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Old 04-22-2002, 01:54 AM   #1
G-REX
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Question Head spacer?

Going with a thicker head gasket effectively drops the compression in the cylinders. Not by much though.

So has anyone fabricated a custom "spacer" that goes between the head and the block? It would use two gaskets; one between the head and spacer, and between the spacer and block.

Does something like this exist already?

I'm thinking a metal plate about 1/2 inch thick and takes the shape of a gasket. What could be the compression drop from say 10:1? Speculation welcome.

Also, what would you think the problems with this would be? I would think probably the bolts would be too short, and maybe there would be a clearance issue since the heads are further from the block, but that's really it.

EDIT: Hmm, just thought about something. The exhaust might not line up correctly, and maybe the fuel rails.
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Old 04-22-2002, 02:25 AM   #2
Andrew
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if you want to lower the CR, this isnt the proper way. do it by changing out the pistons.
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Old 04-22-2002, 02:35 AM   #3
KillerTHC
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this will drop it to what? 9.9:1?
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Old 04-22-2002, 03:28 AM   #4
HndaTch627
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actually MR gasket just released a new series of head gaskets w/ spacers...my boss has one and we'll see how it works...as you all well damn know i DON'T trust gaskets to lower CR in high performance applications...but i do know that the MR gasket piece lowers compression from 9.6:1 all the way down to 8.2:1 at it's thickest setting...pretty unreal...we'll have to see how it works...the next concern would be the lack of length in the timing belt to take advantage of this.

jeremy

edit: i can type 90WPM....but no one said i had to spell at the same time.

Last edited by HndaTch627; 04-22-2002 at 12:34 PM.
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Old 04-22-2002, 10:17 AM   #5
AaronB
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As Jeremy stated I would be concerned about the timing belt length and the fact that with our flat engines you can't space the heads out too far before you will need to "modify" the intake manifold and the exhaust manifold to fit.

When I used copper head gaskets that were about 2x's as thick as stock, the intake manifold barely would bolt on without modification. Any more distance and I would of had to enlarge the bolt holes in the manifold.

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Old 04-22-2002, 12:36 PM   #6
HndaTch627
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aaron brought up a point i totally forgot about last night...you have to consider the fact that you will be effectively lengthenging the short block. anyhow...get the pistons...do it right and do it once.

jeremy
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Old 04-22-2002, 01:36 PM   #7
Jewbaru
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I was reading about "Squish" the other day, and by using a larger gasket, you're screwing up the "squish" of an engine. This can lead to problems.
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Old 04-22-2002, 08:38 PM   #8
STiTuner
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if you did this on a boxer motor wouldn't you need a custom header?


Brad
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Old 04-23-2002, 02:49 AM   #9
HndaTch627
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Quote:
Originally posted by STiTuner
if you did this on a boxer motor wouldn't you need a custom header?


Brad
there is a slight amount of space to go......but theoretically yes.

joel-yes it does mess with the "squish" area designed in the piston.

jeremy

Last edited by HndaTch627; 04-23-2002 at 01:03 PM.
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Old 04-23-2002, 11:25 AM   #10
Jewbaru
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Quote:
Originally posted by HndaTch627
andrew-yes it does mess with the "squish" area designed in the piston.

jeremy
Andrew said that? I thought I did.
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Old 04-23-2002, 01:04 PM   #11
HndaTch627
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Quote:
Originally posted by Jewbaru


Andrew said that? I thought I did.
sorry joel i tend to read thru things too quick and not pay attention all the time....changed it....my bad.

jeremy
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Old 04-23-2002, 04:24 PM   #12
Andrew
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you think i would know what squish is jeremy? !!
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Old 04-24-2002, 03:02 AM   #13
HndaTch627
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Quote:
Originally posted by Andrew
you think i would know what squish is jeremy? !!
you've been surprising me lately once again sorry joel
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