Ready for a new headgasket, questions

[TargaMK3Turbo]

Hey everyone!

So I just got my head back today, I was told the 0.006 was shaved off. The head was also flow tested and gone through.

Here is my problem(s):
The motor was replaced 4 years ago. 1800 miles ago is was freshly rebuilt by an owner who I cannot get ahold of.
I have no records of the head being shaved before.
I blew a bead gasket, when removing the head I could easily loosen the head bolt with a 3/8 drive wrench. My guess is the gasket blew due to improper torquing.

So, I'm buyin through 935 motorsports. I need to get a combo for ARP head studs, a headgasket kit, and a Cometic gasket.

What size gasket should I go with? It's a stock 7M and I plan on doin bolt on's, no major engine mods.

Thanks!

I have to order today so the sooner the replies, the better :icon_bigg

You can also talk to me on AIM BA94pgt
I'll be online till I get an answer, lol

 

[starscream5000]

How much was taken off the head?

Is the block flat and smooth?

 

[TargaMK3Turbo]

How much was taken off the head?

Is the block flat and smooth?

six-thousandth's

no, nothing was taken off the block, but it's flat and smooth. Thats why I'm going with a Cometic and not a MHG.

 

[dugums]

six-thousandth's

no, nothing was taken off the block, but it's flat and smooth. Thats why I'm going with a Cometic and not a MHG.

??? Cometic is a MHG

 

[TargaMK3Turbo]

??? Cometic is a MHG

I was told I can go with a Cometic being my head is shaved and block is not.. I'm confused now...

 

[starscream5000]

How do you know the block is flat and smooth?? You need to edit the amount taken off the head in your first post, you're scarring people who are reading this.

 

[TargaMK3Turbo]

How do you know the block is flat and smooth?? You need to edit the amount taken off the head in your first post, you're scarring people who are reading this.

lol, one 0 short, lol.

A dial indicator was used.

Also, the head was barely tightened down. Whoever rebuilt this thing only did the 1st step in torquing down the head. It didn't blow out the sides, a couple went from cylinder to cylinder. It wasn't bad at all.

 

[starscream5000]

A compressed stock HG is 1.37mm thick. .006" is 0.1524 mm. To keep the stock compression, all you have to do is the simple math .

 

[TargaMK3Turbo]

A compressed stock HG is 1.37mm thick. .006" is 0.1524 mm. To keep the stock compression, all you have to do is the simple math .

Thank you

But thats not my problem. The engine was replaced about 4 years ago. Rebuilt about 1800 miles ago. I have no idea if any of the head was shaved then...
Do I go 0.1524mm or larger?

 

[starscream5000]

2.0mm should leave you safe . But it you really want to know, the stock thickness of the 7M head is 116mm from cam deck the head deck.

 

[TargaMK3Turbo]

2.0mm should leave you safe . But it you really want to know, the stock thickness of the 7M head is 116mm from cam deck the head deck.

Thanks, I'd rather have a lil lower compression and be on the safe side then be too close and things start breaking.

Can I use a Cometic then? If not, what the very best gasket I can use for my application?

 

[dugums]

I was told I can go with a Cometic being my head is shaved and block is not.. I'm confused now...

Cometic is a MHG that, by specification, requires a surface that is not quite as smooth as what other MHG's require.

This doesn't mean it is supposed to be used on an unprepared block. Prep work will still be required to achieve the recommended RA on the block for a Cometic HG.

 

[starscream5000]

All you have to do is measure the thickness of the head to see if there was ever any material taken off of it besides what your mechanic took off.

The very best there is is open to discussion, but most would say the 2.0mm HKS stopper MHG, but you'd be wasting your money on it without pulling the block and taking it and the head back to be smoothed down to and RA of 20 or less...

 

[TargaMK3Turbo]

Ok, so what gasket should I go with?
If I'm gonna do this, I wanna use the best stuff the 1st time.

ARP head studs
Headgasket kit
???? headgasket????

The block is staying how it is. I don't want to use a MHG if it's not going to be the best choise for what stage I'm at now.

startscream5000, do you wanna talk on AIM?

 

[dugums]

Get a Toyota head kit. It will have all of the top-end gaskets (including headgasket). Even valve seals, etc are included.

 

[starscream5000]

I'm at work, sorry.

If you don't want to pull the block, then my suggestion is to stay away from the MHG's as they will be prone to blowing without being absolutely sure the block is flat and smooth enough for your MHG brand's specific RA specs.

 

[TargaMK3Turbo]

Ok, so what gasket?

The valve seals have already been replaced. The head was taken apart, all seals replaced and the valves were lapped as well.

 

[dugums]

Ok, so what gasket?
.

Toyota or Fel-pro

 

[TargaMK3Turbo]

Toyota or Fel-pro

Thats the best one for what I can go with?

Seems shitty to me :icon_conf

The engine is about 4years old from what my record tell me if that matters any...

 

[starscream5000]

Stock with permatex brake quiet or a copper type spray on it then. You'll have higher compression unless you can find a thicker gasket that's a composite...