ported LS6 heads, new vs. used
06-22-2013, 02:52 PM
#1
ported LS6 heads, new vs. used so i've been doing some looking around at some LS6 heads, and i've found that most used, bone-stock (i.e., not yet ported) 243/799 castings go for around $350 - $550 or thereabouts, depending on seller.
with porting work on average being around $750 - $800 for a "Stage 1" level port job (for a pro-level port job, not just "some guy" doing it in his backyard workshop), it just doesn't seem cost effective to buy used heads & get them ported, especially since there's a much higher possibility with used heads that you can get junk heads...you can purchase a brand new set of LS6 CNC "Stage 1" ported heads for around $1200.
the only way i can see that it would be worth it is if the used heads are being sold already ported for $450 - $800, and/or if they already have upgraded valvetrain components, like better springs/rockers, etc., AND you already intended to do those upgrades anyway. either that, or if you can get the porting work done for much less, or have the capability of doing it yourself (the majority of people can't do a pro-level port job themselves).
just some food for thought for those of you taking a look at used LS6 heads...unless you don't plan on getting them ported and just putting them on as-cast, i'd just save up and get brand new CNC-ported heads.
with porting work on average being around $750 - $800 for a "Stage 1" level port job (for a pro-level port job, not just "some guy" doing it in his backyard workshop), it just doesn't seem cost effective to buy used heads & get them ported, especially since there's a much higher possibility with used heads that you can get junk heads...you can purchase a brand new set of LS6 CNC "Stage 1" ported heads for around $1200.
the only way i can see that it would be worth it is if the used heads are being sold already ported for $450 - $800, and/or if they already have upgraded valvetrain components, like better springs/rockers, etc., AND you already intended to do those upgrades anyway. either that, or if you can get the porting work done for much less, or have the capability of doing it yourself (the majority of people can't do a pro-level port job themselves).
just some food for thought for those of you taking a look at used LS6 heads...unless you don't plan on getting them ported and just putting them on as-cast, i'd just save up and get brand new CNC-ported heads.
06-22-2013, 04:02 PM
#2
so i've been doing some looking around at some LS6 heads, and i've found that most used, bone-stock (i.e., not yet ported) 243/799 castings go for around $350 - $550 or thereabouts, depending on seller.
with porting work on average being around $750 - $800 for a "Stage 1" level port job (for a pro-level port job, not just "some guy" doing it in his backyard workshop), it just doesn't seem cost effective to buy used heads & get them ported, especially since there's a much higher possibility with used heads that you can get junk heads...you can purchase a brand new set of LS6 CNC "Stage 1" ported heads for around $1200.
the only way i can see that it would be worth it is if the used heads are being sold already ported for $450 - $800, and/or if they already have upgraded valvetrain components, like better springs/rockers, etc., AND you already intended to do those upgrades anyway. either that, or if you can get the porting work done for much less, or have the capability of doing it yourself (the majority of people can't do a pro-level port job themselves).
just some food for thought for those of you taking a look at used LS6 heads...unless you don't plan on getting them ported and just putting them on as-cast, i'd just save up and get brand new CNC-ported heads.
with porting work on average being around $750 - $800 for a "Stage 1" level port job (for a pro-level port job, not just "some guy" doing it in his backyard workshop), it just doesn't seem cost effective to buy used heads & get them ported, especially since there's a much higher possibility with used heads that you can get junk heads...you can purchase a brand new set of LS6 CNC "Stage 1" ported heads for around $1200.
the only way i can see that it would be worth it is if the used heads are being sold already ported for $450 - $800, and/or if they already have upgraded valvetrain components, like better springs/rockers, etc., AND you already intended to do those upgrades anyway. either that, or if you can get the porting work done for much less, or have the capability of doing it yourself (the majority of people can't do a pro-level port job themselves).
just some food for thought for those of you taking a look at used LS6 heads...unless you don't plan on getting them ported and just putting them on as-cast, i'd just save up and get brand new CNC-ported heads.
But your right, its cheaper to buy a set ready to go. Just like it is cheaper to buy a crate engine these days vs re-building. Labor keeps going up.
06-22-2013, 04:44 PM
#3
What sort of power gains/differences are there between LS6, Ported LS6 and after market heads. Like what kind of gain can be expected by slapping stock, used heads on? What about a ported vs after market when running a cam? I'm curios how cost effective each of the options are.
06-22-2013, 04:54 PM
#4
typical gains from just slapping a set of as-cast LS6 heads onto an otherwise stock engine/exhaust car are around 15 - 20 HP, give or take a few.
once you start adding other components like exhaust, cam, etc., there starts to be too many variables to say with any definitive accuracy, so it all just depends on the specs of each component and how well they all work together...especially when you are talking about head/intake porting work...not all porting work is equal in quality.
once you start adding other components like exhaust, cam, etc., there starts to be too many variables to say with any definitive accuracy, so it all just depends on the specs of each component and how well they all work together...especially when you are talking about head/intake porting work...not all porting work is equal in quality.
06-22-2013, 04:57 PM
#5
The machining on a complete assembled new pair of heads for $1200 can not be on the same level as nearly $1000 machining put into customer supplied castings.
Cheap machinery set to run fast can churn out product fast but it wont be as precise as better machinery run slower.
Before you tell me I am wrong I run a CNC for a living and have worked both conditions a cheap machine run hard and a quality machine treated well and there really is a difference.
Besides Texas Speed CNC LS6 heads are $1600. There are some out there for $1200 though.
I am sure some will argue that but when comparing prices ask yourself WHY and HOW prices vary so dramatically. Yes buying new castings saves the trouble of cleaning them and less likely to need guide work or a bolt hole repair, those things aren't the whole story though. I would be wondering if the valvejob is being skipped since the "new" factory one is pristine, or as I said above I suspect inexpensive machinery run fast and HAAS is relatively inexpensive.
Far as buying used modded heads, valvesprings are DISPOSABLE wear items do not consider a pair of heads a bargain because it has used aftermarket springs on it. Once you do an aftermarket cam you need to understand valvesprings are no longer a permanent engine part, they wear out depending on how aggressive the cam is you might be looking at 10-30K miles and the first set I would always be checking byt 10K just so you have a baseline. To many engines have been lost to people treating valvesprings as permanent parts with aftermarket cams.
Cheap machinery set to run fast can churn out product fast but it wont be as precise as better machinery run slower.
Before you tell me I am wrong I run a CNC for a living and have worked both conditions a cheap machine run hard and a quality machine treated well and there really is a difference.
Besides Texas Speed CNC LS6 heads are $1600. There are some out there for $1200 though.
I am sure some will argue that but when comparing prices ask yourself WHY and HOW prices vary so dramatically. Yes buying new castings saves the trouble of cleaning them and less likely to need guide work or a bolt hole repair, those things aren't the whole story though. I would be wondering if the valvejob is being skipped since the "new" factory one is pristine, or as I said above I suspect inexpensive machinery run fast and HAAS is relatively inexpensive.
Far as buying used modded heads, valvesprings are DISPOSABLE wear items do not consider a pair of heads a bargain because it has used aftermarket springs on it. Once you do an aftermarket cam you need to understand valvesprings are no longer a permanent engine part, they wear out depending on how aggressive the cam is you might be looking at 10-30K miles and the first set I would always be checking byt 10K just so you have a baseline. To many engines have been lost to people treating valvesprings as permanent parts with aftermarket cams.
06-22-2013, 06:52 PM
#6
typical gains from just slapping a set of as-cast LS6 heads onto an otherwise stock engine/exhaust car are around 15 - 20 HP, give or take a few.
once you start adding other components like exhaust, cam, etc., there starts to be too many variables to say with any definitive accuracy, so it all just depends on the specs of each component and how well they all work together...especially when you are talking about head/intake porting work...not all porting work is equal in quality.
once you start adding other components like exhaust, cam, etc., there starts to be too many variables to say with any definitive accuracy, so it all just depends on the specs of each component and how well they all work together...especially when you are talking about head/intake porting work...not all porting work is equal in quality.
