Some of us are going through engine rebuilds at the moment, a couple of us at SE. We are having our heads and valves done, so what are the ins and outs of having polished heads and valves etc.

 

I know that the gases can shift through the heads quicker but what sort of power gain should you expect from this upgrade?

 

 

Tim

;-)

 

You will not see a terrific amount of HP gains with just a Polish and port - The Better air flow will be best taken advantage off if you intend to upgrade turbos injectors and cams - it can also help to reduce combustion chamber temps.

 

Depending on the price charged it would think twice about having it done unless it is a) a very good price b) you plan to go very high HP.

 

Hope that helps

 

Z ya

Nico 91TT

 

 

From what I've heard the heads of the TT are already very well designed for maximum flow, so porting the heads won't do that much.

 

The valves however can be grinded and polished....the socalled '5 angle job', which means the flow along the valves will increase significantly.

 

-Eric

 

IMHO this is more of a fine tuning or blueprinting job. Nice to have, good to do if the engine happens to be apart and it's being done at reasonable cost. I guess it all depends on where you want to end up. If you're chasing every last BHP and efficiency is crucial then you will do it. If not then it's not such a big deal.

i agree that it is not a very cost effective measure of gaining horsepower.