243 Head questions
Thread Starter
Burning Brakes
Joined: Aug 2008
Posts: 850
Likes: 15
From: Vero Beach Florida
243 Head questions
I've been looking around for some 243 heads and a street cam to install on my '02 6spd coupe. I'm hoping to buy a "used but not abused" set of heads to offset cost. I've seen quite a few 243 heads for sale and I need to ask a few questions about the variations of them.
First off, I understand that the LS6 versions have hollow sodium filled exhaust valves. I assume these produce more hp or better performance, and if so, is it a significant amount on a street car? Are there any other differences on the 243 LS6 heads?
Second, it appears that that there are several variations or revisions of the 243 heads. What would be the best one to look for, and how will I know which one it is?
Finally, is there anything special I should look for or check out when buying a set of these heads?
I appreciate any learned advice. Thanks, Mike.
First off, I understand that the LS6 versions have hollow sodium filled exhaust valves. I assume these produce more hp or better performance, and if so, is it a significant amount on a street car? Are there any other differences on the 243 LS6 heads?
Second, it appears that that there are several variations or revisions of the 243 heads. What would be the best one to look for, and how will I know which one it is?
Finally, is there anything special I should look for or check out when buying a set of these heads?
I appreciate any learned advice. Thanks, Mike.
Tech Contributor
Joined: Jan 2007
Posts: 19,353
Likes: 1,125
From: Dyer, IN
I believe the sodium filled valves did not start until 2002. The 2001 LS6 heads should have shorter valve stems, and are non-sodium filled.
Team Owner
Joined: Sep 2003
Posts: 43,084
Likes: 33
From: Raleigh / Rolesville NC
there are the GM 243 heads ( LS6) with light wt valve train,
and many many aftermarket 243 heads. Most of them are very very good. but not all of them.
if budget is your need, there are some budget 243 heads that give great performance and will run very well. Just keep cam lift will under .600 no matter what cam or spring combo
TSP, Livernoses, Patriot ect are all excellent heads
for example only:
PRC Stage 1 L5 CNC $1,025
http://www.texas-speed.com/SHOP/item...d=649&catid=40
and many many aftermarket 243 heads. Most of them are very very good. but not all of them.
if budget is your need, there are some budget 243 heads that give great performance and will run very well. Just keep cam lift will under .600 no matter what cam or spring combo
TSP, Livernoses, Patriot ect are all excellent heads
for example only:
PRC Stage 1 L5 CNC $1,025
http://www.texas-speed.com/SHOP/item...d=649&catid=40
Thread Starter
Burning Brakes
Joined: Aug 2008
Posts: 850
Likes: 15
From: Vero Beach Florida
Thanks Lucky and AU N EGL. Thats some good info. I checked out those PRC Stage 1 L5 CNC heads. Very interesting, but probably a step or two up from what I had in mind. I was thinking maybe a set of low mileage LS6 heads from a person that was stepping up to heads like those.
Then again, If a person was to do all of this work, then why not just go ahead and get something a bit better. I know that its what you want, and how much you're willing to spend.
What I want is this. 415-425 rwhp with appropriate rwtq to take car to track on rare occasion and run a high 11, yet still be able to jump in car and go from Florida to Oregon without problems because of added performance additions.
Car has Z51 package with 3.42s, Kooks headers/hiflow catted X-pipe, and Corsa Touring catback exhaust. The '02 also has the LS6 intake and I have installed a Vararam vrb2 cai, and a Predator tune. I figured the LS6 heads with the proper street cam should get me to where I want to be.
Any thoughts on this, or perhaps some head/cam recommendations?
Thanks , Mike.
Then again, If a person was to do all of this work, then why not just go ahead and get something a bit better. I know that its what you want, and how much you're willing to spend.
What I want is this. 415-425 rwhp with appropriate rwtq to take car to track on rare occasion and run a high 11, yet still be able to jump in car and go from Florida to Oregon without problems because of added performance additions.
Car has Z51 package with 3.42s, Kooks headers/hiflow catted X-pipe, and Corsa Touring catback exhaust. The '02 also has the LS6 intake and I have installed a Vararam vrb2 cai, and a Predator tune. I figured the LS6 heads with the proper street cam should get me to where I want to be.
Any thoughts on this, or perhaps some head/cam recommendations?
Thanks , Mike.
Safety Car
Joined: Dec 2004
Posts: 3,526
Likes: 18
From: Santa Fe TX
LS2 heads are 243 heads as well.
Not sure if the sodium valves make a SOTP difference.
It is my opinion that the 243 heads flow well across the powerband and that any porting or polishing only helps the peak numbers.
I could be very wrong.
In fact going from LS1 with stock manifolds to 243 heads with longtubes, I only noticed a difference at the high end of the RPMs. I already had a mild cam.
Not sure if the sodium valves make a SOTP difference.
It is my opinion that the 243 heads flow well across the powerband and that any porting or polishing only helps the peak numbers.
I could be very wrong.
In fact going from LS1 with stock manifolds to 243 heads with longtubes, I only noticed a difference at the high end of the RPMs. I already had a mild cam.
Last edited by jedblanks; Apr 29, 2009 at 01:39 PM.
Burning Brakes
Joined: Nov 2003
Posts: 1,234
Likes: 5
From: Herriman UT
It might be tough achieving 400+ HP with stock LS6 heads and a "street" cam. My 97 A4 with LS6 heads & intake, Comp 224R cam (224/224, .581/.581, 114 LSA), Kooks long tubes, Ti exhaust and Vararam made 380 RWHP & 380 RWT with a good dyno tune. A bigger cam or better flowing heads would probably get you there.
Thread Starter
Burning Brakes
Joined: Aug 2008
Posts: 850
Likes: 15
From: Vero Beach Florida
It might be tough achieving 400+ HP with stock LS6 heads and a "street" cam. My 97 A4 with LS6 heads & intake, Comp 224R cam (224/224, .581/.581, 114 LSA), Kooks long tubes, Ti exhaust and Vararam made 380 RWHP & 380 RWT with a good dyno tune. A bigger cam or better flowing heads would probably get you there.
Wow Jedblanks, the longtubes and 243s really didn't show that much until top end huh.
AMP Racing
Joined: Aug 2006
Posts: 10,753
Likes: 588
From: Washington TWP NJ
2023 C5 of the Year Finalist - Modified
2017 C5 of Year Finalist
St. Jude Donor '09-'10-'11-'12
Plenty of people make good power with stock 243 heads. It's all in the cam, and what your goals are. With the right cam, you can make 450+ but your drivability will be sucky. The 224 as mentioned above is really mild and very streetable. perhaps go with something a bit bigger.
Talk to the tuner/install shop that will be doing the work and get their recommendations. And call some of the vendors on here - they can recommend something that will work very well.
Best of success with your project
Talk to the tuner/install shop that will be doing the work and get their recommendations. And call some of the vendors on here - they can recommend something that will work very well.
Best of success with your project
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
2027 Corvette vs The World: Every C8 vs Its Closest Competitor
Joe Kucinski
10 Most Common Corvette Problems of the Last 20 Years!
Joe Kucinski
Team Owner
Joined: Sep 2003
Posts: 43,084
Likes: 33
From: Raleigh / Rolesville NC
243 heads will need a bigger then stock cam to get to 400
I also run the comp 224r cam as well but use comp 918 srpings TPIS LTs Random Tech high flow cats & X pipe then straight pipes. my own CAI
400 rwhp and 405 rwtq
I also run the comp 224r cam as well but use comp 918 srpings TPIS LTs Random Tech high flow cats & X pipe then straight pipes. my own CAI
400 rwhp and 405 rwtq
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
You need a CAM. There are too many grinds to even start to mention. Find one that gives you good low to mid range power. ENGLANDGREEN has a wide variety of cams and a few choices of good relaible and streatable daily driver cams. Give him a call for advice, great cams and he can even provide you the CORRECT tune that you will need to make that combo run like you need it to.
If your ripping off the heads, go for the "rest of the story"
- Heads
- Cam
- LS2 timing chain
- CORRECT LENGTH PUSH RODS
- Powerbond harmonic damper
- ARP head studs and ARP Damper bolt
- ARP damper and ARP head studs (there amazing)
- Make sure that you have the up-dated OEM lifter buckets. If they have the number 10 stamped on the underside, get new buckets.
The LS1 OEM heads and the Sodium filled ZO6 2002+ 243 heads take two different length push rods. Make sure that if you get ZO6 243 heads, that you get the correct length push rods.
The HP addiction only gets worse as time goes by.... Been there recovering from that! Im in therorpy but its NOT helping!
Good luck on your HP quest.
BC
If your ripping off the heads, go for the "rest of the story"
- Heads
- Cam
- LS2 timing chain
- CORRECT LENGTH PUSH RODS
- Powerbond harmonic damper
- ARP head studs and ARP Damper bolt
- ARP damper and ARP head studs (there amazing)
- Make sure that you have the up-dated OEM lifter buckets. If they have the number 10 stamped on the underside, get new buckets.
The LS1 OEM heads and the Sodium filled ZO6 2002+ 243 heads take two different length push rods. Make sure that if you get ZO6 243 heads, that you get the correct length push rods.
The HP addiction only gets worse as time goes by.... Been there recovering from that! Im in therorpy but its NOT helping!
Good luck on your HP quest.
BC
Thread Starter
Burning Brakes
Joined: Aug 2008
Posts: 850
Likes: 15
From: Vero Beach Florida
Thanks again for the all the good info. What I'm trying to determine now is, can I have a cam that will run in the 11s, and still be able to drive on trips, etc.? Streetability is most important quality that I want to keep.
I know that some will say go with gas or SC. I'd like to keep it all motor, and I'm sure SC is out of my budget at this time.
Any other thoughts on this are appreciated.
I know that some will say go with gas or SC. I'd like to keep it all motor, and I'm sure SC is out of my budget at this time.
Any other thoughts on this are appreciated.
Pro
Joined: Feb 2006
Posts: 594
Likes: 5
From: O Fallon MO
I nailed down 450 but I did quite a bit to get there.
Patriot heads & cam
Yella Terra's
Comp push rods
FAST 90
LS2 TB
Honker
fuel rails
LG Streets no CATS
GHL Bullets
Powerbond underdrive pulley
PBJ tune
Patriot heads & cam
Yella Terra's
Comp push rods
FAST 90
LS2 TB
Honker
fuel rails
LG Streets no CATS
GHL Bullets
Powerbond underdrive pulley
PBJ tune
AMP Racing
Joined: Aug 2006
Posts: 10,753
Likes: 588
From: Washington TWP NJ
2023 C5 of the Year Finalist - Modified
2017 C5 of Year Finalist
St. Jude Donor '09-'10-'11-'12
How far into the 11s do you want to go?
I would think 243 heads, a 228/230 .600 lift on a 114 LSA with a full exhaust and supporting mods would get you there.
A4 or MN6?
Drag radials too.
It doesnt take much to get these cars into the 11s.
Have you gone to the track yet?
I would think 243 heads, a 228/230 .600 lift on a 114 LSA with a full exhaust and supporting mods would get you there.
A4 or MN6?
Drag radials too.
It doesnt take much to get these cars into the 11s.
Have you gone to the track yet?
Thread Starter
Burning Brakes
Joined: Aug 2008
Posts: 850
Likes: 15
From: Vero Beach Florida
How far into the 11s do you want to go?
I would think 243 heads, a 228/230 .600 lift on a 114 LSA with a full exhaust and supporting mods would get you there.
A4 or MN6?
Drag radials too.
It doesnt take much to get these cars into the 11s.
Have you gone to the track yet?
I would think 243 heads, a 228/230 .600 lift on a 114 LSA with a full exhaust and supporting mods would get you there.
A4 or MN6?
Drag radials too.
It doesnt take much to get these cars into the 11s.
Have you gone to the track yet?
I keep reading these nightmare stories about DRs ripping up stock rears and tq tube bushings. Guess I better add some money back there too.
By the way Capthuff, I moved down here from Northvale in 06. Still miss Bergn County some.
Team Owner
Joined: Sep 2003
Posts: 43,084
Likes: 33
From: Raleigh / Rolesville NC
learn to easy on the throttle. Roll the throttle to the floor, dont stomp on it.
I can spin my 335 hoosiers in 4 gears if I really try
it can be kinda scary spinning the 335 hoosiers when shifting from 3rd to 4th gear at 102 mph
scarier if you lift off
I like small cams, they give far better throttle response then mid size or big cams.
I can spin my 335 hoosiers in 4 gears if I really try
it can be kinda scary spinning the 335 hoosiers when shifting from 3rd to 4th gear at 102 mph
scarier if you lift off
I like small cams, they give far better throttle response then mid size or big cams.
Last edited by AU N EGL; Apr 29, 2009 at 07:28 PM.
AMP Racing
Joined: Aug 2006
Posts: 10,753
Likes: 588
From: Washington TWP NJ
2023 C5 of the Year Finalist - Modified
2017 C5 of Year Finalist
St. Jude Donor '09-'10-'11-'12
Thread Starter
Burning Brakes
Joined: Aug 2008
Posts: 850
Likes: 15
From: Vero Beach Florida
learn to easy on the throttle. Roll the throttle to the floor, dont stomp on it.
I can spin my 335 hoosiers in 4 gears if I really try
it can be kinda scary spinning the 335 hoosiers when shifting from 3rd to 4th gear at 102 mph
scarier if you lift off
I like small cams, they give far better throttle response then mid size or big cams.
I can spin my 335 hoosiers in 4 gears if I really try
it can be kinda scary spinning the 335 hoosiers when shifting from 3rd to 4th gear at 102 mph
scarier if you lift off
I like small cams, they give far better throttle response then mid size or big cams.
ride Thats what I'm looking for!
Le Mans Master
Joined: Aug 2005
Posts: 5,130
Likes: 3
From: Winter Park FL
I may have a set of 243s and a decent street cam for sale soon. The 243s were dented during shipping on the corner. The uneven surface was filed down and will not effect its ability to seal. I'd still recommend milling them to clean up that area and the rest of the surface. I assume you would mill them anyways to ensure a flat surface and lower compression. The cam I will be selling is a Cartek 2X cam, specs are 224/228 .590 113 lsa. Excellent cam for a street car. Just be sure its not to small or you will be swapping it fora bigger cam in no time like me. 