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Head Gasket


Spectre927
12-24-2003, 05:19 PM
If I were to put say... a 2.6/3 mm head gasket onto a 96 GSR, is there an easy way to tell what compression will be changed to? Sorry, but I was hoping maybe somone has already done it and knows. Thanks :cwm27:

I found this http://falconperformance.sundog.net/compcalculator.asp

And this....
7) CR = COMPRESSION RATIO = CYL. VOLUME @ BDC ÷ CYLINDER VOLUME @ TDC = 1 + (SWEPT VOLUME ÷ VOL @ TDC)
= 1+ (0.7854 x BORE x BORE x STROKE) ÷ (CCV + HGV + PDV)
CCV = Combustion Chamber Volume, in cubic inches
Note: if volume is given in cc’s then ÷ 16.4 to get cubic inches.
HGV = Head Gasket Volume, in cubic inches,
= Head gasket compressed thickness x 0.7854 x bore x bore
PDV = (Piston Deck Volume) + (Piston Dome Effective Volume)
= (0.7854 x bore x bore x deck to piston distance) + (volume of piston depressions - volume of piston
bumps) Example: What is CR of the engine in #6 above, if heads have 64 cc chamber, head gasket is compressed
to 0.040 inch and flat top pistons give 0.025 deck clearance at TDC? CCV = 64 ÷ 16.4 = 3.90 cubic inches
HGV = 0.040 x 0.7854 x 4.030 x 4.030 = 0.51 c.i.
PDV = 0.025 x 0.7854 x 4.030 x 4.030+ 0- 0 = 0.32 c.i.
CR = 1+ (0.7854 x 4.030 x 4.030 x 3.48) ÷ (3.90 + 0.51+ 0.32) = 1+ (44.39 ÷ 4.73) = 10.38 CR

Spectre927
12-25-2003, 12:48 PM
Never mind you A-holes. I figured it out. It'll make me car a little more turbo friendly.... aaaarrrreeee...

Ricochet
12-25-2003, 12:54 PM
Too many numbas for our wittle bwains to handle lol
So you're saying it will lower the compression right, since it'll be more turbo friendly..

maxspeedhonda
12-25-2003, 05:47 PM
Well what did you come up with? Inline-pro claims that their 3mm HG will lower the CR one whole full point.

Spectre927
12-26-2003, 12:34 AM
I understand :thumbsup:
I just used this... http://www.c-speedracing.com/howto/compcalc/compcalc.php

It says it'll lower it over 1.6 points, but... maybe it'll get compressed once its put on and used for awhile so it won't be a full 3 mm, and perhaps maybe thats how inline got theirs. Anyways, since it should increase the chamber it'll lower it a decent amount, correct? whether it'll be as much as this site claims, Im not sure.

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