>
> I may have some (a lot of) mis-information in my head.  I had assumed
> that the injectors in the block were the secondaries because those
> ports are smaller.  I'm not actually using injectors in that location
> as all of my injectors are in the tubes feeding the ports.  Will I have
> any problems using the smaller ports as secondaries and the larger ones
> as primaries?  Would it be different if I had the injectors in the
> block?
>
> Bob W.
>
>>

No, just the opposite, Bob.  The injectors in the center housing are the primary injectors fed by the two small port openings in the center of the intake manifold (stock).  The secondary runners are larger in diameter than the primary runners in the stock manifold.  This permits the secondary runners to flow more air easier as the demand for air increases as rpm and power goes up.  Generally the primary injectors are on all the time from idle to WOT (one reason they are called primaries) whereas the secondary injectors are normally only on when the demand for more fuel (rpm and power increasing) reaches a certain point.  This is referred to as "Staging" where it goes from 2 injectors (primaries) to 4 injectors (Primary + Secondary) working.  If you are using stock 13B Mazda injectors the engine will run at approx 90 % power on either pair of injectors.

Also the intake port   timing is different (in the stock block), with the primary ports opening sooner than the secondary ports and the secondary ports closing later than the primaries (it varies a bit from one year and model (N/A vs Turbo)).

But, its really not a problem Bob.  All you have to do to make the two center housing intake ports correspond to your primary injectors is to make certain the electrical connectors from the primary injector wires of Tracy's EC2 go to the injectors feeding those ports.  Wait, I guess it could make a difference if the flow rate of your primary injectors and secondary injectors are considerably different.  Mine are the same flow rate - so it doesn't matter.  If your injector flow rates are different then you want the smaller flow injectors feeding the center housing ports and the larger flow injectors feeding your secondary ports.

Your engine would run with either set up - but I would highly recommend setting it up conventionally.

Ed

Ed Anderson
Rv-6A N494BW Rotary Powered
Matthews, NC
eanderson@carolina.rr.com
http://members.cox.net/rogersda/rotary/configs.htm#N494BW
http://www.dmack.net/mazda/index.html