Well just when i thought i had the heads part of my heads and cam swap figured out, Predator Z comes along in another post and has me second guessing my decision. I have decided to do a budget heads and cam swap on my 2000 LS1 do to a missed shift at the track which I am 90% sure bent some valves. I do not however want to spend a fortune on the heads as I still want to go with a larger motor in the future and will most likely use different style heads at that time (this is also the reason I do not want to spend a small fortune on a ported Fast setup and will be retaining the LS6 intake). So given the best bang for the buck options out there i had pretty much decided on TSP's PRC LS6 heads; however, after talking with them and reading numerous of their post about the raging success they have had with their NEW stage 2.5 5.3's, I had decided to go that route. Now I am reading where several people state that the LS6 heads are still the best option and well worth the few extra dollars. Well what does everyone else think? TSP, can you shed some extra light on this subject. I had assumed (yes, I know) that the reason TSP was having such good results with their NEW 5.3 heads was that the heads originally came with a smaller runner than the LS6's (sort of like the made for CNC aftermarket castings) which allowed them to design a CNC program that would flow equally as well as their larger LS6 port, but with a smaller runner volume (similar to their Edelbrock Terminator head which supposedly has a 200 cc runner). Also according to what TSP has stated in some of the other stage 2.5 5.3 head threads, these heads flow better than their LS6 based castings, have smaller combustion chambers, and good p/v clearance (I thought it was equal to the stock valved LS6's but could not find where I got that impression). So what do you all think? Should I go ahead and get the stage 2.5 5.3's based on TSP recommendations, or should I spend the extra $100.00 bucks and go with the LS6 based heads? According to the flow numbers on TSP's site the 2.5 5.3's flow 3-6 cfm more on the intakes than the LS6's between .500-.650.

 

I would def. go with the 5.3's not only do they out flow(i know only 3 cfm more depending on brand) but the extra compression is also gonna give you more power.

I would get some TEA 5.3 Stage 2.5's and call it a day!

If you do decide to go to a bigger motor (4.00+ bore) i would go with a L92 head and a L76 intake, they are cheap and flow like a mothafucka!

Lets us know what you decide!

 

Why spend an extra $300.00 on a set of TEA 5.3's over TSP's 5.3's? Anyone else? In all honesty, if I were going to stay stock cubed or even stock bored, I would most likely go with a set of TFS. But with the L92 and other head options out there for the larger bore motors, I have a feeling these will be temporary which is the reason I have for not going all out.

 

TFS > Cast heads with CNC porting

 

Im taking my car to the shop right now to put on my TSP 5.3 heads.Right now IM cammed (small cam)TR224/112 and put down 348rwhp through a TCI3500 stall A4.Im also adding their powerbond pulley.Ill keep everyone posted as to what it does
john

 

The small chambers of the 5.3L heads will help you to gain back some DCR after the cam swap too, which will reuslt in some more low end power.

 

You are not comparing apples to apples.
you are comparing a 2.04/1.57 valves VS 2.00/1.55
The 2.00 valves WILL have more PTV
As for flow, a LS2 243 with the 2.00/1.55 AND race finish will flow the same.
Add 2.02 valves to that and you'll outflow the 5.3s.
now look at the .200>.400 lifts of the 2 and you'll see that they are equal. The NEWEST 243s only have 230cfm int. runner and you can run a much bigger cam on those without flycutting or sinking valves.

Both are good choices, but 243s are better heads .

5.3L >> $1195
243 >> $949 + $100 (race finish) + $250 for duals = $1299

 

I'm interested to hear what everyone has to say as well. I was going to get the TSP LS6 heads, but someone mentioned the 5.3. I did some research as well as called TSP and that is what they said to go with.

I ordered it already, hope I didn't make a mistake...

 

Im looking at a set of TEA stage 3 5.3L heads, anyone have experience with them?

 

If I was going to spend that amount of money, I think I would go ahead and splurge and get the TFS heads. Anyone else... Anyone from TSP see this thread?

 

Im getting a good deal on them.

 

I would really like to hear from TSP on this. Granted i know i could call them, but I think what they say could benefit anyone contemplating a head swap, plus it would open up their opinion to further debate with those more knowledgeable than myself. I guess the real question is, are they promoting their NEW and IMPROVED stage 2.5 5.3's because they truly are a better product and perform better with more advantages, or just because they are better for the price (meaning a LS6 casting would be better if equipped similarly, just more money), or is it just because they can get the 5.3 castings much cheaper and therfore have a slightly larger profit margin with the 5.3's. Now i am by no means trying to knock TSP (hopefully that is clear), i think either option is a great bargain, it is just I only plan on doing this once with this motor and want the best option out there and a $100.00 difference in price does not make a sacrifice worth while if that is what it would be going with the 5.3's.

 

Some of the things you mention crossed my mind as well, but from my TSP experience, they really work hard at delivering best quality for budget. The 5.3s are that, good bang for $$$ and a couple of hundred dollars cheaper means a lot to some budgeted modders.
Are they better performing heads? Based on a 1 to 1, equal parts VS the 243s, IMO no, as I stated 243s are a better casting. But again equaly equiped 243s are $ 200>250 more.
On big cam applications benefit of the 243s stage 1 are: Bigger runners, PTV (meaning no flycutting) and no need to sink valves.

Try to understand this way:
The best, cheapest heads >>>>5.3s
The best, not as cheap but still good bang/value >>>243s

So if $$$ is your main concern, 5.3s are for you. If you can afford $200 more 243s are better.

 

Actually, the 243's with the stock valves are only $100.00 more. And if the castings are truly better and they give better p/v clearance and have roughly the same size chambers, then i will definately go that route. However, if PRC/TSP was truly able to develop a superior CNC program to utilize the smaller port of the 5.3's to create a better head (as we all know can be done just by looking at an AFR 205 head), and it has a measurably smaller chamber, and does not sacrifice any or much p/v clearance then that will be the way to go. I would not have any p/v clearance problems with the cams I am considering (either the 224/228 LSK grind Pat came up with or TSP's V3) except that I would like to mill them as much as possible to get the compression up. So if I can mill the 243's to a smaller chamber than the 5.3's due to the added valve clearance afforded in the casting in addition to the use of smaller valves then i need to consider that, on the other hand if the 5.3's chamber is already smaller and still will be with less mill then that might be the route to take. I guess what i am getting at is the $100.00 makes no difference at this point, I just need to figure out which head will accomplish my goals the best.

 

what size cam are u going to run?

 

You mean double what you would for the 243 or 5.3 castings.

 

TSP does a good efficient job at getting good output out of the 5.3, but think of what you're saying. They developed a good CNC for them, but they are the ones CNCing the 243s as well.
AFR 205s are a totaly redesigned casting.

.
I really don't know how to spell this, 5.3 2.5 (with unsunk valves) has much less PTV than unmilled 243 stage 1
difference in chambers is ~ 1cc (~63/64)
Let us say that you need 59cc for optimized DCR, then it is a .020mill on the 5.3s and .025 on the 243s (still the 243s will have more PTV)

You should only mill to achieve optimized DCR, not maximum SCR.

Those 2 cams are different animals, you first should choose that to better make a choice on heads. your goals are not set yet.
And even if you were to choose 5.3s, I would still not go bigger than 2.02 valves to seat them properly (and that way you gain a little PTV as well).

 

Predator, I get what you are saying, but I think you might be missing what I am saying. If the 243 have a larger port as cast to begin with, then it will be even larger after the CNC process and there may still be some areas that do not fit the cnc profile exactly causing a disturbance in the runner. Where if you start with a smaller port to begin with you might be able to create a cnc profile that remains smaller yet is still more complete thus translating into better flow even though it is through a smaller port. This is one of the huge advantages to an aftermarket casting is that the runners can be cast very small so that they can be completely cnc'd. At least that is what i have gathered. What I do not know is if this is infact what has happened with the TSP heads or not. I would also like to know from TSP, what size exactly the combustion chambers are. I realize you have a set but I do not know what if anything has changed. In any event, based mainly on your input and a little on what some others have said (allthough most simply state that they agree with you) I am leaning back towards the 243's. As for the DCR/SCR, I know what you are saying, i simply referred to SCR because that is what I figure the size of the combustion chamber directly affects which in turn affects the DCR.

 

The CNC programs on 5.3 and 243 are different.
They are different castings.
Different shape runners.
Intake runner on 5.3 is ~ 220cc
Intake runner on 243s are 230cc (new CNC) and also they have a program for 237cc runners.

Velocity on smaller runners should be a little better (good for small cams), but once you step into 230 range (228+) you'll benefit from more flow out of bigger runners because those cams start working at higher rpms where cfm requirements are higher.

So like I said, choose your cam 1st and match a set of heads (this is kinda backwards, but otherwise choose your heads and match them with a custom grind)

When I ran the "old" version with my 232/234 on stock cubes, the best I could fit was a 113 LSA because of PTV. (2.04/1.575)
In the new version, they sink the valves to clear some more if required by cam.
If you get the 243s stage 1 with race finish, you can run the same cam on a 111 with no PTV issues. Contrary to the hype, this is not a small cam.

BTW a 231/234 is the same as a 232/234 but with a LSK int lobe instead of a XE-R.

 

I have the ls6 2.5 on my car with an MS3 cam(2.04int 1.57exh) -4cc mahle pistons. I going to mill mine for more compresion. there is quite a few people in San Antonio running thus set-up with awsome results. A shop there does a lot of work to F-bodies and vettes with TSP component, just saying if you want to get real world results from people close by. I live in Austin and race in Seguin when I'm at home.