z28poweredlt1

iTrader: (1)

Sooo my PRC stage 1 ls6 heads decided to take a nose dive. One of the rocker collums broke and opened up the intake port to the rest of the head lol.



So I'm trying to decide which heads to replace these with. I'm HOPING TSP will throw me a bone as they told me these were from a bad batch in 05, they arent going to send me free heads or anything but you know some gaskets and free shipping would be great!

Basically I need to know the real differences between the stg 2.5 5.3 heads they offer, and the stg 1 ls6 heads(Much revised since my version) they offer now.

I've done my searching and what not, I want to know if people are making more low end torque out of the 5.3 heads, or more power across the whole board including peak?

Or is there another budget head out there that I should be considering? Keep in mind this is a bang for the buck job, I already bought heads once, I wasn't planning on buying the same heads again to replace them. Nor to I want to spend 2k on a set of non-GM castings.

Anyone had any luck with the trick flow as cast heads? Flow numbers? Dyno sheets? If I'm lucky a dyno sheet with an MS3 cam?

Thanks in advance.

-Mark

jocko

subscribing to this since i'm looking for heads myself.

ramairracer

iTrader: (13)

damn thats the second time ive ever seen that happen, what size cam were you running im concern as what could have caused it

z28poweredlt1

iTrader: (1)

TSP's MS3 cam, ls7 lifters, and the PRC double springs.

J&J Motorsports FL

iTrader: (16)

Damn i'm subscribing too. I have those same heads and cam that I bought about a year ago and still haven't got around to installing yet. I have sold and installed a few sets of these heads with no issues.

CalSpeedPerformance

iTrader: (64)

I would recommend stepping up to the stg 2.5 5.3 heads if you have to pay for the replacements.

They have better valves, often more compression and ive seen better dyno numbers out of the 5.3 heads than the stg 1 ls6's...the stg 2.5' ls6's do slightly out-edge the 5.3's.

z28poweredlt1

iTrader: (1)

Cmon all I know there is more opinion on this board than the presidential debate!

Anyone else?

5.3LJimmy

iTrader: (10)

I would go for the 2.5 5.3 heads because TSP will set them up to work with the MS3 without flycutting. You get aftermarket stainless valves, more flow, and more compression than the stage 1 LS6's.

Jon@Texas-Speed

iTrader: (18)

I'm sorry but we simply can not warranty a head from 2005. Even if you were the original purchaser, our warranty is ONE year to the original purchaser from the date of purchase.

After 3 years, it is hard to positively link this head to the run that had some core shift issue. The ports have indeed been updated since then to add more material to the roof of the port. However, we are constantly updating the port design looking for more air with a smaller volume runner. If you search here you will find more cases like this where the factory casting will break.

https://ls1tech.com/forums/generation-iv-internal-engine/980272-what-all-else-could-wrong.html

For the mods you have, I would go with the PRC 2.5 5.3L heads. They will bump the compression up along with a little smaller CC runner than the LS6 head. Also, we can get these heads to clear with the larger valves. We have numerous cars with these heads and cam making 470+ RWHP without having to flycut pistons!

If you are wanting to go with the PRC heads again, shoot me a PM and I will take care of you on another set. We can set them up without springs for you with new seats and seals installed on the heads so you can just carry your springs, retainers, and locks over to the new heads.

Thanks!
Jon Reynolds

z28poweredlt1

iTrader: (1)

I aprec it Jon, I'll give you a call within the next few minutes.

Jordan S.

iTrader: (17)

I voted other. This seems to be, or was a problem with their heads. I helped my friend pull two off of his car that failed in the same way yours did. After searching some I found out its not an uncommon problem. Its a problem that has happened over and over again, if they won't help you with what seems to be a common problem I wouldnt help them by giving them more money. I see they offereed to help you out in some way. I'm not sure to what that extent is, but if its a good attempt its worth giving someone a second chance.

strokerblackhawk

iTrader: (4)

i just ordered GM stage 3 243 5-axis CNC machined 220cc intake runner. flow 310 Intake 245 CFM exhaust. stainless 2.020 intake valves and 1.575 exhaust valves with super 7 locks dual coil valve springs good to .690 lift. are these good heads or will they do the same thing.

z28poweredlt1

iTrader: (1)

I see where you are coming from. But at the same time, these guys dont make the heads themselves. They're just a distributor.

We'll see what happens though.

z28poweredlt1

iTrader: (1)

As far as I know this was really only happening on an older port design. My heads were 237cc Intake runners, with a 220 you should have plenty of strength left in them. I wouldn't stress about it.

WS6TransAm01

iTrader: (13)

you know me...

CARTEK 4X 243's for the win baby!

times in sig...

white02ws6

iTrader: (7)

you mentioned the trick flow as cast heads, and i would really think about those. from what ive been told they will make power within 3 - 5 percent of the cnc 215s they offer. just my opinion.

z28poweredlt1

iTrader: (1)

Dont think they will work unless I re-spring them, which puts me well over budget.

I'm not sure if they are even compairable to the 2.5 5.3 heads flow wise either. But I may be wrong. Anyone got a flow sheet for these?

magic

iTrader: (4)

Noob questions...I appologize...
But these PRC heads....
1.)Whats PRC stand for?
2.) Are these heads modified GM castings or are they PRC's castings??

z28poweredlt1

iTrader: (1)

Precision Race Components.

Modified GM castings. Basically absolute best bang for the buck on a budget. IMO

strokerblackhawk

iTrader: (4)

how much did you pay for tyhe heads if you don't mind me asking, and what do they flow?