Generation III Internal Engine 1997-2006 LS1 | LS6
Sponsored by:
Sponsored by:

Deciding factor(s) between LS6/243 & 5.3L heads?

Thread Tools
 
Search this Thread
 
Old Oct 27, 2005 | 10:07 AM
  #1  
Pimpium57's Avatar
Thread Starter
TECH Enthusiast
20 Year Member
Photogenic
Photoriffic
Shutterbug
iTrader: (104)
 
Joined: Oct 2003
Posts: 546
Likes: 2
From: Chicago
Default Deciding factor(s) between LS6/243 & 5.3L heads?

I've read a ton about some killer heads out there using both castings for great power/track results (ie TEAs 5.3Ls). I know the 5.3s will raise the compression, but couldn't you mill the LS6s even more? Not worried about having to flycut as they'll be used with a small cam. What should I consider to make my decision between the castings (I will have either one worked over very well)? Thanks!
Reply
Old Oct 27, 2005 | 10:18 AM
  #2  
99blancoSS's Avatar
Banned
iTrader: (115)
 
Joined: Feb 2005
Posts: 9,892
Likes: 3
From: ST Helens, OR
Default

compare results with your setup is the best way to know what to expect. Do a search and look for similar setups and make your decision from the results. I was told by one expert on here that buying my PRC 5.3 heads from Texas Speed was a big mistake and I would be lucky to get 400 rwhp with my cam(tr224). He wanted me to go with the ls6 heads instead for more money. I'm putting down about 440 rwhp and 420tq for $700 less than it would have cost me for similar ls6 heads. Would I have been better with the other heads? hard to say, these heads perform pretty damn good and with about 11:75 to 1 compression my car is snorty. And by the way the tea's arent any better than the TSP/PRC's. I have a graph of my car outpulling tea's and an fm13 all the way to 5800 rpms. I'd go with who ever gives you the better deal on all your parts involved in the swap. Your going to need gaskets and heads bolts and I did my lifters while I was there. Car had 77k on it. Oh ya DART just entered the picture with some very inexpensive heads with slightly lesser flow numbers. Thats another option.
Reply
Old Oct 27, 2005 | 10:40 AM
  #3  
xfactor_pitbulls's Avatar
TECH Addict
iTrader: (16)
 
Joined: Jul 2004
Posts: 2,218
Likes: 0
From: Nevada, TX
Default

Originally Posted by Pimpium57
I've read a ton about some killer heads out there using both castings for great power/track results (ie TEAs 5.3Ls). I know the 5.3s will raise the compression, but couldn't you mill the LS6s even more? Not worried about having to flycut as they'll be used with a small cam. What should I consider to make my decision between the castings (I will have either one worked over very well)? Thanks!
The 5.3 and LS6 heads yeild almost the same compression. If you have to ask these questions to justify your search, that probably means you dont have money to blow(like most of us around here). Pick up a quality stage 2 casting from PRC/TEA/ET or any of the other companies you hear positive feeback about.

Brandon
Reply
Old Oct 27, 2005 | 12:38 PM
  #4  
Brak Attack's Avatar
Staging Lane
iTrader: (10)
 
Joined: Apr 2004
Posts: 82
Likes: 0
From: Panama City, FL
Default

I would go with some LS6 (243) heads and heads don't need to be expensive. I bought my LS6 heads used for $700-. The heads came milled .030 and already had 2.05 intake and 1.60 exhaust valves on them. They had some minor port work done in the bowl area but I then had my close friend fully port them. Including the Manley dual springs, titanium retainers, valve job, port work and cost of the heads I have less than $1200 into my set of 243 LS6 heads. If you keep an eye out on this forum and ebay you can usually run into a great deal on a set of LS6 heads.
Reply
Old Oct 27, 2005 | 01:29 PM
  #5  
xfactor_pitbulls's Avatar
TECH Addict
iTrader: (16)
 
Joined: Jul 2004
Posts: 2,218
Likes: 0
From: Nevada, TX
Default

Originally Posted by Brak Attack
I would go with some LS6 (243) heads and heads don't need to be expensive. I bought my LS6 heads used for $700-. The heads came milled .030 and already had 2.05 intake and 1.60 exhaust valves on them. They had some minor port work done in the bowl area but I then had my close friend fully port them. Including the Manley dual springs, titanium retainers, valve job, port work and cost of the heads I have less than $1200 into my set of 243 LS6 heads. If you keep an eye out on this forum and ebay you can usually run into a great deal on a set of LS6 heads.
I would say that a deal like that is rare. It would be dirt cheap even if you didnt have the 2.05 valves. Dont forget, that requires new intake seats. Most times a set of heads like you have complete would go for ~$1800 used.

Brandon
Reply
Old Oct 27, 2005 | 03:14 PM
  #6  
vettenuts's Avatar
TECH Senior Member
iTrader: (4)
 
Joined: Jul 2004
Posts: 8,092
Likes: 13
From: Little Rhody
Default

Depending on your setup, there is an advantage to the lighter LS6 valves to keep valve train weight down.
Reply
Old Oct 27, 2005 | 05:01 PM
  #7  
equandt's Avatar
TECH Resident
iTrader: (2)
 
Joined: May 2002
Posts: 756
Likes: 0
From: Wish-consin
Default

Bang for your buck, the 5.3 heads are hard to beat in most applications. I would use a 5.3 in most applications unless you absolutely had to squeeze every last HP out of your engine. Otherwise a quality set of 5.3L TEA/PRC/FFHP/ET heads are a good choice.

Pick your vendor after talking with them. They are all great, just use the one that seems to understand your goals best.

Good luck...BTW you can't loose here.
Reply
Old Oct 27, 2005 | 06:22 PM
  #8  
krexken's Avatar
Launching!
 
Joined: Jun 2005
Posts: 202
Likes: 0
From: longview, tx
Default

Don't ls6's have larger runners? I thought lotsa folks used the 5.3s since the port volume is less, slightly smaller chambers and hopefully velocity is better with them.
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

 Verdad Gallardo
story-1

6 Common C5 Corvette Failures and What's Involved In Repairing Them

 Pouria Savadkouei
story-2

Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

 Verdad Gallardo
story-3

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-4

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-5

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo
story-6

Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

 Verdad Gallardo
story-7

Awesome K5 Blazer Restomod Comes With C7 Corvette Power

 Verdad Gallardo
story-8

10 Camaros You Should Never Buy

 
story-9

10 LS Engine Myths That Refuse to Die

 Verdad Gallardo
Old Oct 28, 2005 | 10:57 PM
  #9  
Brak Attack's Avatar
Staging Lane
iTrader: (10)
 
Joined: Apr 2004
Posts: 82
Likes: 0
From: Panama City, FL
Default

Originally Posted by xfactor_pitbulls
I would say that a deal like that is rare. It would be dirt cheap even if you didnt have the 2.05 valves. Dont forget, that requires new intake seats. Most times a set of heads like you have complete would go for ~$1800 used.

Brandon
I wouldn't say it is too rare. You can find 243 heads on the ZO6 forum in the $700- range all day long (there are a couple sets of them on there as I type this). Now I did get the hookup on my port work, it was $200 total for the porting and valve job.
Reply
Old Oct 29, 2005 | 02:24 AM
  #10  
99blancoSS's Avatar
Banned
iTrader: (115)
 
Joined: Feb 2005
Posts: 9,892
Likes: 3
From: ST Helens, OR
Default

Originally Posted by Brak Attack
I wouldn't say it is too rare. You can find 243 heads on the ZO6 forum in the $700- range all day long (there are a couple sets of them on there as I type this). Now I did get the hookup on my port work, it was $200 total for the porting and valve job.
Unless you know someone and get the hook up its usualy like $600 for porting and then $200 for the valve job, so for $1500+ (still need seats) you still dont have them finished with as good of valve springs either. You got a deal and knew someone, unless this guys does he's better off with a new set off 5.3's
Reply
Old Oct 29, 2005 | 12:18 PM
  #11  
xfactor_pitbulls's Avatar
TECH Addict
iTrader: (16)
 
Joined: Jul 2004
Posts: 2,218
Likes: 0
From: Nevada, TX
Default

Originally Posted by Brak Attack
I wouldn't say it is too rare. You can find 243 heads on the ZO6 forum in the $700- range all day long (there are a couple sets of them on there as I type this). Now I did get the hookup on my port work, it was $200 total for the porting and valve job.
You goon, most people dont get that kinda deal. I do, but all the work is done by me. I GOOD valve job is $75 per side, those springs arent cheap either. Quit talking out of your ***.

Brandon
Reply
Old Oct 29, 2005 | 03:10 PM
  #12  
REDSS01's Avatar
11 Second Club
iTrader: (25)
 
Joined: Nov 2004
Posts: 460
Likes: 0
From: Pensacola, FL
Default

http://cgi.ebay.com/LS6-PROFESSIONAL...QQcmdZViewItem

http://cgi.ebay.com/Patriot-ls6-Stag...QQcmdZViewItem

http://cgi.ebay.com/Patriot-performa...QQcmdZViewItem
Reply
Old Oct 29, 2005 | 07:13 PM
  #13  
99blancoSS's Avatar
Banned
iTrader: (115)
 
Joined: Feb 2005
Posts: 9,892
Likes: 3
From: ST Helens, OR
Default

No valves with the first set and you can buy new patriots for less than 1k as well but I wouldnt buy them.
Reply
Old Oct 29, 2005 | 07:54 PM
  #14  
Brian Tooley Racing's Avatar
FormerVendor
iTrader: (13)
 
Joined: Oct 2002
Posts: 1,943
Likes: 7
From: Bardstown, KY
Default

Originally Posted by Pimpium57
I've read a ton about some killer heads out there using both castings for great power/track results (ie TEAs 5.3Ls). I know the 5.3s will raise the compression, but couldn't you mill the LS6s even more? Not worried about having to flycut as they'll be used with a small cam. What should I consider to make my decision between the castings (I will have either one worked over very well)? Thanks!
On a good setup our 5.3 heads are in the 440 RHWP range, our LS6 heads are in the 450 range. We have a new 5.7 (241) program that has made 451 RHWP with Z06 valves, and the "package" of porting and parts, (except for the Z06 valves) is $999 and in our opinion is the best bang for the buck we have ever seen. The LS6 heads will make more average torque then the 5.3, and the 5.3 will make more torque then the 5.7, so it's all in what you want.
Reply
Old Oct 29, 2005 | 08:11 PM
  #15  
Pimpium57's Avatar
Thread Starter
TECH Enthusiast
20 Year Member
Photogenic
Photoriffic
Shutterbug
iTrader: (104)
 
Joined: Oct 2003
Posts: 546
Likes: 2
From: Chicago
Default

I'm going to be running these heads with, as mentioned, a VERY small cam, along with just an LS6 intake and ported stock TB........I'm trying to pinpoint EXACTLY what would suit my needs best. I'm looking for speed, not looking for a dyno freak.

So far, I'm pretty much sold on the 5.3Ls based on the gains per dollar. I've searched thru different setups and it seems that the LS6s are showing little to no gains over the latest 5.3s, and once you consider the cost, the 5.3s are the better buy.

What's the deal with the new 5.7s? I heard they are out, but that's the extent of it. What are the details on the 451rwhp? Seems pretty high, and IF that's a consistent gain/result, then why bother with 5.3s or LS6s......that just tells me you're wasting your cash (I know that's most likely NOT the case). Where else have these 5.7s been tested?
Reply
Old Nov 20, 2005 | 06:58 PM
  #16  
Pimpium57's Avatar
Thread Starter
TECH Enthusiast
20 Year Member
Photogenic
Photoriffic
Shutterbug
iTrader: (104)
 
Joined: Oct 2003
Posts: 546
Likes: 2
From: Chicago
Default

ttt again....I've got the car apart and I'm ready to move on something....

I've got my cam already (short duration with higher lifts).....I was told that the 5.3L are going to be the better choice due to the smaller port volume. Can anyone elaborate more on this? I'm also concerned with what the best valve sizes would be. Thanks for the input so far!
Reply




All times are GMT -5. The time now is 10:47 PM.

story-0
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-1
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-2
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-3
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-4
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-5
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-6
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-7
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-8
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-9
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE