had their reworked heads for considerably more than 10K miles and have checked them. A very few have had their reworked heads out of spec. For my HCI build the recommended check interval for the heads is 20K miles, I'm half way there. I had a quick check done on them a couple thousand miles ago and they were reported to be fine.
From what I've seen from my own heads,
And from all the video's I have seen from my head porter.
Some may last longer not doubting that, but it wasn't a fix for my heads.
As long as people check them at least
No issues with my prc 265 and a few others on here too- I did call them once for info after install and rec'd good service. Hard to tell from your video, I see your hand move more. 6000 miles on mine so far
IMO you've every reason to be pissed, had it been my car I'd have relied on not only heads/labor but builder's word. Yea, severely pissed.
Glad to hear you're getting some satisfaction.
Upside here, & it's a big one, it was caught BEFORE disaster struck leaving you w/ a pile of scrap.
Definitely man, I’m sure people have great luck with them I just would not buy them again. They just push products out and to me it’s not worth taking a gamble.
So the valve stems were hammered further down into the retainers? Again, just trying to figure out what failed. Their Ti intakes don’t require las caps IIRC. What rocker are you running? What springs, retainers, etc? Something must have failed first, which caused the excelerated guide wear due to poor geometry or excessive lash...or something? Weird one for sure...
So the valve stems were hammered further down into the retainers? Again, just trying to figure out what failed. Their Ti intakes don’t require las caps IIRC. What rocker are you running? What springs, retainers, etc? Something must have failed first, which caused the excelerated guide wear due to poor geometry or excessive lash...or something? Weird one for sure...
The valve slammed up into the seat. Yes they’re intake valves DO require lash caps. Not the one piece valves anymore. Oem rockers with smith bros trunion upgrade. PAC .660 springs. Ti retainers I believe. Cam is in the .630 lift if I remember correctly. Lash was setup at zero lash than added .035 to the push rod length.
So the valve stems were hammered further down into the retainers? Again, just trying to figure out what failed. Their Ti intakes don’t require las caps IIRC. What rocker are you running? What springs, retainers, etc? Something must have failed first, which caused the excelerated guide wear due to poor geometry or excessive lash...or something? Weird one for sure...
Look at the intake valve head...their isn't any angle on it like its been beat off an thats why it sunk in the head This could be caused from doing the valve job or from taking the coating off the valve in the valve job
I truly believe it has to due with the coating on the intake valves. Now the exhaust guides being bad I have no idea why.
Bingo. and the guides well welcome to my world I've seen this many times Shame they banned chad or I'm sure he would post videos of the same thing from all diff porters I've seen his videos. He wont even do valve jobs or guide work for the ls7 heads turns people away he ports them only
I would’ve been ok with that but they lied and said they were good to go. If I would have just slapped them back on I could’ve dropped a valve! The worst guide was .0030 I believe.
.0030 man that is bad from a shop like this I don't care who it is. Plus that valve really looks like it had been hammered bad. Glad you got the head off before it really done bad damage.
Really no excuse for crap like this from anyone just goes to show how someone cares about their business or there job in doing it.
Glad you got Tony to get it all worked out for you. Tony does stand behind his all of his stuff & does a great job. Robert
I see they moved your post..lol No shock there..the guides will wear out even after rework. their good for about 10k miles smh, but that intake valve an the work should have been done at no charge
For the record, “they” moved the post, (thread) because it is a complaint about a transaction, and those threads always belong in the Transaction Feedback section.
If there is a misunderstanding regarding why such threads are moved, feel free to PM any section moderator for an explanation as opposed to musing about moderation in the open forum.
03-16-2018, 10:08 PM
Do Not Buy PRC Heads!!
