Variable compression


Senior Member
Read around, i heard saab was testing someting like that. I have a picture in my head of a cylender head hinged to the block kinda like a jar.

But i think they have something that slides in and out of the combustion chamber to take up space.

not really shure but its a neat thing to contemplate.


Super Moderator
I thought it was Volvo. Saw a little thing on the show motorweek. It has basicly hydrolic hinges that make the engine shift positions and keep the head stationary or something like that. Read up on it. Really, its way in the future. With engines, really, other then sensors, little bit of computer work, messing around with placements, the engines basic operation remains the same, very mechanical. When you start to have the engine constantly moving, your asking for parts to not work. Bugs have to be worked out otherwise your going to have problems like what GM did back in the 70's when they tried to reintroduce the electric vechicle with little real world testing. It fell on its face. Could only go 30 miles or so, toped out at like 50 or so, and weighed close to 2x that of a normal car, although it was half its size.


Senior Member
thats good for saab. I dont see them entering any kind of performance challenges like almost every other car company does. you see fords and chevys in nascar, hondas in everything except nascar, subarus in rallys, etc..
saabs arn't performance cars. obviosly if they had something good like this variable compression, every other car company in the world would be stealing their idea. Honda started VTEC, now you have ZETEC, VVTI, and every other company comming out with variable timing/lift control. Although none are as good as VTEC.