I had the prc 260 small bore ls3s and they were a work of art.

Also as others have noted they are clearly not the prc AFTERMARKET ls3 castings since they dont have the 6 bolt tabs. They can be ground off but youd notice it bad been done.

 

Do their ported heads still say PRC on them? That part's confusing me.

 

Yeah they do, I have some PRC ported 243's and they have PRC along with a serial number engraved on them.

 

So were back from our cruise and I'm looking into what PRC as said they have confirmed they are their heads I have not been able to focus on the 260cc point but I will be now.
However the big concern is an intake valve failing like that. I will start making phone calls here shortly I don't think those in AZ are open yet as it's only 10am in Florida and our flight back is not until tonight.

 

Joe has been on top of it seems the intake runners all have cracks from the porting PRC did.

Between Joe and John they have done an outstanding job while I was gone excellent customer service by Joe @ CPR. Talk about dedication Joe thank you again for the service you provide.

Seems like we should know today.

 

They have not answered yet I am hoping that tomorrow (monday) we should have our answer. I am tired of wondering just what I have to do next. I want my car back on the path to being back where it was.

 

I would like to point out the obvious that porting a set of cylinder heads DOES NOT cause cracks in the runners. If that were the case, you'd see hundreds of threads posted up talking about how everybody's ported heads have cracks in them. These heads were purchased from us in May as GM ported castings with stainless steel intake & exhaust valves, as well as a PRC dual spring kit. Can you tell me how much lift you're running on the intake? The stainless steel intake valves are very heavy (122 grams as listed on our website) due to the 2.165" diameter, so you should not be running super aggressive lift (i.e. over .615" total valve lift). I'm not sure if there was a valve float issue that may have bent the valve, which then led to the break. I'm just trying to give possibilities of what could have happened. We have never had a valve failure where it snaps in half out of the blue. There is typically something going on to cause the failure. The thing you can bet on is that whatever issue causes a problem will continue to cause it until it's fixed. A broken valve isn't the cause. It's the result of another issue. The intake and exhaust valves in your cylinder heads came from Manley, so they are quality valves.

Were you sold a set of PRC 260cc cylinder heads? If so, you were ripped off because these are NOT our 260cc cylinder heads, as stated multiple times. I'm sorry that you are having issues, especially on your wedding day. However, a phone call or an e-mail is a much better approach in attempting to get help from anyone instead of cussing our company on a public forum. There's no doubt that something happened, but I don't expect that you were blessed with a random "bad valve". I would expect that there is an issue that is valvetrain related.

Trevor
Texas Speed & Performance

 

The issue has already been identified and sent to PRC since Thursday is my understanding. Updated pictures were sent Friday as well.
The Springs on these heads are the very springs you sold with them supposedly rated to .675. The cam I have is well below that, I will look for the cam card in my records.

This is how it was explained to me:
I am sorry you feel this was not handled as you would have liked but frankly I not only just watched my brand new 6000.00 408 motor go down but I also got to miss an event I paid over 4 months in advance to go to for Corvettes only no longer be an option and I was not able to send out a set of rims on time I had sold as was on my agenda for that morning before going to my own wedding. This was nothing but a nightmare for me and needless to say I am less than happy over the situation. These were brand new never installed fully loaded heads. I replaced my TEA Stage 2 Ported LS6 heads with these because they were supposed to be a better solution and at this point I wish I never had.
Now I have to go back through my 408 and I can assure you when it goes back together it will get 100% Stock OEM LS3 heads with Upgraded Valve Springs again and no further modifications. Lesson Learned with porting LS3 Heads.

You guys may be great, it may have just been a one time thing but these heads have a very clear issue on every intake runner. It caused a failure which has damaged a brand new motor from Loud Pedal Motorsports. I am not out of line to be upset and want it fixed, when it happened it caused a lot of havoc and frankly as I stated before I was not happy about it. How could anyone be?

 

Alright updated pictures added showing Intake Runner Over porting issue.

 

Okay, so let me get this straight. You think that the intake runners are "over ported" because you can see the intake rocker arm bolt in the runner? How in the world would this cause a broken valve??? We have been porting the GM LS3 and L92 head castings since 2008, and you are the only one that has ever had this issue. We literally have thousands of ported LS3 cylinder heads out running without any issues. Are you not aware that the intake rocker arm bolt protrudes into the intake port from the factory? This is why you have to seal the intake rocker arm bolts during reassembly.

I'm not sure who told you that the valve springs are our .675" EHT springs, but they're wrong again. These cylinder heads were assembled using our standard dual valve spring. The lift rating of the valve springs are maximum lift ratings for smaller valves (i.e. under 2.10" diameter). As you go larger in valve size, you also go higher in weight. Again, you're running an intake valve that weighs 122 grams. It's heavy. It sounds like you were sold a set of cylinder heads that were not setup for your application by your shop. I'm guessing that your cam is running over .615" lift, which is the limit we recommend with 2.165"+ stainless intake valves.

So, you tell us they're the wrong heads and the wrong springs. Your information is wrong, and it's very likely that the cylinder heads don't work for your application. You then say that they're over-ported, but they're actually ported very minimally. We did not want to increase the size of the intake runner anymore than we had to for maximum flow and performance. The cylinder heads already have a large intake runner from GM. Our cylinder heads are built for each customer's specific application. Too much lift with a heavy valvetrain can lead to valve float. Valve float can lead to p-to-v contact, which can lead to a bent valve. You see where this is going. Again, I'm speculating as to what could have been the cause of the valve failure. The valves came from Manley. They're quality parts. I know you want to assume that this is a magical bad valve that just failed. However, there is a cause to the failure. I'm trying to provide logical reasoning as to what could have happened, but the only information we are getting in response is "the intake runners are over ported".

Again, I'm sorry that you're having issues. However, the size of the intake runner does not cause a valve failure. They're completely unrelated. If the runners were "ported excessively", the rocker arm bolt would break off in the cylinder head and would actually break a chunk of the top of the intake runner off. The runner size doesn't break a vale. That's a ridiculous claim.

Trevor

 

The information you are getting is the very information I am getting as I understand it. Could I be misunderstanding it very possibly, this is not my area of expertise by any means.

However the pictures I was given and the pictures sent in along with what I am being told is that the heads are the point of failure. I had no issues until now and I was shown these pictures and told here put your finger in there and feel the hole. When I did (This was to the Drivers Side head thats still on) metal flakes came off on my finger. I had no reason to doubt them further.

I am on the IT side of the house for my job and despite a company making the same product every day such as a Lenovo Server that uses the same assembly line and same build every so often one of them comes off that is just not right and it fails in the field. I cannot imagine any process is perfect its just the nature of how things go.

I cannot jump into the game with anything more than the information I am provided as to why my 408 suffered this failure suddenly after putting these heads on. Before these heads it got about 5000 miles put on it with no issues at all. Its been a champ I loved it but I wanted to make the last adjustment I was told that would make this motor everything it should be and that was to move to LS3 Style Heads.

Show me I should be going after someone else, give me the proof and information I need and rest assured I will do so. To me what I care about is that something that was supposed to be rock solid reliable is now down when it never should have been.

I feel confident in making the comment that PTV is normally an Exhaust issue as the Intake Valve is normally open when the Piston is already lowered. I also feel confident that the measurements done before the heads were even torqued down (Twice they were done again my insisting that everything be perfect and checked twice) were right and provided a good amount of extra clearance. I am not sure what more could have been done.
I was told these heads were solid and that everything would be great with them. Obviously I feel differently when they fail.
I used LS3 Factory Rockers, the intakes were all brand new for this job same with the pedestals I ordered everything new and had new TruUnion's installed. Everything was done to insure nothing was left unchecked.

Now I seem to be stuck in the middle of the Installer and the Shop (Both separate entities mind you John does not work for CPR) saying Heads and You guys saying wait this could be something else. To me all I can run with is the information I am given and frankly I have trusted John for years and I have never had an issue with CPR. I have never dealt with PRC until these heads.

I will say this I spoke to Dominic at PRC a little while ago and while it seems I have pissed off Trevor there Dominic seems to understand the situation I am in with these and the information I am getting.

I believe at this point we will get something worked out but I have to say I still think that if they can fix them I will be going to a set of OEM LS3 Heads and just leaving it at that.

Dominic was very professional, respectful and and I felt like he immediately showed he wanted to help solve the issue. At this point I am waiting for Joe @ CPR to get back to me in about an hour and hopefully we can get the situation handled and move forward.

I just want to get my 408 back to where it was Short block wise and then worry about getting OEM LS3 Heads on it and going back to enjoying my car as was originally intended.

 

I totally understand that you're stuck in the middle, and I hate that. We do not have the great reputation that we do by building sub-quality parts or trying to screw anyone. Had you ordered the cylinder heads direct from us, I can tell you for certain that you would've had hollow-stem intake valves. Your .621"/.624" lift is an issue with the heavy valvetrain weight. It's easy to blame the heads as "the point of failure" because that's where you see the damage. The problem is I cannot give you the certainies of who to blame because we do not have anything in our hands. Oftentimes, you end up looking at a catastrophic failure and trying to use reasonable deduction to determine what caused the failure. You can absolutely have a reliable setup again. You just need the correct parts with them. When I say that you could have had valve float issues, this takes on a completely different area for piston-to-valve clearance. Yes, you have plenty of clearance between the valves and pistons when everything is working properly and your valves are opening and closing like they should at the correct time. The problem with valve float is it's not a controlled environment. Your valves will not fully shut during valve float, so now you're hoping that you have enough clearance between the piston and valve at a time when the valve should not be open. You can still have clearance issues with valve reliefs. You/your shop checked p-to-v clearance by slowly rotating the engine over. Valve float was not an issue at this point. The same can't be said when the engine is running. Also, you rarely see exhaust p-to-v clearance issues because the valve is much smaller. Your intake valve is 2.165" diameter, but your exhaust valve is 1.59" diameter. The valve is .575" smaller in diameter. So, you not only gain a TON of room but also a lot less weight due to the smaller size.

Again, we want to help. You're correct that things "could" go wrong. However, we have may QC checks in place during the machining and build process of all PRC cylinder heads to alleviate the possible issue. CNC programs don't change on their own. They can't. If a CNC machine breaks, it doesn't work. It doesn't decide to change a program a little bit, such as "over porting" the intake runners. We also use state-of-the-art CNC equipment for every step of building. We use a 3-axis CNC machine just to mill the cylinder heads! You can read more on the PRC build process at the link below:

http://www.texas-speed.com/t-prcheads.aspx

If the shop is telling you that the rocker arm bolt hole is an issue, that tells me that they are inexperienced with LS-based engines. This is very common on any ported castings. Again, without knowing anything about heads, how would a rocker arm bolt cause the valve to fail? Your picture of the intake runner shows how little we actually remove from the intake runners. You can see a good amount of unmachined area. Ported stock castings are not about making the port pretty with CNC marks. It's all about reshaping the port for best performance and flow without giving up too much port velocity (i.e. making the runner too large).

We are more than happy to help determine what caused what and see what it takes to get you back up and running. Again, the valve breaking is the result not the cause. The correct thing to do is determine the cause, which isn't always the broken part staring you in the face. The definition of insanity is doing the same thing over and over and expecting a different result. If you put the setup together exactly the same, I would expect it to happen again. We will inspect the cylinder heads when they arrive back at our facility. As Dominic mentioned to you on the phone, it would certainly be a worthwhile upgrade to go to hollow-stem intake valves considering your total valve lift.

Trevor

 

Of course it frustrates me when we get cussed on a public forum without even trying to let us help you. This is how we make a living. We have $1 million of CNC equipment sitting in our building that ONLY machine LS parts. I understand that you have a car that doesn't run, but you have to understand that you were sold a set of cylinder heads by another shop that were not correct for your setup. We did our job correctly, and we are getting cussed and bashed for it. I am aware of your posts on local boards as well, so it's unfair to ask for help while still bad-mouthing us elsewhere. Would that not frustrate you? It's not that I don't understand your situation. I understand it completely. It's just not right to publicly bash a company and then ask for their help when someone else sold you heads that weren't correct.

1. They told you they were PRC 260cc heads, and they're not.

2. They told you that they are "loaded", and they're not. They're our base LS3 cylinder heads.

3. They told you that they have our EHT spring kit, and they don't.

I hope you can see the other side of the story. Everything that they've told you is incorrect, but we are blamed for the failure.

Not much left to say. Dominic will be in touch once your cylinder heads arrive and they have been inspected.

Trevor
Texas Speed & Performance

 

To be honest the only reason I called directly was because you asked why I had not. I dealt with who sold them to me because that is my point of contact.

Since it seems you feel me calling you as you asked me why I had not done is now unfair then I will not do so. Frankly I did not know PRC was Texas Speed's Brand when I bought them, I went with what CPR told me was what I needed and would work great for me.

So again you feel I am bad mouthing just you, you feel that I am not checking up on whats going on but in the end I am mad at the product I have that failed on me. Suddenly now I am also wrong for calling as you implied I should. I am sorry but what is it you wanted me to do then? Its obvious I have never bought a PRC part that I know of. Only through the forums here did I learn it was you and on every local forum you speak of every one has the same comment I made about Dominic and talking to you guys today so what else would you like?

As far as what they are vs what I was under the impression they were that's being dealt with directly. I have not over looked it nor will I, but in the end that issue does not handle getting my 408 back to where it was before this failure.
I did tell you, give me what I need to go after the one responsible and I will. I have answered every question I could with what I have available to me. There are pieces I just simply cannot answer because they are above my level of ability. There is not much more I can do at that point correct?

However one universal theme I have heard from every shop I have asked and many others is that they have not seen a failure like this where it snaps the guide too.

 

Where did I say that you shouldn't call us? I never said that. I said that it's frustrating to be bad-mouthed on multiple forums while being asked for help. The guide broke because the valve first bent. An angle won't go through a straight hole. When the valve binds up, something will eventually give way.

 

When I spoke with you I posted about it, I stated how the member of your staff conducted themselves and that I felt they made the effort to handle the situation. That's not bad mouthing you while asking for help that's acknowledging the first contact made since I did not buy them from you nor know to contact Texas Speed originally and what happened which I frankly believed to be positive.

To be honest I thought that before your follow up post we were both on the same page.

 

 

Maybe we are on the same page and we simply are not understanding each other via posts. My issue is with the original post bad-mouthing our company. You state "F___ you PRC heads". It's a moot point at this point because what's done is done. I certainly did not take your compliments regarding Dominic as bad-mouthing. Again, there's no point in hashing previous posts out because it doesn't solve anything in getting you up and running. You also should be enjoying your honeymoon and not posting on a message board!

I will have Dominic contact you once they cylinder head arrives.

Thanks!

Trevor
Texas Speed & Performance

 

Those intake ports have barely been touched, overported lol. Find a new shop, Trevor is right on this.

 

I tried my best to do that last week while we were gone on our cruise but I have to admit at times I was distracted but I seemed to hide it pretty well.

But now I am back and well I hate looking in the garage and feeling like I can't get started fixing it because I don't know whats going to happen. However at this point I am going to say its probably safe that I can start pulling the motor and send it out to be checked. I am really just praying all I need is a new piston.

I see what you mean on the first post I will change that, I agree with you on it.

As for Diet Coke, you do realize I bought these from one shop and had a different mechanic install them and double check what I was doing because I didn't feel I was good enough should something happen.
So which one would you be referring to?