i have some sort of boost problem with my supercharger. just abit of background info: its a sc14 over driven 78% (10psi @6000rpm), holden 186 40thou (3.2ltr) with 7.1:1 compression, stage 1 cam (power range 1900-4900 rpm).
anyway, i just got it all running and got it dyno tuned today. it made 123Hp @ 138KPH / 4500rpm, max torque was 813NM @82 km / 2750rpm (in 4th)
when under load, its boosts to 5psi at 2200rpm and holds that till 4000rpm then the boost starts to drop to 4psi as the the revs keep climbing. the motor feels to be making no extra power past 3500rpm and wont even rev past 5000rpm. it seams as if the engine is being starved of air at high rpm. before i had the blower, the engine would rev fine all the way to 5-500. not under load it revs to 7000rpm fine. as the blower has been overdirven, shouldnt the boost keep climbing to approx 10spi with the rpm?
i realise that these blowers can run out of puff at high rpms, but not at 3500-4000 rpm and not at only 5psi. this makes me think there is either a problem with the blower or maybe the belt is slipping. the power curve for Hp is very flat where only a 35hp difference from lowest hp (2680rpm) and highest Hp (4500rpm)
Fri, 23 September 2005 08:57
