Reducing compression

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Sep 23, 2003 | 07:37 PM

JeffinMd

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Reducing compression

I must be missing something. I've heard people
talk about "spacers" betwen the head and block to reduce the c/r (I'm not saying this is a good idea).
However, I've never seen anyone talking about moving the opposite direction.
Is there room to shorten the piston connecting arms to increase the combustion volume as well? Is there a simple reason why this is a really bad idea?

Thanks, Jeff.

Sep 23, 2003 | 08:33 PM

Audi2ptzero

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If you shorten the rod, the piston top is not going to reach the top of the block.

Sep 23, 2003 | 11:39 PM

Lucas_Gchips

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Re: Reducing compression

You can also fly-cut pistons tops to reduce compression.

Sep 24, 2003 | 04:16 AM

WYSIWYG

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*homer simpson voice* in theory, you can raise the sparkplugs... in theory

just kidding

Sep 24, 2003 | 06:16 AM

JeffinMd

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Right! But wouldn't that "look" the same as having the spacer above the piston top?

Sep 24, 2003 | 11:35 AM

Toaster29

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Not really...headspacers tend to screw up the carefully designed quench zones designed...

by the factory.

Sep 24, 2003 | 12:53 PM

xr4tic

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Why mess with the rods, when you can just change pistons?

Shorten a rod, and you also make the piston go further down the cylinder, possibly going too far, or hitting the crank.

Plus, these rods would have to be custom made.

It's easier to just have a set of dished pistons made to your specs.