litemup02

iTrader: (39)

I see..figured their is a little more to it than just flow.

KB99WS6

iTrader: (6)

Still contemplating on what heads to go with...not just between 243's and 5.3's but in terms of whom to order them from. In terms of ported LS6 heads as an example, I can't figure out what the difference is between say a $2000 CNC'd LS6 heads and PRC's $1400 CNC'd LS6 heads. I mean they are both the same exact casting and they are both ported by a machine. I don't understand when people argue how this or that head is so much better. Unless hand porting comes in to play or you are talking about aftermarket heads, why would there be any significant difference? One CNC machine maybe is better than the other? Many people are telling me...oh PRC are cheap budget heads, yada yada yada...but whats the real difference other price?

GMCtrk

iTrader: (23)

I went PRC myself just because I am very confident in TSP.

ls2 bait

iTrader: (11)

it has a lot to do with the program in the cnc machine. each program is set up to do diff things. thats why some have larger cc runners and flow numbers etc. imo if you use an ls6 head or any factory casting for that matter you are limited with what you can do with the head by what gm has already layed out for you. will a head from company a make more power then company b? likely. will it be a 1k or $1500 diff. i dont think so.

KB99WS6

iTrader: (6)

Thats my point....if its the same stock casting...and both are CNC'd by a machine...I can't imagine there is any significant difference.

if you want better it seems you have to go to completely aftermarket heads like AFR's, or TFS, etc....which cost double the price. And do they really produce that much more power? Is it really worth that much more money for maybe 5-10hp?

And therefore it seems the PRC and Patriot heads are a great value. I'm no expert. Just speculating...


Here are some quotes I came across of PRC stage 2.5 5.3's + a 228R cam between this site and ls1gto:

AaronR

iTrader: (8)

The difference in price can be attributed to the quality of valves,springs etc. used.Also you have to consider that the cnc porting is based on a hand ported head and the cnc machine is copying that,and therefore only as good as the original port.

KB99WS6

iTrader: (6)

Well I know the PRC dual gold spring kit is a proven setup. In terms of valves, all I know is they use Stainless Steel valves. Don't know who manufacture's them. In regards to the porting, if all it takes is an original hand port to create the machines specs which will be used on ALL the heads going forward....well, I can't see a company skimping out on that. For lack of a better word, that would be retarded, lol.

GMCtrk

iTrader: (23)

as far as what I was told on the phone, the difference between the stage 1 and stage 2.5 prc ls6's is simply larger valves on the latter. Didn't seem worth $400 to me.

hammertime

iTrader: (1)

If you gave 10 different pro builders 10 sets of LS6 heads to hand port, I can almost guaranty that you'll end up with 10 different port profiles, 10 different volumes, and 10 different TQ/HP curves as tested on the same engine. It's not like there is one guy out there who makes the single best head that money can buy. CNC offers a unique combo of innovation and repeatability in large scale.

I'm sure lots of flow bench testing goes into developing a port before the profile is cut on 7 others for dyno testing. It would be interesting to see how intensive the process can be.

AaronR

iTrader: (8)

There is nothing wrong with the springs on the PRC heads.That would be pretty retarded to skimp on the cost to develop a good port wouldn't it!Or even a good valve job for that matter.

KB99WS6

iTrader: (6)

Ok, I sense your sarcasm on the port Aaron. Well, PRC sells a TON of their heads. Why, if it only takes a one-and-done "master" port, would they skimp on this?? That same port will go into the thousands of heads they sell, which dyno numbers will be pasted all over the internet. It would be completely mindless to skimp on this, unless the best master port costs a $1million these days?

GMCtrk

iTrader: (23)

The PRC 5.3's seem to be a proven combo with the 228r cam. However, what about the stage 1 ls6's and the 228r cam? Which head, the 5.3 or ls6, will make better under the curve power given identical compression ratios? Peak HP?

hammertime

iTrader: (1)

KB99WS6 see my post above, time = money. And sure you can recoup your investment by reselling a TON of heads, but you have to get there first. Then prove it to enough buyers to get some initial sales, then prove it to all the doubters, web finatics, etc.

There are several different approaches, but the most common seems to be to put out a decent product and use good marketing to get a return on your investment. Not that I'm taking away from any of the names mentioned here, everone has their favorite porter, cam grinder, etc. The cost of developing an incrementally better product begins to outweigh the return, unless you do your job marketing.

Justin93

iTrader: (7)

Look at the numbers in my sig, and that is with a 224r cam.. a bit smaller. When I port my FAST Im sure I'll be around 440ish rwhp and 415ftlbs. The 5.3's are a great bang for the buck. Im not saying the 243's arent as well as my buddy has them on his 98 T/A.

Really you can't go wrong with either setup. Do you plan on staying N/A? If so you can have them mill the heads out to bump the compression up a bit which will give you power however you may have to watch your PTV with a 228 but im not 100% sure. Call TSP they would be the best to talk to.

GMCtrk

iTrader: (23)

I'm not sure if you were addressing me or not, but I couldn't run the 5.3s on my LQ9, compression would be too high. So I had to go with 317s milled to 68cc. 10.6:1 static, 8.2:1 dynamic with the 228r 112

KB99WS6

iTrader: (6)

Justin, your numbers would actually be about 10-15rwhp higher without the LS7 clutch and built tranny.

Peetyz

iTrader: (7)

My tuner tells me if i want to go fi go 243's if i want to go all motor which i do go for 5.3's the motor will be extra happy with the compression of around 11:1 KB99WS6 sell ur 243'S someone will def buy them esp with springs and stuff

TheLSgun

iTrader: (7)

Well if your going to sell the 243's. Put me in line!

KB99WS6

iTrader: (6)

Just got off the phone with John @ Texas Speed and decided to order the PRC stg 2.5 5.3's. They will be milled to 60cc which John said would give me just under 11:1 compression. Along with the 228r cam it should be a super-torquey setup that should be really fun and great for the street, especially being my car is so light. And I do have Nitto DR's so traction won't be a big problem.

It just seemed to be the best option for me being its an N/A street car and especially for budget reasons. Since I already bought the Cam kit, those heads were only $940 additional, and I can sell my LS6 heads for ~$400, so it will only cost me ~$500-$550 for the head swap. I also considered having my LS6 heads ported by the machine shop the Vette Docs used which would have cost $1500, but I just didn't have the money. For $1000 less, I should be happy with this setup.

I'll be posting up the dyno results after everything is back together, as well as commenting on how the car feels, etc. The new heads should be ready to ship out in about a week. So I am guessing it will be approximately 2 weeks when its all done.

hammertime

iTrader: (1)

No question you'll be happy with that setup. TSP has a great reputation for quality products and excellent customer service. Look forward to your results.

Good Luck!