Crownin_Round Posted November 25, 2009 Share Posted November 25, 2009 Got the 7m's head and block decked to run HKS metal hg, would be silly not to upgrade head studs right? So whats the difference between head studs and head bolts, of which ive found you can have either.. And anywhere Jewish I can get either? Link to comment Share on other sites More sharing options...
Yowzer Posted November 25, 2009 Share Posted November 25, 2009 Because you are cranking down a nut on to a stud, there is less friction which = better torque With bolts lots of the torque you are cranking into them is wasted on overcoming the friction Edit: Yes. Nut. Link to comment Share on other sites More sharing options...
Hemi Posted November 25, 2009 Share Posted November 25, 2009 you mean nuts on studs , but yes . mr yowzer is correct . this is why quite a few headgasket torque settings go ftlb or nm setting then a degree setting , this overcomes the problem of the excess drags due to thread. i would go for studs.. that or get new bolts atleast Link to comment Share on other sites More sharing options...
Crownin_Round Posted November 25, 2009 Author Share Posted November 25, 2009 Gonna go ARP either way studs or bolts.. Trying to find the cheapest around though as wallet converted to judaism Link to comment Share on other sites More sharing options...
crooked Posted November 29, 2009 Share Posted November 29, 2009 Studs, the only issue with using studs is you may have to machine the bolt holes to take the larger studs... just from experience with a rb25 block... not sure if it would be the same for a 7m, i was using 12mm arp head studs Link to comment Share on other sites More sharing options...
Mr.Mk1 Posted November 29, 2009 Share Posted November 29, 2009 You plain cant get them cheap. They are a fairly set price from all the sellers ive spied. I need some jew-coin ones too. Link to comment Share on other sites More sharing options...
eke_zetec_RWD Posted November 30, 2009 Share Posted November 30, 2009 You plain cant get them cheap. They are a fairly set price from all the sellers ive spied. I need some jew-coin ones too. email these guys for a quote, i fount them real helpfull, they got me my stuff in from the states but your bolts will be way moire common than pinto shit i would say, www.fabre.com.au bout half the price of any nz place selling the pinto stuff i wanted Link to comment Share on other sites More sharing options...
Dell'orto Posted November 30, 2009 Share Posted November 30, 2009 Or try http://www.41.co.nz they were cheaper than I get get ARP stuff through work for. Link to comment Share on other sites More sharing options...
forced Posted November 30, 2009 Share Posted November 30, 2009 Because you are cranking down a nut on to a stud, there is less friction which = better torqueWith bolts lots of the torque you are cranking into them is wasted on overcoming the friction Edit: Yes. Nut. Eh what? If you read a few books on the subject they always say to clean out the hole and lube the bolt. That way they torque up evenly without sticking. As far as what's better, like everything else the salesman is always going to try to con you out of money and sell you expensive bits that are no better or even worse than stock parts. The only advantage I can see to a stud is if you're planning on pulling it to bits on a regular basis because it keeps breaking. Steve Link to comment Share on other sites More sharing options...
sheepers Posted November 30, 2009 Share Posted November 30, 2009 once again, what you have written is complete bullshit. studs require far less torque to achieve the same clamping force, they put less stress on the threaded hole. there are plenty of reasons why you could use one over the other, but none of them have anything to do with what you said. try at least once to present your thoughts as just that, you thoughts, cauz what you say has got fuck all to do with facts. sheepers. Link to comment Share on other sites More sharing options...
Yowzer Posted December 1, 2009 Share Posted December 1, 2009 If you read a few books on the subject they always say to clean out the hole and lube the bolt. Thank you captain obvious. I own a selection of M series engines. You think I've never had to replace a head gasket? For fuck sake.. Link to comment Share on other sites More sharing options...
forced Posted December 1, 2009 Share Posted December 1, 2009 once again, what you have written is complete bullshit. studs require far less torque to achieve the same clamping force, they put less stress on the threaded hole. . sheepers. You've actually contradicted yourself there. Studs/bolts , whatever, they hold the parts together by "stretching torque". So , regardless, the "stretching torque" is going to put the same load on the block threads, given that the bolt/stud goes in to the same depth. Angular torque of the nut/bolt is converted to stretching torque by the pitch of the thread. A finer thread on the nut (stud) will translate more angular torque into stretching torque than the coarser thread of the bolt in the block. The end result is the same though. The only difference really is that the studs might be able to take more stretching torque than the factory bolts before passing the yield point. If you have to go that far though and over tighten everything then it's more likely that something's broken and you've missed it. I've actually got main studs on my 351 Cleveland block. The only reason I have them is because I've got a main girdle bolted up to it and the main girdle came with it's own ARP studs. I couldn't use the stock bolts because with the girdle they're now too short. Steve Link to comment Share on other sites More sharing options...
Spencer Posted December 2, 2009 Share Posted December 2, 2009 Exert from ARP website, not a sales pitch as they sell bolt sets and studs for most applications Torque Efficiency During engine assembly or maintenance, a bolt must be installed by torqueing it into place. Due to the head bolt’s design, it has to be rotated into its slot in order to engage the threads and secure it into place. This process creates both twisting force and a vertical clamping force, which means that when the cylinders within the engine’s combustion chamber begin accumulating load, the bolt will both stretch and twist. Because the bolt has to react to two different forces simultaneously, its capacity to secure the head is slightly reduced and it forms a less reliable seal in high-powered engines. By contrast, a head stud can be tightened into place without any direct clamping force applied through the tightening. A stud can be threaded into a slot up to “finger tightness,” or the degree to which it would be tightened by hand. Afterward, the cylinder head is installed and a nut is torqued into place against the stud. The nut torque provides the clamping force, rather than the torque of the fastener itself, and the rotational force is avoided entirely. Because the stud is torqued from a relaxed state, the pressure from the nut will make it stretch only along the vertical axis without a concurrent twisting load. The result is a more evenly distributed and accurate torque load compared to that of the head bolt. This ultimately translates into higher reliability and a lower chance of head gasket failure. its pretty simple your torque wrench is reading the twisting force on the bolt aswell as the clamping. With a stud the force is only vertical Link to comment Share on other sites More sharing options...
sheepers Posted December 2, 2009 Share Posted December 2, 2009 steve how many times do you have to be proved wrong and look even more like a fuckwit (if thats possible) before you realize that you don't have a fucking clue what your talking about. Ive seen photos of your work, and all i can say is this, anyone who produces work that looks like a fucking abortion should be treated with a pretty big grain of salt. they dont make salt in big enough chunks to deal with your work. you're an idiot. Link to comment Share on other sites More sharing options...
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