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Would You? Head Rework Opinion

Old Jan 29, 2017 | 08:28 PM
  #11  
KingKoopa's Avatar
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I'm not sure I agree with dropping the coin on studs. The stretch bolts are supposed to compensate for block and head growth, taking into account the composite gasket right? On a daily driven application don't studs just excessively stress an already weak block and head?
 
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Old Jan 29, 2017 | 09:23 PM
  #12  
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Having the heads reworked at your trucks mileage is a must, espc with no record of previous work. Does it absolutely need it? Who knows but the cyl heads have to be resurfaced for mating face integrity, guides & oil seals a MUST, and the recutting and sealing of valve seats is an added bonus to an otherwise unknown variable. I didn't want to spend the $ either but it just has to be done; it's too deep into the engine for cutting that corner. That's why it's called a top-end rebuild & not a gasket replacement. Same with the studs; is it completely necessary? Well, wait til you pull some threads out of an aged/compromised aluminum block & cost yourself a bunch of extra time & money or eliminate that variable while gaining the added security of equal torque loading across all 10-points of fastening. The only folks still using stretch bolts are the super-old school & penny pinchers. TTY bolts will become obsolete just like the OEM 198-degree (or whatever it is) thermostat. When you have access & knowledge of known-better parts, you just use that. It costs more but with these rover V8s peace of mind is everything, or have you not read the horror stories??
FYI: i once got a whole gasket kit and freshly rebuilt set of SAI cyl-heads for pennies on the dollar because the guy kept pulling threads out of his block when he went to rebuild with factory bolts and had to give up on it.
 
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Old Jan 29, 2017 | 09:24 PM
  #13  
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Originally Posted by KingKoopa
I'm not sure I agree with dropping the coin on studs. The stretch bolts are supposed to compensate for block and head growth, taking into account the composite gasket right? On a daily driven application don't studs just excessively stress an already weak block and head?
You have this backwards. With studs you take the stress off of the block threads as this is where some get into trouble. I bought a head-studs set before I even had a head gasket leak just to have it.
 

Last edited by chubbs878; Jan 29, 2017 at 09:27 PM.
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Old Jan 30, 2017 | 11:15 AM
  #14  
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The head stud kits are great hence most reputable engine builders use them. You think of most factories use stretch bolts and that's fine and dandy but when you are talking about a older aluminum engine that flexes every time it heats up, it's a no brainer. When you have 10 bolts and some are longer than others, made of different alloys, you have varying torqued across the head. Anybody that has used stretch bolts knows damn well that the final 90 degree turn in almost impossible to get done in one fluid motion so you aren't still getting the proper torque spec. When you use studs, they are threaded in finger tight and then when the head is on, they are torqued in proper sequence in 3 stages so you have an even torque spec arcross the entire head and as an added plus, they are reuseable if you have to do another head gasket job. But to take the heads off and not have them reworked is absurd. You are asking for trouble any way you look at it. It's best to have them reworked and decked and it will serve you better in the long run.
 
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