A tip for removing the rollpins securing these sleeves - use a thread tap in the hole of the pin. I used a 3mm tap directly in the hole (I broke my 6-32 tap, but maybe I should have cleaned the hole with a 7/64 drill first).

Clean the pin & give it a shot of WD40. Thread in a 12mm machine screw. Take a pair of side-cutters, grip under the head and lever the pin up (pushing or hammering down on the handles). Protect the housing surface you're bearing against with a scrap of metal or wood.



A question now I've got them out - this motor is getting a street port on the intake side. How much should I do on the exhaust side? Should I remove all of the diffuser vanes? Will it get a little, or a lot louder? Should I just grind out the center 'bump' of the diffuser, as it seems to be the bigest obstruction? Should I square up the radiused corners of the port a bit?

I have a header, hollow cat 'resonator', and a Trust 2 1/4" cat back exhaust. Not looking for 'max' power, but don't want to leave it on the table while the engine's apart either.



Thanks any and all,

 

Yes it will get a "little" louder but not by much. I swapped my na sleeves for some TII sleeves when I did my rebuild and street port (S4 NA). I also ground my exhaust port down a couple millimeters on the opening side but didn't mess with closing timing or port width. I ground the port so that it would flow smoothly into the sleeves. I kept the round exhaust port shape and didn't square it. I also did a medium / large street port (medium primary and secondary with large aux) and it runs fine. Opening up the exhaust port should create more top end power with less low end torque. I ported my engine for a pretty level torque curve so I could autocross the car, but if you want more of a drag race machine, you could open up the exhaust port a little more than I did.

 

Thanks alot for the advice. Those little wings are outta there now!



I'll do the same with matching the housing to the sleeve edges. Intake will be along the lines of the Mazdatrix streetport.