Built or not, that has nothing to do with it, it sounds like you're running too lean causing your motor to blow.
You need to get a real engine management system, like MAP ECU or AEM. Maybe one of these:
http://www.protegegarage.com/product_info.php?cPath=21_31_49&products_id=1501
well im moving towards las vegas.. so im sure there is some where that can do it... and DAMN YOU... you have convinced me to spend time on my mazda again.... ( thanks... lol ) really though.. haltech shouldnt be tohard to install... i guess it is picking a version that works for me.. i would LOVE to get rid of this horid maf... it would make intake routing and what not so much easier...