nothinguntil

The “6th Port Streetport”:
I have recently developed a special version of SP unique to the 6 port nonturbo engines (84-91 13B). This port allows for a nice top end power increase with absolutely NO decrease in low end pull, driveability, or even emissions testing. This is accomplished by only porting the 5th and 6th intake ports, and a very light exhaust port. The “lower” 4 intake ports, responsible for idle and low rpm driving remain untouched, and so do the normal driving characteristics of the engine. Only at/above 3800rpm, when the auxiliary ports open, does the porting take effect and move more air through. No emissions test that I am aware of, even the dyno/roll test, pushes the engine to the point where the auxiliary ports open, therefore this is a good way to “hide” your performance gains from the emissions test. For those who don’t care about this, I can/do still port all the ports of a 6 port engine. I highly recommend the pineapple racing 6th port sleeves to compliment any streetport on a nonturbo engine.





I am going to get a rebuild done on my N/A 89 rx-7 in california and I think I am going to get it done at Mazda racing. I did a search on porting, california, emissions and didn't find much. I saw the porting of the 6th port posting but still no has said anything thing like, ya I have a ported rotory engine in cali. and I past smog just fine. I"m hopping some one on here can tell me that they have done it and it works before I spend the money on something that someone says can be done but then no one really has it done it? I guess if no one on here has a ported engine that has passed emissions I will just go with the basic rebuild, but thats no fun at all.

RETed

You mean like this...?




-Ted

Rxmfn7

iTrader: (4)

I really dont think a normal steetport would hinder emissions testing very much at all.. Heck Ive heard of people passing with partial BPs...

nothinguntil

so did you pass emissions with that bad *** port ya have there

hypntyz7

Damn Ted, where'd ya get that??

hypntyz7

BTW, Im the author of the above quote. I definitely did not "invent" that style of port, but I find it to be really useful on nonturbo engines where people care about emissions or low end. IF you don't fool much with the exhaust, and you only port the auxiliaries, you will get a power gain but no change in emissions or low end torque. In this case I leave the 4 primary ports alone.

The picture is sort of the same idea of what I do, but obviously a bit cleaner and larger and without the type-R scorch marks in the oil tracks...

nothinguntil

ya I am going to keep my double cat on for my cali emissions. I just needed to feel more confident that it will work so I don't wast 3 grand on my upgrade. Thanks for all the reply guys

RETed

The housing is a "dead" one.
I was just fooling around to see how much cutting it could handle before I start making holes in the water jacket - the 6 port NA housing can take a lot of porting!&nbsp If you look carefully, there's two dents inside the port where I tried to chisel holes to see if it'll break.&nbsp There's still a LOT of metal back there...unlike the turbo ones.

After I seen the Judge Ito ports, I had to try my hands on the NA irons to check it out myself - wow.


-Ted

hypntyz7

Ive done a few ito-spec ports for guys too. It is nice if you want the simplest posible NA engine. No emissions, no 6 port rods or actuators, nothing. Im told (I have yet to drive one of these) that they make killer power over 4500 all the way to the limiter, and that they're loud as hell with an open exhaust