I just saw the thread about this on the 12a. What is the biggest porting i can use with stock seals? Where can i purchase the templates specifyed? Can i used the stock fuel system with this porting?

GSL-SE motor.

 

big street port. also, you can also use the stock seals on a half-bridge....full bridge is also ok but dont go pass 9K RPM. all of the above is using the 12-A or any old 13-B 4port plates. just convert your existing GSL-SE 6port engine to a 4-port. you will not be disappointed.

with the template....racing beat or mazdatrix.
fuel-fi pressure is high; you can get away by using a 4port f/p regulator which will allow you to have a return line.

 

Full bridge going to only 9k RPMs probably will be alot less effective than a big street port. I don't really understand what a half-bridge is. How do i make it a 4-port engine?

 

You can use everything from the GS-SE engine except for the cast iron plates (front, mid, rear). To convert it to a 4port, you can get the plates off an earlier 12-A engine to larger center port runners.

 

Too much money, i just want to do this as cheaply as possible and get the car runiing again.