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Preferred method for torquing headbolts?

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Hi everyone, I'm almost ready to start reassembling the top end of my 4L OHC engine and I'm finding conflicting information on which technique is best for torquing up the headbolts.

I'm using a Permaseal MLS headgasket (with new headbolts of course) and the paperwork shows the usual 30Nm + 120 degrees method that's normally used with steel headgaskets.

But I've found that workshops such as Real Dyno Performance (RDP) and Jim Mock Motorsports (JMM) apparantly use a 3 stage torque method...

Stage 1- 40Nm

Stage 2- 80Nm

Stage 3- 110Nm

Has anyone personally tried the 3 stage technique themselves?

To me it appears to be the more accurate method to use, but I'd really like to hear what experiences you guys have had with either before I try the 3 stage technique myself.

As always, I appreciate any info/advice you guys can share.

Thanks guys.

 

Jay.

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Go by the book, or instructions in aftermarket gear.

 

Though that said, I've only ever bolted on one head (not a ford one), and that was done via the following method.

 

-Do all head bolts hand tight (I did this in 2 passes, also, if there is a sequence to follow, follow it)

-Torque headbolts up to specified nm

-Mark all headbolts with a paint marker or such (all the markings should be identical, ie: pointing 12 o clock

-Torque all headbolts an additional 90 degrees CW in sequence (use the dots as a reference, they should all line up once done

-Torque all headbolts a further 90 degrees CW in sequence

 

So far the HG seems to be ok :)

 

Make sure you take your time, follow the torquing sequence, and have a fairly accurate torque wrench

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The bolts are Torque To Yeild bolts, so I was thinking that the torque + degrees method was the typical way to go about it, but then saw that a couple of well know workshops went with the 3 stage method, so it had me thinking...

Mind you, they didn't state that they were using studs or bolts either.

The manual isn't much help, as it only describes how it's done with the composite type headgasket (40Nm + 90 degrees).

Permaseal do tell you that it should be done at 30Nm + 120 degrees so it might be the safest way to go I guess.

Think I might just go with they're instructions so I don't go screwing things up.

Maybe I'll just scribe a mark on the socket to see where I'm up to, rather than marking the bolt and then having to take the socket off to see where I am, and then having to turn it a third time to finish it off.

Thanks for the help guys.

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I'm with Revhead, done thousands of the suckers, if you've got the degree wheel to use with the breaker bar do it that way, plenty of assembly lube on the underside of the headbolts and some on the threads.  And I always use a genuine AU headgasket (steel) never have to do it again.  I've found that the composite gaskets don't last well. 

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i prefer steps like the 40-80-110nm thing. the whole 120 degree thing i feel makes it complicated. and did i exactly get that bolt to 120 degrees. or was it 115 as i try to swing the torque thing around 120 degrees and try to keep the wheel gauge thing in the same spot as you walk around the front of a falcon trying to swing your torque wrench in 1 go if you get what i mean. the hole step by step 40-80-110 stuff etc just seems easier and less harder to stuff up.
i reckon the dial degree thing is better for when the engines are out of the cars
so you can get direct sight over the top of the dial

though i like to make sure i measure it the way how they say in the instructions. that way if something stuffs up you know you done it to the right instructions. so there for you feel less shit if it gos wrong haha.
if the instructions say 40nm + 90 degrees then im doing that
if it gives me a choice of the step to step torque settings. and then the instructions for it then degrees
id probably chose the 40-80-110 thing

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If no-one has mentioned it already, get one of these chaps for $25-$30. Makes getting angular torque simpler and more repeatable. I've done a few E-series heads and guesstimated what 90° looks like with an ordinary protractor and things have worked out fine though.

 

08085_2.jpg

 

One of these guys will eliminate the guesswork and get the job done properly. Whilst I'm not looking forward to my next scheduled head gasket change....I'm looking forward to using one of these..

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Thanks guys, some great info there.

I was looking for one of those Angular Torque Gauges at the local auto shops, but had no such luck there. So I might just grab the scribe and protractor and mark my 120 degree markings that way, as I don't want to wait for another week to get one sent from eBay (the joys of living in rural areas).

As I stated, I'm using a brand new ProTorque TTY headbolts set with a Permaseal Multi Layer Steel (MLS) headgasket, the info sheet that comes with the gasket says 30Nm + 120 degrees, so I'll use their settings as I'm sure I've seen other MLS gaskets come with those exact same directions.

I just liked the idea of doing the 3 stage torque method as I have a good quality Torque wrench, but no angle gauge.

But if you experienced fellas say to use the torque + degree method, that's the way I'll go about it.

That's the info I was looking for, so thanks heaps for the helpful responses.

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