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FE Power Forums => FE Technical Forum => Topic started by: fekbmax on October 31, 2015, 12:04:18 PM

Title: head and main studs
Post by: fekbmax on October 31, 2015, 12:04:18 PM
maybe a dumb question but,
im curious about stud threads on the block side of the studs. the recommendations have changed a great deal over the years, through the 80's and a good portion of the 90's it was recommended to use lock tight on the block end. i have a old late 80's  instruction sheet from milodon main studs that say to use lock tight blue. things changed after that and now i have seen builders use everything from lock tight to oil to anti seize to nothing at all. i totally understand using some kind of lube or ARP assembly lube on the nut end but whats the best thing to do on the course block threads of studs ? not talking head bolts or main bolts but studs only. lots of the roundy round engine builders both asphalt and dirt around here still use lock tight on the block side. of-course i know when in doubt follow the stud manufactures instructions but im wondering what and why they have changed . 
Title: Re: head and main studs
Post by: blykins on October 31, 2015, 12:17:01 PM
I don't use threadlocker on main/head studs.
Title: Re: head and main studs
Post by: jayb on October 31, 2015, 01:02:18 PM
I always use anti-seize, but mostly my studs are going into aluminum blocks.  Shelby recommends torquing the studs to 10 ft-lbs when they are installed, but I think finger tight is probably OK.
Title: Re: head and main studs
Post by: cjshaker on October 31, 2015, 01:09:25 PM
Unless you install the studs and torque them immediately, using any form of locking compound would be a really bad idea. The reason being that it would keep the threads from fully engaging after it's hardened, if they're installed loose. And I don't see any real reason for using it in the first place. There's also no real reason to use any form of anti-seize compound because you're not placing any form of lateral stress on the threads by tightening them in a twisting motion. Just good old oil is all I've ever used on the block side of studs. On the threaded side, you'd best follow the recommended guidelines real close, based on the lubricant used, if you're not using the stretch method.

Edit: Jay brings up a good point about aluminum blocks. I've never had to worry about that. I'm also of the mindset that it's important to cycle all critical studs and bolts several times so that thread engagement is maximized and they're "fitted" together.
Title: Re: head and main studs
Post by: plovett on October 31, 2015, 04:35:31 PM
Finger tight here.  I don't know if that's correct, but they've been in there for years with no issues.  I thought finger tight was a rule for studs in general.

JMO,

paulie
Title: Re: head and main studs
Post by: fekbmax on October 31, 2015, 05:46:49 PM
Thanks guys, I was just curious. I been doing the light bit of oil and just a touch more than finger tight for years. I'll continue on doing so. I was just in a well known roundy round shop in my area and seen them doing the lock tight blue old school and it made me wonder...
Title: Re: head and main studs
Post by: Barry_R on October 31, 2015, 07:33:20 PM
Also just a touch tighter than hand with oil or ARP lube here.  The Shelby studs and some race guy use a elongated tip or a ball bearing at the base of the threads to keep the stud from "cocking" in the hole or side loading as the thread get tightened.
Title: Re: head and main studs
Post by: cammerfe on November 01, 2015, 10:57:27 AM
It's always been my practice to be sure that the threads don't 'bottom' in the hole due to the possibility of inducing cocking. Years ago I did use threadlocker but when doing so it's necessary to put a load on before set-up of the locker so as to not induce any cocking. Threadlocker does make it unlikely that you'll pull a stud out when disassembling.

KS
Title: Re: head and main studs
Post by: My427stang on November 01, 2015, 12:03:27 PM
The ball bearing idea is pretty clever
Title: Re: head and main studs
Post by: fekbmax on November 01, 2015, 01:34:47 PM
some of the newer pro series studs actually have a tit or elongated tip on the end of them  ..