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Are head studs worth it?

get new bolts (~$30 or whatever), elring gasket. copper coat the gasket, torque the bolts down, then turn em to 110 degrees instead of 90 (unless they get "gooey" before 110). that's what, like $50 in parts for everything?
 
linuxman51 said:
get new bolts (~$30 or whatever), elring gasket. copper coat the gasket, torque the bolts down, then turn em to 110 degrees instead of 90 (unless they get "gooey" before 110). that's what, like $50 in parts for everything?
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I think I went 115 degrees last time but I didn't copper coat the gasket. Also one use bolts but I checked the length on all of them.
 
VB242 said:
What head are you using? Also I'm planning on going elring again since I bought it from FCP, I'll try out their lifetime warranty.
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398 from 1984. Had it off a while ago (blew hg due to mishap with crank sensor image). Didn't do anything fancy (well, I measured the bolts and scraped off som residue from the old hg) before it went back on the engine :nod:
 
VB242 said:
I think I went 115 degrees last time but I didn't copper coat the gasket. Also one use bolts but I checked the length on all of them.
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Dude head bolts are dirt cheap! Why even would you reuse them? It's hard to tell if the bolts are still good until they break. The bolts stretch and twist during initial torque and stretch more during heat cycles. The next use you're having to put even more strain on the bolt to achieve the same torque value as before. Plus, your final torque value will be lower after angle torque on a used bolt. Bolts are cheap, replace them. Or go big and head stud that jammer.
 
ryan242v said:
Dude head bolts are dirt cheap! Why even would you reuse them? It's hard to tell if the bolts are still good until they break. The bolts stretch and twist during initial torque and stretch more during heat cycles. The next use you're having to put even more strain on the bolt to achieve the same torque value as before. Plus, your final torque value will be lower after angle torque on a used bolt. Bolts are cheap, replace them. Or go big and head stud that jammer.
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If the don't snap they are fine. If they do snap you replace them
 
ryan242v said:
Dude head bolts are dirt cheap! Why even would you reuse them? It's hard to tell if the bolts are still good until they break. The bolts stretch and twist during initial torque and stretch more during heat cycles. The next use you're having to put even more strain on the bolt to achieve the same torque value as before. Plus, your final torque value will be lower after angle torque on a used bolt. Bolts are cheap, replace them. Or go big and head stud that jammer.
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Its pretty easy to tell if TTY bolts stretch. The last b230ft I put together I picked through two used sets of head bolts, 20psi and a small pill later everything is still just fine.
 
I've never liked the TTY bolts.

I've had good luck with the head stud kits. Last two HG jobs I've done I've gone ahead and thrown a set of head studs on the car. At $250+ its not Tbricks cheap, but its not terribly expensive. One was on my wife's 91 with a 94 B230FD motor running an A cam. Studs was terribly overkill, but I'll be able to reuse them forever and I torqued the HG down just a little bit more than stock. The other was my DD high compression B23 with an H cam. Again, I torqued to just a little bit more than stock.

If you have a highly boosted car and want to use a Cometic HG torqued to 100 ft/lbs? Use head studs. If you have a DD low compression B230 that you just want to drive to the store? You can very likely reuse your stock bolts.

In the end, the debate will rage on. Realistically, either will work fine for most of us at our performance levels. In many ways I'm a fan of overkill when it comes to things like fasteners. That way you eliminate one source of potential failure.
 
Lord_Athlon said:
Theyre not TTY bolts. TTY bolts wouldnt be reuseable.
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They're called TTY... even by automotive professionals (it's just one of those things... Most people know it is wrong. They keep using the name anyway.)

But, you are right. The strain induced upon the fastener while torqueing often pushes the lattice of the fasteners constituent metal past the 'yield' point.

This is a good article to become familiar with the practical aspects of the underlying technology:

http://www.enginebuildermag.com/2001/02/threaded-fasteners-torque-to-yield-and-torque-to-angle/
 
I'll admit that I'm not an expert on the subject, but I was under the impression that torque-to-yield was the same as angular torque

The first thing I found on the subject would seem to suggest the same:
http://wbtools.com.au/how-to-understand-angular-torque-and-torque-to-yield/

Just ignore the bold text that says to never re-use them.

Per alldata, Volvo's spec was to not use more than 5 times, don't use if the threaded section shows signs of expansion, don't use if in doubt.
 
Well here's my new fcp purchased ajusa bolts made in esthpana as Conner for real would say. I followed the qr tag to this video for installing them. Interestingly they call for 180? total but the head bolts in the video aren't B2xx head bolts. Also what kind of lube do you think they're using some moly stuff looks like. I've been using motor oil.
http://www.ajusa.es/ficha_multimedia.aspx?referencia=81003900
 
turbotankshane said:
I'll admit that I'm not an expert on the subject, but I was under the impression that torque-to-yield was the same as angular torque

The first thing I found on the subject would seem to suggest the same:
http://wbtools.com.au/how-to-understand-angular-torque-and-torque-to-yield/

Just ignore the bold text that says to never re-use them.

Per alldata, Volvo's spec was to not use more than 5 times, don't use if the threaded section shows signs of expansion, don't use if in doubt.
Click to expand...
If they were torque to yield they would be longer when they were removed instead of being able to be reused. They're skinny in the neck to keep an even clamping force between iron and aluminum as they expand at different rates. The final torquing instruction says to turn them 90? = torque to angle
 
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