RX8Club.com - losing power at 7500 RPM

Hi all,

I have a 03 JDM RX8 that i just purchased in Malaysia. It was imported directly from Japan with very low mileage (2k). I went for a dyno the other day and notice that there was NO speed cut or whatsoever. But when i drove it on the road, the speed cut kicked in and limited my speed to 187km/h. Can anyone tell me how that works?

On a more serious note, during the dyno test, i notice that the power curve on my car declined after 7500 rpm on a 4th gear test at 163km (only up to 4th gear because we thought there was going to be a speed cut)! It dropped like 30 hp! Is that normal? As i understand, the loss of power should not happen until maybe 8000 rpms, but what i saw was odd! The dyno guys told me that my ECU could have been swapped for an Auto's ECU (which cuts off at 7500 rpm). The dyno results showed that the car only produced 191hp on the engine (and this was a JDM model, which means it's supposedly the 250hp model!). I lost 60 hp! Which means, on the wheels, it's a whole lot less!!!

I've yet to bring the car back to the importer to check it out but i would like to hear what you guys have to say. Thanks for your response in advance!

Cheers!