lowering comp ratio

[13bsigma]

hi guys. jets engine is a 2.6L with a copper head gasket in it. .

how else can i lower compression with out changing the pistons? i will be using the same 2.6L forgies in there. can i re use the copper head gasket? i have heard that you can. . i head somewhere you can put 2 head gaskets on each side if the copper gasket and that will work. . is this true? shall i re use the copper one or go about lowering comp another way??

cheers

[Superscan811]

how else can i lower compression with out changing the pistons?

Grab a die grinder and remove all the sharp edges in the combustion chamber.
After that, start blending all the surfaces around the valves.

This will help 3 ways.
1. It will remove "hot spots" which cause detonation.
2. It will increase the cc of the combustion chamber because of the aluminium you remove.
3. It will "de-shroud" the valves, allowing more air to enter and exit the cylinder.

Cheers.

[13bsigma]

ok, so for someone with zero experience with this, maby i shouldn't attempt it without someone beside me who knows what they are doing??? i dont know if i'd feel to confident doing that. . a head reconditioner place would do it right??

thanks for the idea, sounds like a winner to me. more air flow, reduce hot spots, lowers comp. .

[Superscan811]

I started doing one of mine a while ago along with a bit of port re-shaping.

It's not overly difficult but it is time consuming to do it right.

BEFORE




AFTER


As you can see, all the sharp edges have been removed and the area around the valves have been opened up a bit.
There is still a lot of work to do, but you get the general idea.

Cheers.

[13bsigma]

ah yes, i see. so the bit behind the valve obviously wouldn't change the comp at all, but it would improve air flow. . and i see where you removed the bit around the valve too gives me a good idea wher eto start

much appreciated