What exactly are Swirl port heads? I think they are heads the have a "slide" behind the intake valve, but I'm not sure. Do our cars have these type of heads? Are they good or bad? Any info you have on them would be appreciated. Thanks

 

Generally speaking, they are not a performance head. They can be used to build a torque monster, thats about all. There is a spiral ramp around the intake valve stem which is used to intruduce a large swirl of the fuel / air mix in to the combustion chamber. This works really well and is very efficient. Unfortunately, this very same ramp, hinders the flow required once the rpms build, thus limiting the effective power band of the cylinder heads.
I have them in my GTA, (temporarily)m, and it pulls extremely hard from idle to 4500 rpm, but the engine is dead from then on up.
They are really designed for truck use, i.e. torque, pulling power.

Hope this is of some help.

Cheers

Richard