Torque values

D&J Edgar
Posts: 50
Joined: Mon Feb 23, 2004 1:46 pm

Torque values

Post by D&J Edgar » Tue Mar 01, 2005 9:37 am

On our TABC web site in Technology is a listing of torque values for XPAG/XPEG engines. In looking this over and comparing with other data I have I am finding variances. What is the wisdom of this group on this matter? Figures indicated below are from TABC web site, followed by TD Workshop Manual, followed by Autopress Manual, followed by data from an MG mechanic. All are in ft. lbs. unless otherwise indicated. Rod big end 25, 320 in. lbs (26.6)*, 27*, 20-25 Main caps 63, 750 in. lbs (62.5)*, 62*, 55 Cylinder head 50, 500 in. lbs (46.6), 42, 55 * indicates to next split pin hole Does anyone know where the values on our TABC site came from? What is the most reliable source? If you comment on values please indicate your source. I am not too worried about minor differences but in the case of the cylinder head there is a range of 42 to 55 ft. lbs which is a big difference and it would be nice to know what to shoot for. Also in the case of the split pin hole I have always used the value as the minimum and go to next available slot. I do however switch nuts around until I find a combo where I don't have to adjust up too much. But if I didn't do that, is it possible to exceed the danger point by just going to next slot? Sometimes the indicated torque value is achieved and only half the slot is available so one must go to next slot which is quite a bit. David Edgar, TC 5108 El Cajon, California

joecurto@aol.com
Posts: 313
Joined: Wed Jul 19, 2000 3:42 am

Re: Torque values

Post by joecurto@aol.com » Wed Mar 02, 2005 5:59 am

Dave given the fact that the factory supplied very few torque specs I usually look up general specs for specific type bolts. Regarding that next split pin hole statement that is probably the main reason for T types throwing rod bolt, if you ever inspected a rod bolt after that has been applied you be amazed at the stretch that takes place. I would use loc- tite and be done with it. Joe Curto [Non-text portions of this message have been removed]

1939mgtb
Posts: 143
Joined: Sat Oct 02, 2004 4:43 am

Re: Torque values

Post by 1939mgtb » Wed Mar 02, 2005 11:21 am

Hi Guys, You may not want to use Loctite on a rod bolt. Loctite actually softens with heat after hardening; in fact, Loctite recommends heat application to loosen their Red....and others. Rods get hot. And so does the rest of the engine. I used Loctite to do away with the rod bolt lock tabs on a TR4 engine once, and discovered this the hard way. Who knew you could add oil to the TR4 engine with out removing the oil filler cap? Just pour it in right above the starter motor through the new portal! Use the self locking nuts instead. I think Skip carries them. That way, you don't have to line up the split pin holes by stretching the bolts. ALTHOUGH the correct way to line up the holes is by going to the correct torque value, then checking for hole alignment. If it is off, take loose both nuts and using fine emery cloth on glass, remove a tiny amount of the end of the nut. Re-torque, check hole alignment, etc. Easier to use the self-locking nuts!! On new, wavy, stronger bolts! Best, Ray "Conlige suspectos semper habitos!"
----- Original Message ----- From: joecurto@aol.com> To: djedgar@pacbell.net>; mg-tabc@yahoogroups.com> Sent: Wednesday, March 02, 2005 7:59 AM Subject: Re: [mg-tabc] Torque values > > Dave given the fact that the factory supplied very few torque specs > I > usually look up general specs for specific type bolts. Regarding that next > split pin hole statement that is probably the main reason for T types > throwing > rod bolt, if you ever inspected a rod bolt after that has been applied you > be > amazed at the stretch that takes place. I would use loc- tite and be done > with > it. > > Joe Curto > > > [Non-text portions of this message have been removed] > > > > > Yahoo! Groups Links > > > > > > >

joecurto@aol.com
Posts: 313
Joined: Wed Jul 19, 2000 3:42 am

Re: Torque values

Post by joecurto@aol.com » Thu Mar 03, 2005 5:28 am

Ray to add another point of view on this rob bolt thread, if cotterpins and rod bolt technology were anygood they would still be using them. Joe [Non-text portions of this message have been removed]

1939mgtb
Posts: 143
Joined: Sat Oct 02, 2004 4:43 am

Re: Torque values

Post by 1939mgtb » Thu Mar 03, 2005 6:30 am

True! Best, Ray "Conlige suspectos semper habitos!"
----- Original Message ----- From: joecurto@aol.com> To: 1939mgtb@comcast.net>; mg-tabc@yahoogroups.com> Sent: Thursday, March 03, 2005 7:28 AM Subject: Re: [mg-tabc] Torque values > > Ray to add another point of view on this rob bolt thread, if cotterpins > and > rod bolt technology were anygood they would still be using them. > > > Joe > > > [Non-text portions of this message have been removed] > > > > > Yahoo! Groups Links > > > > > > >

1939mgtb
Posts: 143
Joined: Sat Oct 02, 2004 4:43 am

Re: Torque values

Post by 1939mgtb » Thu Mar 03, 2005 7:10 am

It was written:
> Ray- > Are you serious? I cannot imagine any rod bolt getting hot enough to break > down locktite...I would think torqueing and retorqueing those bolts to > line > up the safety wire holes would prestretch them.
Loctite with the exception of the "high heat" red turns to liquid at 325 F. Yes, this is hotter than you will see in an engine. BUT it begins to soften as it reaches 200 F, and the 3000 psi seal that the red is capable of under perfect conditions is often compromised by oil contamination. Hot oil will soften and sometimes almost dissolve cured loctite, except for the "oil resistant" type. Yes, unless you are using the really good rod bolts, they will stretch every time you torque them. The best way to do this is to use the new "wavy" look bolts (ARP), and the self locking nuts. You will get a good torque reading and a super strong bolt, with no chance of the nut coming loose. This is what I use in my racing engines with no failures to report. Forget the bolts and cotter pin routine! Best, Ray "Conlige suspectos semper habitos!"

davjak@aol.com
Posts: 37
Joined: Mon Jan 19, 2004 8:44 pm

Re: Torque values

Post by davjak@aol.com » Thu Mar 03, 2005 7:37 am

I found some interesting reading on fasteners: _http://www.arp-bolts.com/pages/tech/fastener.html_ (http://www.arp-bolts.com/pages/tech/fastener.html) [Non-text portions of this message have been removed]

ian thomson
Posts: 75
Joined: Thu May 27, 2004 3:26 am

Re: Torque values

Post by ian thomson » Fri Mar 04, 2005 1:36 am

I don't want to appear thick Ray but I am sure that my, and perhaps others knowledge, will be increased if you could tell us what "wavy look bolts" are? Regards Ian Thomson. -------- --- 1939mgtb 1939mgtb@comcast.net> wrote:
> > It was written: > > > > Ray- > > Are you serious? I cannot imagine any rod bolt > getting hot enough to break > > down locktite...I would think torqueing and > retorqueing those bolts to > > line > > up the safety wire holes would prestretch them. > > > Loctite with the exception of the "high heat" red > turns to liquid at 325 F. > Yes, this is hotter than you will see in an engine. > BUT it begins to soften > as it reaches 200 F, and the 3000 psi seal that the > red is capable of under > perfect conditions is often compromised by oil > contamination. Hot oil will > soften and sometimes almost dissolve cured loctite, > except for the "oil > resistant" type. > Yes, unless you are using the really good rod bolts, > they will stretch every > time you torque them. > The best way to do this is to use the new "wavy" > look bolts (ARP), and the > self locking nuts. You will get a good torque > reading and a super strong > bolt, with no chance of the nut coming loose. > This is what I use in my racing engines with no > failures to report. > Forget the bolts and cotter pin routine! > Best, > Ray > > "Conlige suspectos semper habitos!" > > > > > Yahoo! Groups Links > > > mg-tabc-unsubscribe@yahoogroups.com > > > > > >
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Bob Grunau
Posts: 149
Joined: Wed Oct 29, 2003 10:26 am

Re: Torque values

Post by Bob Grunau » Fri Mar 04, 2005 5:51 am

Where can you buy "wavy look " ARP bolts for the XPAG engine? Last time I talked to ARP several years ago they had no rod bolts for the XPAG engine. I agree original type rod bolts with cotter pins are best forgotten. Bob Grunau I don't want to appear thick Ray but I am sure that my, and perhaps others knowledge, will be increased if you could tell us what "wavy look bolts" are? Regards Ian Thomson. -------- --- 1939mgtb 1939mgtb@comcast.net> wrote:
> > It was written: > > > > Ray- > > Are you serious? I cannot imagine any rod bolt > getting hot enough to break > > down locktite...I would think torqueing and > retorqueing those bolts to > > line > > up the safety wire holes would prestretch them. > > > Loctite with the exception of the "high heat" red > turns to liquid at 325 F. > Yes, this is hotter than you will see in an engine. > BUT it begins to soften > as it reaches 200 F, and the 3000 psi seal that the > red is capable of under > perfect conditions is often compromised by oil > contamination. Hot oil will > soften and sometimes almost dissolve cured loctite, > except for the "oil > resistant" type. > Yes, unless you are using the really good rod bolts, > they will stretch every > time you torque them. > The best way to do this is to use the new "wavy" > look bolts (ARP), and the > self locking nuts. You will get a good torque > reading and a super strong > bolt, with no chance of the nut coming loose. > This is what I use in my racing engines with no > failures to report. > Forget the bolts and cotter pin routine! > Best, > Ray

1939mgtb
Posts: 143
Joined: Sat Oct 02, 2004 4:43 am

Re: Torque values

Post by 1939mgtb » Fri Mar 04, 2005 5:57 am

Ian, I apologize. Sometimes I get in a hurry, and forget that everyone doesn't abbreviate in the same strange way I sometimes do.... I refer to the ARP brand bolts as "wavy" bolts. They have a peculiar wavy pattern visible on the side of the bolt. I have used them to 9 grand or so in V-8's with great success. Colloquialisms are funny, aren't they? Recently I wrote one of our UK friends offline to ask what it meant if someone was "an anorak"! I couldn't figure out the connection between rain-gear!! Best, Ray "Conlige suspectos semper habitos!"
----- Original Message ----- From: "ian thomson" i.thomson@talk21.com> To: "1939mgtb" 1939mgtb@comcast.net>; "Mark McCombs" tc8126@core.com>; "mgtabc" mg-tabc@yahoogroups.com> Sent: Friday, March 04, 2005 3:36 AM Subject: Re: [mg-tabc] Torque values >I don't want to appear thick Ray but I am sure that > my, and perhaps others knowledge, will be increased if > you could tell us what "wavy look bolts" are? > > Regards > > Ian Thomson. > > > -------- > --- 1939mgtb 1939mgtb@comcast.net> wrote: >> >> It was written: >> >> >> > Ray- >> > Are you serious? I cannot imagine any rod bolt >> getting hot enough to break >> > down locktite...I would think torqueing and >> retorqueing those bolts to >> > line >> > up the safety wire holes would prestretch them. >> >> >> Loctite with the exception of the "high heat" red >> turns to liquid at 325 F. >> Yes, this is hotter than you will see in an engine. >> BUT it begins to soften >> as it reaches 200 F, and the 3000 psi seal that the >> red is capable of under >> perfect conditions is often compromised by oil >> contamination. Hot oil will >> soften and sometimes almost dissolve cured loctite, >> except for the "oil >> resistant" type. >> Yes, unless you are using the really good rod bolts, >> they will stretch every >> time you torque them. >> The best way to do this is to use the new "wavy" >> look bolts (ARP), and the >> self locking nuts. You will get a good torque >> reading and a super strong >> bolt, with no chance of the nut coming loose. >> This is what I use in my racing engines with no >> failures to report. >> Forget the bolts and cotter pin routine! >> Best, >> Ray >> >> "Conlige suspectos semper habitos!" >> >> >> >> >> Yahoo! Groups Links >> >> >> mg-tabc-unsubscribe@yahoogroups.com >> >> >> >> >> >> > > Send instant messages to your online friends http://uk.messenger.yahoo.com

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