Hello,

I just read a thread where someone say that he HP of high-power RX8 is 175 HP...

3 US RX8 were tested and the result is 170-175 HP !

Is the ECU limits the power for a little time ?

Thanks

[ben]

PS : excuse-me for my bad english, I'm from switzerland

 

Ben

certainly I dont think you'll get a reply from anyone in the Europe forum as we certainly don't know. Only a few of us have even taken a test drive, let alone been able to dyno the cars!

 

Perhaps someone heard something of interesting on this problem...

 

they dynos reporting 175-180hp are for rear wheel horsepower, as opposed to horsepower at the flywheel which is what is normally advertised. RWHP typically has 17-20% less HP than flywheel HP for all RWD cars

 

175RWHP ?

No ******* way.......even with 20% drivetrain losses, a 230HP RX8 will put down AT LEAST 230-(230*0.2)=194RWHP.
This figure is probably for the STD-Power RX8........

 

It appears that there is still some discrepency between the 'official' mazdat Bhp at the flywheel, and the results achieved at the rear wheels by dyno testing cars.

As 'The Ace' says, we should be getting around 195bhp at hte rear wheels from the european high power, with the americans getting about 205 from theirs.

But so far I don't think anyone has seen better than 180hp at the rear wheels.

There is a suggestion that the engine management system is deliberately running the fuel mixture rich to prevent engine wear in the early miles on the car. But no-one knows when this will switch off, and Mazda have not admitted that this happens at all.

We will just have to wait and see.

 

Putting the car on the dyno requires also connecting a wide-band (02) sensor on the exhaust, in order to measure the 02 levels, and thus the A/F ratio.

So, if the ECU is running the car very rich, it should be quite obvious to anyone with the slightest experience in dyno-tuning. In order to lose 20-30WHP, the ECU would have to run the engine at a 10% worse A/F than the optimum. So a 12:1 would become 11:1, and a 11:1 would become a 10:1. Such differences should be rather obvious.......

 

OK - I have a 144BHP 1200Kg Xedos that I know does 0-60 in 8.5 secs .... tomorrow I'm testing the RX-8 .... I'll let you know how much faster it feels .... If it's not like ****-off-a-shovel there is definitely a HP/torque problem

 

Looking forward to it mate? Hope you sleep!

What time is the test drive? Just in case I'm on the A3 tomorrow, I want to see the look on your face going over a ton up the hill going towards Guildford in 4th!!!!

Si