flyrotary@lancaironline.net Mailing List Archive

Turbocharger Hiflows 12A 13B Series IV & V

I agree with Rusty's assessment regarding the stock Mazda 13B turbocharger. The tech papers clearly show the engineers were after lots of boost at the lower rpms for that sports car kick. Even in the car, there has been consistent problems with "overboost" or "boost creep". If you are going to use the stock turbo then you should consider some modifications along the lines of these turbos. I don't necessarily recommend you try this on your ShopMaster mill (you hear, Rusty?) , better to have a professional turbo house do it.

The opening up of the turbine outlet as well as enlarging the wastegate port will move the "boost" regime up the rpm range coming on at 4500-5000 rather than at 1500 rpm. The bigger compressor will has better efficiency as well as less opposition to airflow when not in boost. Just something to consider.

Ed Anderson

12A & 13B Series IV & V

No Modifications Required - Bolts Straight On!
Factory Hybrid HiFi Sleeper!
Looks factory but internally supplies up to a 100% HP Gain at 15 PSI Boost!

	Recondition, blueprint & performance balance to < 1/2 factory spec. your existing HT18 turbocharger.
	Fitted with an ATS modified T4 HiFi Compressor Wheel rated at 375-575 BHP.
	Profile Machine the Compressor Cover & Back-plate to suit the new HiFi Wheel & dramatically increase the air-flow capability of the cover which not only increases air flow by aprox. 100% but also helps lower critical inlet manifold temperatures.
	Radically back-cut the Turbine Wheel & enlarge the Turbine Housing Exducer to increase exhaust gas "dump" & reduce exhaust manifold backpressure.
	Modify the swingvalve choke to resist over-boosting.
	Optional Polished Compressor Cover at no extra cost.