PREDATOR-Z

Well I finally got them after 7+ weeks of anticipated wait.

PRC 4.8/5.3L Stage 2.5 (2.04 int/1.585 exh), 62cc (unmilled), Platinum PRC springs (max .670 lifts advertised)

Packaging was well done with styrofoam, and bubble wrap in a strong cardboard box. Box was well treated during travel as it shows no signs of abuse.

I will call the heads H1 and H2 for reference:

H 1 inspection feedback:

>Lodged loose titanium retainer in a water passage, came out easily.
>Head deck has one scratch (made by holding clamps or similar tool as the H 2 has the same nick at the same place.
>The intake rocker bolt holes that are now open to the chamber have not been deburred from the inside and there is potentially bits that will dislodge and fall inside the chamber upon assembly.

H 2 inspection feedback:

>Head deck has 3 scratches, one same as H 1, second is between a water jacket and bolt hole (can be nail felt), 3rd in one corner (look like a tool drop nick).
>One water jacket hole in centre of head is halfway blocked by casting imperfection (will need serious grinding to open up)
>One chamber edge has a nick in it and will have to be ground to seal
>Also the intake rocker bolt hole issue.

Overall the CNC job is really good, finishing comparison from chamber to chamber is fairly even.
PRC new Platinum springs on it (looks good).

I will have to do a little cleaning and deburring and opening up the water jacket that is blocked.
I will be using GM graphite gasket since a Cometic will not seal with the scratches.
Overall for the price, they look better than previous PP heads i've seen around.
I'll be doing some measurements over the next couple of days (spring heights, deck thickness, plug protusion etc...)

I took some pics but it will be a couple of days before I can post them.
i'm hands on type of person, so I think I'll be able to finish them carefully before install.

777

iTrader: (21)

You make them sound pretty bad...Not many people would even notice that stuff thouhg. I hope they work out well for you.

JoeyGC5

iTrader: (24)

Thanks for the honest elaboration

Grimes

iTrader: (3)

Cool - waiting for the pics!


Thanks, and make sure to detail your experence as you go along!

PREDATOR-Z

Not at all. The imperfections should be solved with a little grinder and a steady hand.

The only thing that bothers me a little is I wanted to use a .045 Cometic for better quench, but now i can't without milling (which i do not want)

That retainer was in a larger water passage on the inside and could have easily been missed by a newbie installer (I use needle pliers to get it out).
That shouldn't be there IMO, but this is why I scrutinise all parts I get, I take nothing for granted.

The half blocked water passage is difficult to miss.

On the positive side, the CNC job is REALLY good. Hand finishing is good too (chambers).

I'm happy with them, they will work, I'm positive of that.

I just think head deck should be free of nicks and scratches and that chambers should be deburred to reduce hot spots.

The rocker intake bolt holes were not at all rid of bits and burrs that will find their way sooner or later in your chambers (but I can clean those too).

As I said with regards to parts and CNC, they are REALLY good for the price. A little more care will take them to almost perfect level.

Also I will have those flown on a bench, because I have not recieved any flow sheet with them (so I assume they were never flown), but it beats a generic sheet given with some other brand heads that some poeple get.

And BTW just FYI that I've sent an elaborate feedback to the sponsor where I got the heads from, so perhaps they will act on getting these good value heads to the level of perfection they desire.
My analysis soo far is pure cosmeticaly speeking but I'll post more feedback as it goes along, untill we end up with good #'s at the track (but that will be in September)

Orange Peel

iTrader: (20)

Interesting and thanks for the info. I will have to double check mine when they come in as I have never had a set of heads on the car besides the stock ones, and don't know what to look for. Jason @ TSP will be handling my heads after they go to Terry, so hopefully he will notice anything out of the ordinary, as mine are not the standard 2.5's, so he wants to make sure they are right and flow like a banshee!

SouthFL.02.SS

Interesting. Most guys would not have caught the problems. How did they flow?

DrkPhx

iTrader: (15)

I hope everyone inspects new heads when received. He did exactly what should be done. I did the same with my PP's and AFR's.

1fastWS6

iTrader: (3)

Couldn't you just use some spray copper sealant with the Cometics if your concerned with the scratches? I don't see any reason you can't. I think alot of engine builders use that with all MLS gaskets regardless. Might want to ask around. I'd want to keep the tight quench if I were you.

Tony Mamo @ AFR

iTrader: (13)

Not worth the risk (having to pull heads due to a coolant leak).

I would just bite the bullet and have a machine shop clean mill them a few thou....problem solved and you're back in business with the thinner Cometics...

BrentB@TEA

I think the milling may be a problem with the location he is in Tony. I don't know how many good machine shops are in the UAE

PREDATOR-Z

I agree with you Tony, but over here, it is easier to plug a camel's nostrils than to find a trustworthy machine shop to do anything on an LS1.
The only good one capable i know is my direct competition, and one thing I know, is that you never give your foe your weapons to be cleaned.
So, i will bite a bigger bullet and stick with the graphites as I'm pretty sure they will seal.
Oh well I will just have to take my Power steering belt off and run a shortbelt to make up the difference. (I was gonna do that anyways eventually).

Besides we run 98 octane pump gas here so i'll still be able to shoot up to 200 dry on them, regardless of gasket, without too much fear of detonation.
(the little extra power would have been nice as usual but c'est la vie)

LS1FIRE

iTrader: (1)

Im waiting on my PRC heads i hope everything will be okay.

Jason 98 TA

iTrader: (4)

Mark please post pics of the nicks your seeing in the deck surface. After the decking the cylinder heads should look awesome I would be more than happy to cover the costs for decking the cylinder heads if they were hurt during shipping

Mr. Luos

iTrader: (9)

Can't wait to hear about the performance of the heads.
Considering these for my set-up.

Redneck Z

iTrader: (3)

QUOTE: Mark please post pics of the nicks your seeing in the deck surface. After the decking the cylinder heads should look awesome I would be more than happy to cover the costs for decking the cylinder heads if they were hurt during shipping

This is great to see someone willing to stand behind their product. No calling 20 times and having nobody return your call. You know it's a great business when they take the initiative like this. This is how you gain and keep customers. Props to TSP.

SouthFL.02.SS

TSP rocks.

Hardtop

iTrader: (3)

ATVRacer is running PRC's in a full weight car and a shot. Car has run 10.0X at 3600 lbs. I think you will like the heads, he does.

Bruce

TT_Vert

iTrader: (12)

not to bash anybody, but i bet if this wasnt so public stuff like this would rarely happen.
dave

66deuce

iTrader: (1)

the last set of heads i bought had tiny metal shavings in the ports.(left over from the porting)and a couple of the valves were tight in the guides.(due to the heads not being cleaned properly)no matter whose heads/parts you buy,always inspect them carefully before you install them.and no,they weren't PRCs.