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I supported Toymods
Location:
Central Coast
Registered:
May 2002
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Retorquing 7MGTE Head
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Thu, 13 February 2003 15:08
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Hey all,
I was just wondering, can I retorque the head without replacing everything? I have had my car for quite a few months now, given it hell, and no sign of blowing the HG 
But I still worry about it and I would really like to start running a bit more boost soon. Would it be ok to do this, or pretty much be pointless?
TA!
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Location:
Barossa valley SA
Registered:
January 2003
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Re: Retorquing 7MGTE Head
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Fri, 14 February 2003 01:15
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I read somewhere that with a decent head gasget (such as a HKS metal head gasget) you can run something like 20psi with stock internals so that may be something you want to do at the same time anyway!
just a thought 
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I supported Toymods
Location:
Central Coast
Registered:
May 2002
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Re: Retorquing 7MGTE Head
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Fri, 14 February 2003 01:25
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Yeah, I realise this, but what I was hopeing to do is to retorque it qithout having to go to the expense of replacing everything. I'll do that when/if it blows. But I'm sick of waiting I want more boost hehe 
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Location:
Barossa valley SA
Registered:
January 2003
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Re: Retorquing 7MGTE Head
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Fri, 14 February 2003 01:27
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What else might you have to replace apart from the head gasket?
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I supported Toymods
Location:
Central Coast
Registered:
May 2002
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Re: Retorquing 7MGTE Head
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Fri, 14 February 2003 01:30
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Ive healped a friend do his, we did MHG, ARP studs, new gaskets for inlet and exhaust etc, and things like the little rubbers for the injectors etc it all adds up. Spent roughly a grand so far, still not finished yet..
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Location:
c'town, NSW
Registered:
May 2002
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I supported Toymods
Location:
Central Coast
Registered:
May 2002
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Re: Retorquing 7MGTE Head
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Fri, 14 February 2003 01:34
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Excellent, thanks Rob.
Is there anyway to check how tight they are at the moment? Can I use a torque wrench and set it to 72nm? and see if it clicks ? Could this work? I spose the bets way would be to do as you said, undo then redo.
So this isn't going to affect my HG as it is now is it? Undoing it then redoing it up?
Thanks!
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Location:
c'town, NSW
Registered:
May 2002
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Re: Retorquing 7MGTE Head
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Fri, 14 February 2003 01:46
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there is no way to see how tight they are that i know of.
find someone who knows the torque sequence then just undo a bolt, clean it, and torque it up, move onto next bolt in sequence. this wont disturb the HG as much as taking all the bolts out at the same time.
im at work ATM so have not access to my old mans 7M manual if no one can get u the sequence today then ill post it up when i get home.
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Location:
NSW
Registered:
August 2002
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Re: Retorquing 7MGTE Head
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Fri, 14 February 2003 02:42
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I have had 3 off &M BHG's and I have no faith in the retorque after speaking to a lot of people a few years ago.
If you want to do it you should start with the torque wrench at 50ft/lbs then say 58 (OEM torque), then 62, then 68, then 72 max.
Problem is there is a good chance the HG will crack when doing this retorque, also head bolt threads have not been cleaned nor the threads in the block and no lubrication.
Also I have heard that the bolt should be backed off a 1/4 turn before tightening.
Good luck. I'd be changing the HG and bolts. Also considering alternative engine management and a new knock sensor if SupraGTE's experiences are anything to go by. Which I think they are.
Michael
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Location:
Brisbane
Registered:
December 2002
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Re: Retorquing 7MGTE Head
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Fri, 14 February 2003 07:29
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yep they were something like 55lbs from toyota....need to be done up to 72.
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Location:
Brisbane
Registered:
May 2002
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Re: Retorquing 7MGTE Head
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Fri, 14 February 2003 14:36
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When I re torqued mine after my rebuild I made sure there was a small amount of oil under the head bolts so they didn't stick and give a false torque reading, and backed em off 1/2 turn before re-torquing them. As the others said do one at a time in the right order and you will probably be fine. The HG is one of those things that if it ain't broke I wouldn't want to change it .
Cheers
Wilbo
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I supported Toymods
Location:
Central Coast
Registered:
May 2002
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Re: Retorquing 7MGTE Head
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Fri, 14 February 2003 22:55
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Wonder if I should just start playin worth boost levels and then if it does go, which I hope it dont  , then I'll just have to take the MHG road...
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Location:
North Sydney
Registered:
May 2002
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Re: Retorquing 7MGTE Head
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Sat, 15 February 2003 00:02
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No, I advise you re-torque it first. Mine is the factory head gasket just re-torqued and I'm getting 420hp out of it without lifting the head.
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Location:
Brisbane
Registered:
May 2002
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Re: Retorquing 7MGTE Head
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Sat, 15 February 2003 00:36
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Yeah re-torque it first for sure! Changing a HG is not THAT easy, there is a fair bit of stuffing around and cost involved, and if you can avoid that by a preemptive torque why not! My suggestion is to get the right sequence, back them off (one at a time) apply a little oil under the bolts to help with friction and then torque to 52 (do for every bolt), them just torque them to say 60 (do them up in the right order), then 66 and then finally 72.
This is just what I would do (is a lot easier to do this than the whole head gasket! lol)
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also make sure the bolts are clean and when torquing them up you be nice and progressive, if during the tightening the bolt jerks or "cracks" (i cant think of a better term) this can lead to a wrong torque setting, u will have to undo and redo.
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Also good advice.
Cheers
Wilbo
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Location:
Brisbane
Registered:
December 2002
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Re: Retorquing 7MGTE Head
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Sat, 15 February 2003 00:40
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dont forget if you leave the hg and it blows and your car overheats, you could crack the head, warp the head, or even crack the block...which any of the above u may as well throw away the engine.
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I supported Toymods
Location:
Central Coast
Registered:
May 2002
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Re: Retorquing 7MGTE Head
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Sat, 15 February 2003 00:47
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Thanks HEAPS for your help guys. I will definently do it this week sometime. I'll let ya's know how it goes !
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Location:
Perth
Registered:
January 2003
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Re: Retorquing 7MGTE Head
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Sat, 15 February 2003 08:51
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It is important to back the bolts off and lube them before you retorque. I would torque them to 85 ft/lbs. If you do a search at www.supraforums.com you will find HEAPS of info! Good luck
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Location:
NSW
Registered:
August 2002
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Re: Retorquing 7MGTE Head
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Sun, 16 February 2003 22:48
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I thought the upgraded torque was 72 not in the 80's.
Anyway, if your going to back the bolts off, if may be worth buying a tap and running it through the thread to clean it out, then reinstall with the anti-sieze grease.
It is usually recommended is the Supra procedures to tap the thread. I bought one to do the job for $20, but you'll have to ask for a retapping type, they are a little different than normal taps. You'll need a vacuum cleaner with extension to suck the crap out of the hole afterwards.
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