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924 NA Head Gasket Crushed Height

 
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joewest  



Joined: 06 Oct 2005
Posts: 234
Location: Portland, OR

PostPosted: Thu Dec 20, 2018 7:42 am    Post subject: 924 NA Head Gasket Crushed Height Reply with quote

Hey Gents,

Does anyone have the dimension of the crushed thickness of the stock sized Victor-Reinz composite head gasket?

I am doing displacement calcs on my engine as I prepare to add an M62 and am considering not using the Cometic sitting on my shelf that crushes down to .051" due to the state of the block's deck surface roughness and high estimated CR.

Thanks!
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safe  



Joined: 18 Mar 2017
Posts: 592
Location: Sweden

PostPosted: Thu Dec 20, 2018 6:14 pm    Post subject: Reply with quote

I'm in the thought process of something similar.

I have no clue about the crushed height, but the stock gasket is 1.7 mm and according to some calculations I did a 1 mm of change adds/removes about 0.7 to the compression.

If it compresses a couple of tenths or not it doesn't really affect the compression that much...
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poor-sche  



Joined: 06 Jan 2017
Posts: 80
Location: Los Angeles, CA

PostPosted: Fri Dec 21, 2018 4:12 am    Post subject: Reply with quote

See if this helps...

http://garage.ideola.com/top-DL-CompressionRatioCalc.html

It's a link to a compression ratio calculator on Ideola's old site that still works; well at least for now.
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joewest  



Joined: 06 Oct 2005
Posts: 234
Location: Portland, OR

PostPosted: Fri Dec 21, 2018 4:43 am    Post subject: Reply with quote

poor-sche wrote:
See if this helps...

http://garage.ideola.com/top-DL-CompressionRatioCalc.html

It's a link to a compression ratio calculator on Ideola's old site that still works; well at least for now.


It defaults to .046", but that is not proof enough that this is correct. I have a spare gasket that I am going to install, torque down with the head and then remove and measure. If I was not so hasty in throwing out the old one I removed I would have had my answer. But alas....

I am keeping a photo journal of the build here if there is interest...

https://photos.app.goo.gl/Mua2zeV8zLs5DUgE9
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safe  



Joined: 18 Mar 2017
Posts: 592
Location: Sweden

PostPosted: Fri Dec 21, 2018 5:10 am    Post subject: Reply with quote

joewest wrote:


I am keeping a photo journal of the build here if there is interest...

https://photos.app.goo.gl/Mua2zeV8zLs5DUgE9


Yes!

What throttle body are you using?
I'm looking for something bigger (than stock) and can accommodate a TPS. Preferably bolt on or easy to make an adaptor.
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joewest  



Joined: 06 Oct 2005
Posts: 234
Location: Portland, OR

PostPosted: Fri Dec 21, 2018 5:28 am    Post subject: Reply with quote

I am using a Weber/Redline 60mm assembly. It was a direct bolt-on with no mods to the intake manifold. Also, the inlet accommodates a 3" diameter ROUND hose which is readily available.
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MikeJinCO  



Joined: 08 Jun 2010
Posts: 1229
Location: Maysville, Colorado

PostPosted: Fri Dec 21, 2018 11:45 pm    Post subject: Reply with quote

My actual figures are at home and I'm in Mexico, but as I recall I found quite a bit of variation across the crushed head gasket but if i recall correctly the thickness was in the range of .056 to .062 and I used about .060 for the average. Hope this helps.
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safe  



Joined: 18 Mar 2017
Posts: 592
Location: Sweden

PostPosted: Fri Dec 21, 2018 11:59 pm    Post subject: Reply with quote

MikeJinCO wrote:
My actual figures are at home and I'm in Mexico, but as I recall I found quite a bit of variation across the crushed head gasket but if i recall correctly the thickness was in the range of .056 to .062 and I used about .060 for the average. Hope this helps.


And the difference between "under crush" and "post crush" ?
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joewest  



Joined: 06 Oct 2005
Posts: 234
Location: Portland, OR

PostPosted: Sat Dec 22, 2018 3:15 am    Post subject: Reply with quote

Thanks for the feedback gents.

I installed a gasket, torqued it down and then took the head off and measured the gasket again (at the fire rings, each cylinder bore, each quadrant). Cold motor, reused factory bolts, dry, torqued to specs.

Part Description: Victor-Reinz 93110433706 Head Gasket

Out of the box:
Height = 2.0mm (0.078")
Bore Diameter = 89.2mm (3.512")

Installed and Removed:
Height = 1.98mm (0.078")
Bore Diameter = 89.2mm (3.512")

These tolerances are beyond my concern with this build, so I am using 2mm, with a bore of 89.2mm yielding 12.5cc static per cylinder. That delta in height is only about 0.1cc which is not a concern for me.
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joewest  



Joined: 06 Oct 2005
Posts: 234
Location: Portland, OR

PostPosted: Sat Dec 22, 2018 4:41 am    Post subject: Reply with quote

There is a Weber/Redline TB on ebay now....

https://www.ebay.com/itm/60cfl-Performance-Weber-Throttle-Body-Redline-VW-Type-3-4-Volkswagen-Manifold/283272310411?epid=21026189687&hash=item41f4586e8b:g:ufYAAOSwQZdb9LhH:rk:1:pf:1&frcectupt=true
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