69blueSS

iTrader: (31)

Has anyone else got any results with these heads?? looking to buy a new set of heads and was hoping to see more results from these. Torn between staying rectangular port or drifting back to cathedral

cam75w/ls1

iTrader: (2)

After buying and shipping back 4 sets of rockers it is now understood that you can "ONLY" run stock rockers on these heads. Waiting on the new pushrods to show up so I can check the rocker wipe on the valve stems. It looks way too high right now. It's touching the very edge of the stem on the intake side and by the time the rocker compresses the valve it's barely to the middle. If this isn't corrected by the time the pushrods come in then I'm pulling the heads off. I will not be spinning 7500rpms on a LSX block with weak valvetrain.

Jimbo1367

Cam75w/LS1,

I would imagine the reason TSP sends new rockerstands IS because they are required for the new valve spacing.

cam75w/ls1

iTrader: (2)

Yes,that is correct. When I tried to transfer my Jesels from the old LS7 heads to these I realized I had to use the new stands. But,the rockers won't work. I have ordered Yella Terras,Comp,and then Scorpions. Nothing fits except stock only rockers on their rocker stands.

TVWilkes

Sometimes when you make an aftermarket cylinder head, you have to move things around to make them optimized. Just because gm put them in one spot doesn't mean it was ideal. The problem isn't with the cylinder head. Your salesman should have told you the heads require stock rockers at the time of purchase. In time, I am sure Jesel or other rocker companies will make them for the PRC LS3 head.

mr_biscuitz

iTrader: (22)

if and when will there be a big bore version? Whats the biggest cubic inch these have been put on?

93-Z07

Can these heads be purchased without markings on them so they appear more stealth and like a factory head from the outside?

cam75w/ls1

iTrader: (2)

Yep,the salesman should have also told me they didn't stock the 6 bolt ARP head stud kit and the one of a kind custom Cometic head gaskets for these heads "they" sell. They also told me it would be 3 weeks for the short block and took 4 months. I ordered Morel lifters and they sent Lunati link bars. Now I'm stuck at the pushrods and rockers. Don't get me started...

TVWilkes

The Lunati lifters are made by Morel. Well I do agree with your issues, it's not the products fault. Why would these heads require a "one of a kind head gasket" ?

TVWilkes

No, you would have to grind off the markings. The extra row of head bolts will be very hard to grind off.

93-Z07

LOL okay thanks.

Jason 98 TA

iTrader: (4)

Not sure where the confusion is on the custom cometic gaskets, I'm running a set on stock gaskets on a ls3 engine dyno motor?!?!? Who did you talk to? None of my sales guys know anything about someone wanting a custom gasket!?!?!?

As far as the valve location change it's very simple. We built a cylinder head to be the best possible design we could. We didn't keep GM's far less than ideal valve locations just because it was easier. Instead we built our head with relocated valves for improved power & flow potential. The result of these changes were we had to build a billet rocker pedestal to allow for these changes.

The billet rocker pedestal is included with the heads at no extra charge to the customer so really its a win win for anyone buying the heads.

cam75w/ls1

iTrader: (2)

I understand the head redesign. I quoted this job to a customer thinking the Jesels were going to be reused. He's mad about the stock rockers,which I gave him my own set out of stock free. So my LY6 motor has no rockers. When the short block was shipped w/ the heads,there were no head bolts or head gaskets. So I looked at the original engine quote a little closer. Oh,ARP's quoted for bottom end only,not the upper portion. Called about the head studs,they are on back order and cannot be obtained. I then asked about the head gaskets. It was my fault thinking that if I was ordering a complete motor that it would come w/ all the trimmings. The salesman informed me that Cometic would have to be called for the head gaskets to be made. I called Cometic and they shipped them a week later at the tune of $100 a side. My customer is very pissed off and this will probably be the last time I work on his car at this point. I'm just trying to get through this and hope to god the motor runs well.

Sales4@Texas-Speed

iTrader: (4)

I believe I was the salesperson on this order and I do remember going through all of this. You asked me for a short-block with heads on the side so you can assemble that. If you had ordered a long-block from us and had us assemble it then it would have come with the gaskets and bolts, but short blocks do not include that stuff. If you don't tell me you need it I am not going to add it to the quote. I emailed that quote to you multiple times so there was plenty of time to add those if needed. I was never told that Jesel rockers were going to used on these heads. I never said there was a custom Cometic gasket needed, I just said it had to be made and typically takes a week or two to the customer. This was the point in the conversation you got mad at me and hung up. I apologize for these issues but I don't see how this can be all our fault when I sent quotes asking you to look them over and make sure this is what you want.

Jimbo1367

I would think aftermarket rockers would work, as long as they weren't shaft mounted. Say. Comp ultra Golds.

cam75w/ls1

iTrader: (2)

Heres where I'm at right now. The rockers are only wiping the upper part of the stem. The pushrods had to be lenghtened to 7.5's to get the correct preload on the lifters.




I'm guessing I'm going to have to shim the pedestals up and reorder some more pushrods.......

mr_biscuitz

iTrader: (22)

Whats the biggest bore these have been put on?

BMF_Racing

iTrader: (6)

[QUOTE=Jason 98 TA;15610649]Guys we're shipping the new PRC aftermarket casting LS3 heads! Here's the info:

PRC Aftermarket LS3 250cc CNC Cylinder Heads
base price $2,199.99
item# 199-PRCLS36B250 QUOTE]


Might be a weird question, but would these work on a standard 4 bolt block without any issues? I would love to add these to my 408 rotating assembly but a new LSx block in not in the budget this year.

What's your thoughts (850whp area, 88mm turbo LQ4) on this? I would plan on getting the LSx block to turn it up maybe a year or so later.

TVWilkes

[QUOTE=BMF_Racing;16335418]
The PRC six bolt heads will work great on factory blocks as well as aftermarket blocks.

Sales1@Texas-speed

BMF Racing feel free to give me a call I would be happy to go over your setup with you and get you into a set of heads that fits your build. Also just like TVWilkes said our 6-bolt heads work on stock blocks as well as the LSX blocks.