question for anyone who has ever upped their compression ratio

[digger]

woah! now stuff is flying at me! i'll try to keep up...

digger: i just read up on DCR and SCR and i think i've got the basic concept. i am assuming that increasing CR (whether static or dynamic) means shrinking the size of the combustion chamber? and is there a way to compute DCR without having to actually line up the cam, valve and piston on the engine and simulate it? please note that i'm not going for a stroker kit.

Wanganstyle: how do you fit both fans? any pics i can see? also, i do have an oil cooler as standard, but i was thinking maybe there's an upgrade for this? and thanks for the tip on the oil. i'll look around for that locally.

thanks guys!

increasing the CR involves a smaller combustion chamber volume or larger engine swept volume (boring or stroking).

You can't really measure the DCR it is a calulation but there are some formulas available to estimate the cranking compression. You need the bore, stroke, rod length, static CR, inlet cam closing timing and find an online calulator. Essentially what it does is give the effective stroke from when the intake valve closes (because the inlet valve does not close at BDC). Then you use that effective stroke to work out the effective engine size and calcuate the CR as you normally would but using the effective swept volume instead of the actual swept volume.

It is always good to note that DCR is used as a guide for what kind of fuel you will need but the real cylinder pressures vary from what the static and dynamic CR tell you so it is not the be all and end all.