Originally Posted by
corriedw
You don't mention the name of the management system you use. There are always new products on the market, so I stand corrected if I am wrong.
I regularly speak to the guys at a reputable speed shop. They drag race two cars in the SA series and build a half a dozen wild cars a month of all kinds, with part of the owners preferences. They tune two dozen more a month that was build by the owners. So different imported and local management systems turn-up and I haven't seen or heard of one better than OE managements. Another problem is the amount that these systems can retard the timing. A turbo car need double the amount of retardation of the timing than a normally aspirated car.
The latest OE systems like Alfa GTV series 3 and all Direct injection engines use systems that continually advance until knock is detected every time you rev it. We have proved that Alfa OE ECUs can retard enough for a turbo application if A/F ratio is good and boost is low. And lately we used low pressure turbo applications on, non Direct injection cars, with 10:1 and 11:1 compression ratios. Maybe my friend Hennie's GTV is still on MRD's (Minnaar Racing Developments) facebook page. We stuck the turbo to a std engine and it reliably developed 330 wheel horsepower(330 kW on crank) on the dyno at 0.4 bar boost.
Knocking occurs easier at high boost, low RPM situations. The place to look at first is where the boost rise rapidly ie 2500 to 3500 rpm depending on turbo.