Cracked PRC LS6 Head PICS
Cracked PRC LS6 Head PICS Got my heads the other day and was polishing them today and found a crack in one of them. This sucks, but at least I found it before installing them. Also, is there going to be a problem with the seats (see pic). It looks as if some of them are not on straight. You can see how they are not centered under some of the springs. Any advice?? And yes, I will be sending the heads back.
The Crack
Spring seat not centered.
The Crack
Spring seat not centered.
Yeah, I was thinking that but wasnt sure, there are about 6 of the 16 seats that are like that. They said it was OK. They are a very reputable place so I figured that it was OK.
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I dont think that is what happened. Although I have seen this before. The box was in PERFECT condition. Dont see how a crack like that could have happened with a perfect container. 
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You can probably shift the spring over by hand if you try. As for the crack, if they were used heads that PRC did, then no telling what happened. That is a pretty beefy section where the crack is, isn't it? The edge looks smashed or dented in, is the other head dented as well? That might be the source of the crack, but the crack doesn't look clean in the photo, which indicates it has been there a while. If the crack was "clean" then it might have happened when shipped to you.
TECH Fanatic
Joined: May 2003
Posts: 1,292
Likes: 6
From: RainbowCity,Alabama
That head could not have been damaged at TSP, because the head would not sit flat on the newen seat & guide machine. The operator would have noticed it. As far as the spring shim, that is an easy fix. The shims have a .550 hole in them. The guides are .500.This will allow them to shift over some. I don't believe that will hurt a thing.
Wow that cylinder head took a pretty good shot it looks like! We use new castings so that damage had to be done some point after it was cnc ported & had the cnc seat work done. It's not the craziest thing I've seen damaged though, we even had a customer last week only receive one of the cylinder heads that we originally shipped to him! I have about 10 sets going together right now so I can ship you a replacement set first thing in the morning.
What kind of polishing were you doing to the heads? I'm hoping you weren't polishing on the runners any. Guys keep in mind we've worked over 6 months of constant tweaking to that head to make it perform the way it does! Cylinder heads are sensitive parts & moving material around can screw up a good cylinder head!
Please keep all the original packaging so I can give it to the UPS people. They always want the original packaging material when they receive a claim. We've had people get door hinges with their camshaft order, & all kinds of crazy things! This by no means is the weirdest thing I've seen, but it looks like that head to a CRAZY HARD shot!
What kind of polishing were you doing to the heads? I'm hoping you weren't polishing on the runners any. Guys keep in mind we've worked over 6 months of constant tweaking to that head to make it perform the way it does! Cylinder heads are sensitive parts & moving material around can screw up a good cylinder head!
Please keep all the original packaging so I can give it to the UPS people. They always want the original packaging material when they receive a claim. We've had people get door hinges with their camshaft order, & all kinds of crazy things! This by no means is the weirdest thing I've seen, but it looks like that head to a CRAZY HARD shot!
__________________
Jason
Co-Owner, Texas Speed & Performance, Ltd.
2005 Twin Turbo C6
404cid Stroker, 67mm Twins
994rwhp/902lb ft @ 22 psi (mustang dyno) www.Texas-Speed.com
Jason
Co-Owner, Texas Speed & Performance, Ltd.
2005 Twin Turbo C6
404cid Stroker, 67mm Twins
994rwhp/902lb ft @ 22 psi (mustang dyno) www.Texas-Speed.com
Looks like the springs are just sitting on the shims, not a seat. I've seen people do it before, but I personally like the correct seat with the locators on the bottom. If there is no center locator, the inner and outer springs can walk causing excessive wear and early retirment of the springs.
I know that stuff happens. Its not you guys fault. No biggie, anyway, I was just using some mothers polish on the ends of the heads to brighten them up. Especially on the pass side where there is nothing covering it. They had a little stain or two so I was just cleaning them up. I would never POLISH the runners or anything like that. HEHE Guess I should have said cleaning. Oh well, stuff happens and you guys continue to astonish me 
. Jason, I will give you guys a call in the morning. Again, I am not worried, Thanks for everything, and talk to you tomorrow.
. Jason, I will give you guys a call in the morning. Again, I am not worried, Thanks for everything, and talk to you tomorrow.
Originally Posted by Beast96Z
Looks like the springs are just sitting on the shims, not a seat. I've seen people do it before, but I personally like the correct seat with the locators on the bottom. If there is no center locator, the inner and outer springs can walk causing excessive wear and early retirment of the springs.
Gottcha, thanks.
Originally Posted by Beasst8
I was just using some mothers polish on the ends of the heads to brighten them up. Especially on the pass side where there is nothing covering it. They had a little stain or two so I was just cleaning them up.
Originally Posted by Beast96Z
Looks like the springs are just sitting on the shims, not a seat. I've seen people do it before, but I personally like the correct seat with the locators on the bottom. If there is no center locator, the inner and outer springs can walk causing excessive wear and early retirment of the springs.
Guys we do this everyday, do you really think I ship spring kits with spring seats, but leave them off on the heads?
__________________
Jason
Co-Owner, Texas Speed & Performance, Ltd.
2005 Twin Turbo C6
404cid Stroker, 67mm Twins
994rwhp/902lb ft @ 22 psi (mustang dyno) www.Texas-Speed.com
Jason
Co-Owner, Texas Speed & Performance, Ltd.
2005 Twin Turbo C6
404cid Stroker, 67mm Twins
994rwhp/902lb ft @ 22 psi (mustang dyno) www.Texas-Speed.com
Originally Posted by Jason 98 TA
That is absolutely incorrect. There is a spring seat under the spring & the shim is under the spring seat!
Guys we do this everyday, do you really think I ship spring kits with spring seats, but leave them off on the heads?
Guys we do this everyday, do you really think I ship spring kits with spring seats, but leave them off on the heads?
I was looking at the heads last night, now i see what you are talking about. The shim under the seat. Its so clear now
Im so stupid sometimes. No biggie then. Thanks 