Yes realy. Thats why they have 13-14degree more exhaust duration compared to intake.
And yes they are also made to build cylinderpreasure on low compression engines.
Trebor75: If im not misstaken you live somewhere around Stockholm? There are a few machineshops around town and they may be different on the pricing and how quick work they do,let me know if you have a use for a few names regading machineshops,in case i know some place that you had forgot about:)
