i've just bought some street-porting templates from mazdatrix.before starting to experiment with the 13b engine i bought for my 1st gen,i want to be sure for some details about porting.
for intake street-port,do i have to make both the primary(intermediate housing) and secondary(side housings) ports the same size?is there any option to also resize the external side of the ports(of course the manifold too)?
what should be the estimated horsepower for a street-ported 13b(ex-turbo,with low comp.rotors) with the stock throttle body,injectors,haltech ecu and rb exhaust?

 

I wouldn't do anything as far as enlarging the intake runners in the manifold or in the engine.

 

All ports need to match exactly. Leave the ports on the outside of the motor alone, unless you have a LOT of experince with it.. also leave the intake runners alone

Now make absouletely sure, you dont grind ANY AT ALL towards the E shaft, if you do you have a worthless junk motor

 

Recent Thread with Pictures of Mazdatrix porting

Dozens of pictures and Links to porting

BTW, I noticed that second one is now Archived -
GOOD JOB MODS!

 

Mike P28: I am not sure what you meant by "all ports need to match exactly" . Thats not true at all. What he meant was can he do the primarys one size and the secondarys larger than the primarys. And yes you can, thats what most people do. You need to be kinda careful as to how big the difference between the two is or the transition from primay to secondary will not be that smooth. As far as porting the out side of the motor. Put a piece of paper on the intake manifold and trace that and then match it up to the motor and see if they are identical. if not then port it to match the manifoldso there is no ruff edge there.

CJG