731 replies to this topic

[evo-gsr]

Rob...was reading something yesterday about retourqing head studs after a certain amount of kilometers. Dumb question maybe,  but did you do this at all? I only ask as I have just done a forged rebuild on mine and wondered if its something I should be doing / worried about  also??

[Evo-00x]

Jamo, its the fearful thing that nobody wants to do after fitting a brand new headgasket, but ultimately it makes perfect sense to check that none of the nuts have loosened up after the first heat cycle. It would be negligent not to check! Technically you really shouldn't have to re-torque them and 9/10 times you probably never need to again, but hey, shit can and does happen sometimes for a variety of reasons.

 

Your responsibility begins before fitting the headgasket to ensure that your block deck and head surfaces are straight and fit for use. I use brake parts cleaner in the headtstud thread holes and blow compressed air in to remove any debris, water/oil residue. It also helps to dry out the insides of the threads before you fit the new headstuds in. Although I know manufacturers state 'finger - hand tight', I like to give it a tiny little 'nick' with an allen key as some people's idea of hand tight is different to others   I then grab a steel ruler and rest it on top of 3 or more headstuds at a time to check that they have all installed at the same height. Finish off with cleaning the block and head surfaces with brake cleaner again to remove any oil residue.

 

Always use the washers, nuts and moly lube that come with the headstud as that is what the manufacturer has based their recommended torque setting on. Use the lube liberally. It might seem that you didn't get enough lube with the studs but you'll find you'll still have some left at the end lol. Install to the correct torque sequence in steps (low to high) as advised by the head stud manufacturer as it's VERY IMPORTANT to stretch the bolts on with even clamping force to the headgasket. When you've step torqued to the final torque setting don't assume that you've finished. Let it sit there for a couple hours or so then come back and check the final torque again.

 

When you first put your rocker cover on, don't use any sealant at all. Just bolt it on as normal. Put timing belt on, oil in the engine etc. Run the car to normal operating temps, then switch it off. Let the engine cool COMPLETELY STONE COLD, then remove the rocker cover and check the torque on the headstud nuts. You will find that the torque wrench will click before the nut cracks nearly every time. But if you do get a 'snap' and the nut tightens up that little bit more before the torque wrench clicks, then yeah, that's a slight problem and you will need to re-torque the nuts again.  By re-torqueing them I don't mean loosening them all up and starting from scratch as that will ruin your MLS headgasket. I mean just loosening one nut a little bit (about 1/4-1/2 turn), then tightening it back up to the highest torque setting. Then make your way onto the next nut (in the correct torque sequence).

 

Different people will tell you different things but at the end of the day even ARP recommend re-torqueing after a few heat cycles. I don't really like the idea of doing it on an MLS but I haven't had an issue with mine needing re-torqueing after a 2nd check post installation. However, after I had pushed coolant on the dyno I checked the torque setting and yes, a couple of nuts at 3 and 4 snapped and tightened up a smidgeon more. This says to me that the headbolts stretched and is more than likely to be the cause of my headgasket failure.

 

If it happens again in the same spot with the new setup then I'm going to have to get the head checked out professionally for warping and go from here.

[evo-gsr]

I didn't put mine together.  The engine builder did. So hopefully they would know all of the above.

So now that Ive done 1200 odd k's should I check stuff out??

[Evo-00x]

For sure mate. If you know what headstuds he used find out the recommended torque setting and give it a sanity check at stone cold engine temp.

Best to check now after engine run has completed and before you start to throw more boost into it.

[Evo-00x]

Woohoo. After the headgasket & headstud upgrade, I finally cranked it over today and the water system doesn't pressurise like before.

Will have to take it out for a drive over the long weekend to see how it likes BOOOOOOST and whether it needs to go back to finish the tuning    

Cold start is still a bitch so that'll need attention at least lol

[ENGINR]

Niiice.

 

When do our straight cut gears get here!?

[evo-gsr]

Good stuff Rob. Bet you cant wait to drive it again.

[Evo-00x]

Cheers boys.

Shayne, they still haven't arrived yet and I'm getting nervous. Matthias posted them with DHL Germany on 18th December but they didn't leave Germany until 12th January. 

DHL Tracking states the next step is for the package to arrive in Australia. Matthias chased them up and DHL have/are apparently handing it over to AustPost for delivery. They supplied an AustPost tracking number but its not working on the AustPost tracking system yet. So I can only assume that its still in transit until AustPost log it as being received and commence tracking on this end.

This is the last entry for tracking on DHL's website:

 

Sun, 12.01.2014 09:29 h IPZ-Ffm, Germany The shipment will be transported to the destination country and, from there, handed over to the delivery organization. (Homepage / online shipment tracking: http://auspost.com.au/track/)

 

 

[ENGINR]

Yeah, I saw that too - am starting to get a bit nervous as well!  Not only do I have the $$$ tied up in the parts, but I've got a gearbox in bits that's useless without them!

[jack be nimble]

Auspost tracking is crap. You will get it before it even updates

[Matthias]

dont worry mate, think in a pair of days you have the gears, when the paket is lost we find a solution,I will not let you sit on it

[Evo-00x]

Shayne's in China right now anyway. He's looking for a sweatshop to sew the new 2015 Commodore interior trim lol

[ENGINR]

Hey matthias, please don't think i'm doubting you, i just don't trust courier companies all that much! I've worked in a big enough industry for too long and have lost a few things to "the void" once they have been shipped over the years.

Yes Rob, i'm over here sourcing sweatshops in China!

[Matthias]

Yes.I Know bro ;-)

[Evo-00x]

Good news. Package arrived today and yeah, the fkn AustPost tracking number is correct as its the same as the tracking number sticker on the package, but its not even being logged on AustPost website nor state that it has been delivered today  .

Anyhow its a sigh of relief that we finally got the parts in and now Shayne can rebuild his gearbox   

PS: Shayne, I only unwrapped and took pics of my parts. Im not unwrapping or touching yours lol.. I'll just repack your bits into a smaller sturdier box and post it to you. Just PM me everything I need to know mate.

 

Here's pics of just my 4th dog gear upgrade and having the centre diff housing machined a couple of mm to clear the 4th dog teeth.

Don't worry about the look of the old synchros lol, they are just an old set I sent to Matthias to help with lining up and modifying the 4th gear.

Now I just need to debur and polish the shaft and find someone who can machine this centre diff housing for a 4-spider cross-shaft and machine the cover for a Torrington bearing upgrade like what's in the other gearbox (otherwise I'll have to weld the centre).

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Edited by EVO-00X, 23 January 2014 - 08:27 AM.

[Cranked]

Hella jealous

[Matthias]

at the same day i have send two sets to newzeeland,that gears was delivered before 2 weeks.

but now everything is going well.

Hope that gears make you happy ;-)

until now have breake the 4th after the upgrate,and here are a lot of high power cars with that gears...

[Evo-00x]

Nice. Good to know no one has broken 4th gear yet. That was always my worry on the dyno or under load in 4th

Thanks again Matthias. I think you might get a few more customers out of this lol

[ENGINR]

^{WHOO HOO!}

^{I'm leaving China tomorrow, will be back in Oz Sunday arvo, let me get sorted and I'll fix you up with coin and details on Monday Rob.  I think I still owe you some $$ from earlier so add that to the delivery cost to get it to Melb.}

 

^{Thanks Matthias - I cannot wait to see the gears and get the gearbox rebuild happening.}

Edited by ENGINR, 24 January 2014 - 01:53 AM.

[Evo-00x]

I noticed the 4th dog gear ratio is 23 intermediate and 20 on the 4th gear = 0.869

OEM Evo II/III is 29/25 = 0.862.

That's damn close enough by me