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

706 Castech heads

Thread Tools
 
Search this Thread
 
Old 07-06-2021 | 05:13 PM
  #1  
dave350v8's Avatar
Thread Starter
Teching In
 
Joined: Jul 2021
Posts: 11
Likes: 0
Default 706 Castech heads

Ok I've got the dreaded castech heads, I've seen all over the net that once these crack it's time to throw away. Has anyone managed to weld these up, I'm pretty good with the Tig welder, if I can get access surely these are weldable ??
Over here in the UK Ls heads aren't growing on trees unfortunately

Last edited by dave350v8; 07-06-2021 at 05:21 PM.
Old 07-06-2021 | 05:23 PM
  #2  
RedXray's Avatar
TECH Enthusiast
 
Joined: Mar 2005
Posts: 665
Likes: 380
From: South Carolina
Default

If you look on ebay (US) you'll see 706 heads for sale that have been "upgraded" by tig welding around the effected head bolt holes where the castech heads are prone to crack. Maybe it will give you an idea where to weld.
The following users liked this post:
G Atsma (07-06-2021)
Old 07-06-2021 | 05:31 PM
  #3  
dave350v8's Avatar
Thread Starter
Teching In
 
Joined: Jul 2021
Posts: 11
Likes: 0
Default

Thanks for that info at least it's something to consider whilst I build the motor, the pictures I have seen they appear to crack in the same places, perhaps better to reinforce before they actually crack?

Last edited by dave350v8; 07-06-2021 at 05:59 PM.
Old 07-06-2021 | 06:33 PM
  #4  
G Atsma's Avatar
TECH Senior Member
5 Year Member
 
Joined: Jun 2016
Posts: 21,541
Likes: 3,289
From: Central Cal.
Default

Being aluminum, I would think a well-placed weld should fix a cracked head

Last edited by G Atsma; 07-06-2021 at 09:56 PM.
Old 07-06-2021 | 09:53 PM
  #5  
wannafbody's Avatar
TECH Veteran
15 Year Member
iTrader: (2)
 
Joined: Apr 2006
Posts: 4,817
Likes: 868
From: Pittsburgh
Default

I think trying to weld up and strengthen a non cracked head would produce a large chance for failure.
The following 2 users liked this post by wannafbody:
G Atsma (07-06-2021), Ls7colorado (07-07-2021)
Old 07-06-2021 | 09:56 PM
  #6  
shakenfake's Avatar
TECH Regular
 
Joined: Jun 2021
Posts: 476
Likes: 142
From: Shlumpt, TX
Default

Just JB weld it
Old 07-06-2021 | 11:07 PM
  #7  
wannafbody's Avatar
TECH Veteran
15 Year Member
iTrader: (2)
 
Joined: Apr 2006
Posts: 4,817
Likes: 868
From: Pittsburgh
Default

Originally Posted by shakenfake
Just JB weld it
The answer that never goes out of fashion
The following users liked this post:
G Atsma (07-06-2021)
Old 07-07-2021 | 12:17 AM
  #8  
RedXray's Avatar
TECH Enthusiast
 
Joined: Mar 2005
Posts: 665
Likes: 380
From: South Carolina
Default

Originally Posted by wannafbody
I think trying to weld up and strengthen a non cracked head would produce a large chance for failure.
I'm not sure of the procedure but the e-bay seller/machine shop listing says (sorry for the copy/paste caps)


Originally Posted by RACE114183
REVISED EDITION HEADS WITH SUPERIOR TIG WELDING UPGRADE. THESE HEADS HAVE BEEN REINFORCED BY TIG WELDING AROUND THE FACTORY ISSUE HEAD BOLT HOLES IN THE CENTERS OF THE CYLINDER HEADS
He has a really good feedback 99.2% with 29,487 transactions.




Last edited by RedXray; 07-07-2021 at 12:24 PM.
The following users liked this post:
G Atsma (07-07-2021)
Old 07-07-2021 | 01:22 AM
  #9  
dave350v8's Avatar
Thread Starter
Teching In
 
Joined: Jul 2021
Posts: 11
Likes: 0
Default

Thanks for the link,appreciate the advice guys👍
Old 07-07-2021 | 02:09 AM
  #10  
1FastBrick's Avatar
TECH Senior Member
15 Year Member
iTrader: (16)
 
Joined: Apr 2007
Posts: 9,403
Likes: 483
From: JunkYard
Default

Originally Posted by RedXray
I'm not sure of the procedure but the e-bay seller/machine shop listing says (sorry for the copy/paste caps)

NON SPONSOR LINK REMOVED

He has a really good feedback 99.2% with 29,487 transactions.
Your not supposed to post NON SPONSOR links as there are sponsors that sale heads...

If he has a picture of the modification, you can copy it and paste it here along with the name of the seller.

FWIW, have seens some these heads and while the welds are good the valve job sucks. In alot of cases, the valves should have been replaced. The margine to grind on the factory valves is very thin to begin with.

Last edited by 1FastBrick; 07-08-2021 at 02:45 AM.
Old 07-07-2021 | 09:44 AM
  #11  
cula8r's Avatar
On The Tree
iTrader: (2)
 
Joined: Apr 2015
Posts: 176
Likes: 42
From: East Aurora, NY
Default

The pic in the link ad above shows 317 heads.
In case you're interested someone on LS1tech has a set for 317 heads for 200.00 that'll bump down the compression but can be reworked.
https://ls1tech.com/forums/market/1950773
Old 07-07-2021 | 10:33 AM
  #12  
stockA4's Avatar
TECH Fanatic
5 Year Member
 
Joined: May 2016
Posts: 1,127
Likes: 334
From: St. Louis
Default

reading between the lines I gather you have not confirmed that these heads are actually cracked or damaged for unserviceable or that there is anything actually wrong with them right? The recall was a very very long time ago and I would think that after so many years that if a cylinder head was from a bad batch that was prone to cracking it probably would have crack ed or leaked already not every single castec Head cracks it's just that the heads that do crack for people that like to take pictures for the internet and b**** about it often have the castec stamp That's it, I have a set of stock 706 castec from a 2002 4.8L on my homemade iron 6.2L and they have well over a quarter million unfriendly cumulative miles on them and they haven't cracked and I beat the s*** out of them everyday I actually just finished a double header weekend of autocross in the St Louis heat and humidity and they don't leak they work great they got so hot even that they burned the high temp engine paint off that I tried to put on them to pretty them up but they sure didn't leak, just put the 706 heads on your engine with new valve stem seals and new valve springs and be done with it
The following users liked this post:
G Atsma (07-07-2021)
Old 07-07-2021 | 12:28 PM
  #13  
RedXray's Avatar
TECH Enthusiast
 
Joined: Mar 2005
Posts: 665
Likes: 380
From: South Carolina
Default

Originally Posted by 1FastBrick
Your not supposed to post NON SPONSOR links
Ok Judy I edited out the link...

Uh Oh looks like you're the one with a non sponsor link in your quote

706 Castech heads-2shqsjg.jpg





Quick Reply: 706 Castech heads



All times are GMT -5. The time now is 09:23 PM.