What's the thickest head gasket? 3mm?

[paul0075]

but he doesnt wanna pull the block...

how long did you drive on a BHG???

Only 2 block?
When the head gasket was pulled, it wasn't in horrible shape!!
But Cylinder # 6 had a leak in it..
See the car steamed a little and temp went close to H mark while driving, so I stopped immediately, filled with antifreeze drove for 2 blocks, and never drove after that..

 

[Rennat]

wow... your one of the smart ones. your bottom end should be pretty good then. just drain the oil, fill with some generic supertech 5-30, run that for 5 or 10 miles, then change it out for the good stuff. that way if anything shows up in the oil after you do the BHG you wont be wasting 40-50 on high quality synthetic oil.

stock head gasket is 1.37... and your head is at 115mm... so that would make you have a 2.37 HG... but a 2.0MM would do just fine, and if your have the extra money get the HKS STOPPER... other wise just get a titan headgasket if you dont have super high intentions for this car...

 

[EdT.Mk3]

Just going to toss some extra info about the HKS HGs that Supracentral had in his sig since that came up: HKS HG FAQ

 

[IJ.]

The block has been cleaned and checked...
What I am really asking is, what size gasket should I get?
My head measures 115mm. is that stock? or 116mm?
Someone mentioned that the stock head is 116mm.
Also, is the stock head gasket is 1.2mm?
I was going to get the 3mm= 1mm (116-115=1mm) + 1.37mm (hg)
I'm really confused with what the actual head spec (size) is.
Anyone knows?

Stock head is 116mm

 

[paul0075]

Just going to toss some extra info about the HKS HGs that Supracentral had in his sig since that came up: HKS HG FAQ

Thanks, I am going with the stopper, I did my homework on the differences

 

[paul0075]

wow... your one of the smart ones. your bottom end should be pretty good then. just drain the oil, fill with some generic supertech 5-30, run that for 5 or 10 miles, then change it out for the good stuff. that way if anything shows up in the oil after you do the BHG you wont be wasting 40-50 on high quality synthetic oil.

stock head gasket is 1.37... and your head is at 115mm... so that would make you have a 2.37 HG... but a 2.0MM would do just fine, and if your have the extra money get the HKS STOPPER... other wise just get a titan headgasket if you dont have super high intentions for this car...

Thank you so much Rennat...
That was the answer I was dying for...
All I wanted to know is the exact measurements and what size gasket is recommended..
Well, this isn't my 1st Supra, its actually my 4th, I own 2 as we speak, 1 is 89 NA, and this one 90 Turbo. This is my 1st turbo of all of them.
Thank you guys for all your help (and patience)
I'm going to order 2mm STOPPER!
Wish me luck.
Regards,
PAUL

 

[paul0075]

stock head gasket is 1.37... and your head is at 115mm... so that would make you have a 2.37 HG... but a 2.0MM would do just fine, and if your have the extra money get the HKS STOPPER... other wise just get a titan headgasket if you dont have super high intentions for this car...

Should I be worry about detonation if I go 2mm?

 

[IJ.]

You should ALWAYS worry about detonation no matter what the combo, finding the gentle rattle threshold is all part of a good tune.

 

[paul0075]

You should ALWAYS worry about detonation no matter what the combo, finding the gentle rattle threshold is all part of a good tune.

Well, I guess what I meant to say is that if I get the 2mm gasket, will it now be closer (valves to pistons)? Or I'm wrong..
Since the gasket size I will really need is 2.37mm (according to specs), but I'm getting the 2mm.

 

[IJ.]

Ummm it'll be .37mm closer to the valves..... (about 14 thou)

 

[CRE]

Hey bud, you're cutting corners and you're most likely going to pay for it. The straightness of the block is NOT the only factor in a MHG sealing well. The roughness of the block is the other MAJOR factor. There's texture there from the factory. From the factory the block never had a finish that would seal well with a MHG. If I had to guess I'd say that 80% of the people who post about blowing a HKS MHG blew it because they ignored the block.

If you insist on ignoring the block I'd go with a cometic.... general consensus is that they're the most forgiving.

If there's ANY pitting of the block's deck... forget it.

 

[paul0075]

Ummm it'll be .37mm closer to the valves..... (about 14 thou)

Is that really bad or its OK,
Reason I'm asking, is the fact I'm one button away from buying the HKS 2mm Stopper!! Or should I go 3mm?
Thanks

 

[IJ.]

Just trying to make YOU think Paul and not spoon feed you

Stopper is VERY fussy about surface flatness and finish it may not be your besy option.

 

[paul0075]

Just trying to make YOU think Paul and not spoon feed you

Stopper is VERY fussy about surface flatness and finish it may not be your besy option.

Well, maybe I will go with the bead then since I haven't resurfaced the block.... Just thought it might be better to go with Stopper since its only $95 more than the bead type
I'm not looking for high power and upping the boost.. just want a reliable engine at stock level..
My questions is though, will the 2mm be too thin? or just enough to do the job?
Oh also, Is the 86mm bore OK? I didn't hone the block.
Thanks

 

[Rennat]

people shave the block and head and then slap on a 1.2mm and there fine...

i went with a 3mm... and wish i had gone with a 2mm.

and if your worried about the sealing surface, then get the cometic, as there MUCH more forgiving.

 

[paul0075]

people shave the block and head and then slap on a 1.2mm and there fine...

i went with a 3mm... and wish i had gone with a 2mm.

and if your worried about the sealing surface, then get the cometic, as there MUCH more forgiving.

I heard good reviews about the Cometic gaskets, but wasn't sure if they are good for my application.
I really appreciate your replies guys... I own a MINT supra and want to keep it this way and make sure its in great running order...
I like to buy only the good stuff. That's why you see me asking all these questions.:dunno:

 

[CRE]

That's why you see me asking all these questions.:dunno:

And yet you're still not really listening to all the answers.

And "BEST" is entirely subjective. A HKS Stopper, for example, is probably the WORST for your build... won't know until it blows of course.

 

[paul0075]

And yet you're still not really listening to all the answers.

And "BEST" is entirely subjective. A HKS Stopper, for example, is probably the WORST for your build... won't know until it blows of course.

LOL... Bear with me, this is my 1st re-build..
It's not that I'm not listening, it's the fact that there are a lot of people here on this forum that did their rebuilds and each one had different applications and different results... Some succeeded and some failed miserably. I just want to be on the safe side...

I owned a Supra since 1995, it was 87 NA overheated after it hit 213k miles, after that I owned 2 other Supra's both 89 NA's.. I know a great deal about the car and its components.. But this is my 1st Turbo car and I want to do things right (THE 1st TIME).:wiggle::x:

 

[CRE]

LOL... Bear with me, this is my 1st re-build..

Oh fine... <mechanical voice> Rant mode: DISENGAGED</mechanical voice> :biglaugh:

 

[Rennat]

if your not going to machine the block, get a cometic. because the HKS probably wont seal. it has to have a 30RA (how rough the surface is) or less. the cometic is 50RA...

did you do a compression or a leakdown test before you tore it apart to check the condition of the rings though? i would hate for you to go through all of this trouble, and then have a few cylinders that have low compression....