| This page will take shape over the next few weeks as I add the pix and text to show the progress on my 2001 PT limited with a Hahn turbo system. |
| The head I am using has been ported to near maximun safe size, using 1mm oversize valves made from stainless steel for turbo use. |
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| The sides of each valve seat has been cut with a radius form tool to provide the exact same diamiter relief around the valves to maximize and equalize the breathing of all the valves. This 15 dergee radius cut blends into a 30 degree top cut, down to the 45 degree seat angle, down to a 60 degree throat cut, to a 75 degree lower cut. |
| The ports are matched to the SRT-4 intake gasket, as is the intake manifold. The aluminum lower half can be ported like this |
| Page 2 |