[s-cars] Re: Valve Job Anyone?

[Djdawson2 at aol.com]

In a message dated 1/17/04 7:19:17 AM Mountain Standard Time, QSHIPQ writes:

> Er, and Dave, "oh yeah I can reuse them" makes *me* think something 
> different than you might have intended.  Why?
> 

Not sure why you think what you think...  But let's just say that if I want 
to pull my head for any reason, I can without investing in another set of 
stretchies.

You're right... nothing but testimonial here.  But I do prefer to purchase 
things once.  In all my time of working on vehicles, I will offer that I've only 
encountered such studs on Audis and VWs.  A lot of my career was spent on 
high output industrial diesels running upwards of 40psi... on top of 22:1 
compression ratios.  Some even had turbos feeding superchargers air at 32 psi.  Those 
applications... nothing but hardened steel studs.  The explanation was that a 
stud offers the attainment of a more accurate torque value.  You are 
tightening a nut on "visible" exposed threads, with no interference.  No chance of 
gummed up threads in the block giving you a false reading, and no interference 
between the bolt shaft and the head to do the same.

One common VW failure that cost a whole lot more than a stud kit... the head 
bolt holes in the block were not relieved.  If you had residual fluid in the 
bolts hole, when you tightened the head bolts, the resulting hydraulic pressure 
could, and did, crack blocks.  Unfortunately, I've BTDT.  

IMO, why not use studs that are more in line with industry standards in heavy 
duty/high output applications?  Failed headgaskets can result from many 
things.  As you've stated, you've seen failures on cars with studs and stretch 
bolts.  No real good conclusions can be made.  However, my choice is to stick with 
industry "conventional wisdom" rather than the peculiar setup that Audi/VW 
choose to use.  It costs me nothing.
Take care,
Dave