Looking for standard NB8B rwkw figure

aka_juffa · Postby **aka_juffa** » Wed Jan 09, 2013 3:50 pm

For the 2001 model year, The 1.8 L (110 cu in) BP-Z3 engine was slightly modified and now featured variable valve timing on the intake camshaft. The intake and exhaust system also received a minor upgrade. These modifications resulted in a power output of 113 kW (152 bhp) (Japan, UK and Australia) or 107 kW (143 bhp) (US only).

Taken from here http://en.wikipedia.org/wiki/Mazda_MX-5 ... .282001.29

pcmx5 · Postby **pcmx5** » Thu Jan 10, 2013 8:31 am

Techno had a chart of dyno figures from about 3 Vic Club days at Caulfield Jag's Dyno Dynamics dyno and the average loss from quoted flywheel Kw to RWKWwas around 30%.His figures and those at the dyno day I ran in Geelong and some before and after tests when T&C exhaust have been done (again on a Dyno Dynamics but at Daltons in Geelong) put a standard NB8b/C at around 74-78 RWKW.No real difference between them and ussually only 2-3 better than an NB8A.

As a matter of interest NA8A's did not seem to have the power increase that the factory claimed over NA6A's on our figures.

Sorry i have lost Techno's chart but someone here may still have it,

Peter

mazmad · Postby **mazmad** » Thu Jan 10, 2013 8:47 am

Yeah 30% loss. Ouch.

pcmx5 · Postby **pcmx5** » Thu Jan 10, 2013 9:03 am

aka_juffa wrote:For the 2001 model year, The 1.8 L (110 cu in) BP-Z3 engine was slightly modified and now featured variable valve timing on the intake camshaft. The intake and exhaust system also received a minor upgrade. These modifications resulted in a power output of 113 kW (152 bhp) (Japan, UK and Australia) or 107 kW (143 bhp) (US only).

Taken from here http://en.wikipedia.org/wiki/Mazda_MX-5 ... .282001.29

Jeff, not totally sure on this but i think they initially claimed 113 Kw in the US and it didn't have it and they were taken to court over it and in some cases had to take the cars back under US consumer laws.If that is the case hard to imagine the Aussie version having 113KW.

Peter.

93_Clubman · Postby **93_Clubman** » Thu Jan 10, 2013 11:12 am

pcmx5 wrote:
aka_juffa wrote:For the 2001 model year, The 1.8 L (110 cu in) BP-Z3 engine was slightly modified and now featured variable valve timing on the intake camshaft. The intake and exhaust system also received a minor upgrade. These modifications resulted in a power output of 113 kW (152 bhp) (Japan, UK and Australia) or 107 kW (143 bhp) (US only).

Taken from here http://en.wikipedia.org/wiki/Mazda_MX-5 ... .282001.29

Jeff, not totally sure on this but i think they initially claimed 113 Kw in the US and it didn't have it and they were taken to court over it and in some cases had to take the cars back under US consumer laws. If that is the case hard to imagine the Aussie version having 113KW.

Yeah, it got revised back to 107KW due to testing method.

Matty · Postby **Matty** » Fri Jan 11, 2013 11:36 am

pcmx5 wrote:Techno had a chart of dyno figures from about 3 Vic Club days at Caulfield Jag's Dyno Dynamics dyno and the average loss from quoted flywheel Kw to RWKWwas around 30%.His figures and those at the dyno day I ran in Geelong and some before and after tests when T&C exhaust have been done (again on a Dyno Dynamics but at Daltons in Geelong) put a standard NB8b/C at around 74-78 RWKW.No real difference between them and ussually only 2-3 better than an NB8A.

As a matter of interest NA8A's did not seem to have the power increase that the factory claimed over NA6A's on our figures.

Sorry i have lost Techno's chart but someone here may still have it,

Peter

2008 dyno day at Caulfield Jag attached.

Can't remember mods and didn't list them sorry, mostly just intake/exhaust I believe.

My 1999 was bog standard and made 73.5 on the day.

mazmad · Postby **mazmad** » Fri Jan 11, 2013 11:42 am

Interesting, thanks.

Postby **NitroDann** » Fri Jan 11, 2013 11:45 am

The fact that engineers who test engines on an engine dyno for a living cannot decide how much power the engine has within 5kw should tell you how accurate you can be when using chassis dyno figures from the local mechanic.

Dann

mazmad · Postby **mazmad** » Fri Jan 11, 2013 11:51 am

No - what it tells ME is that - you cannot compare from one day to another or one dyno machine to another - but you can compare figures from the same dyno machine in the same session.

Apu · Postby **Apu** » Fri Jan 11, 2013 11:57 am

Ignoring the fluffing of numbers, the reality is that in a production run of engines, there will be some variation in the numbers.

I read an article some years ago (OK, more than a decade ago...) and I think it quoted Ford, saying that brand new engines could vary by about 10-15% on the dyno. I'm sure this has improved now but still...there's going to be some variation.

Then factor in how an engine has been run-in, and maintained... (I digress here but Google how some race bike engines are run-in. I cringed!).

I think I said this earlier as well, but 5-10kW...not going to make a huge difference for most of us on the track. Sure as hell won't for me as I'm not that consistent to eke out that last bit from the car.

Postby **NitroDann** » Fri Jan 11, 2013 11:59 am

I think we are both saying the same thing mazmad.

Dann

mazmad · Postby **mazmad** » Fri Jan 11, 2013 12:44 pm

All good Dann.

APU maybe you don't want it , but if you have a spare 10kw I will have it !

If my std engine is in the vicinity of 75-80kw, then that is nearly 15% increase. Yes please!

bruce · Postby **bruce** » Fri Jan 11, 2013 1:11 pm

.......and, it's still not a lot!

mazmad · Postby **mazmad** » Fri Jan 11, 2013 1:40 pm

Great I'll have 10 off you too!

Apu · Postby **Apu** » Fri Jan 11, 2013 2:31 pm

mazmad wrote:All good Dann.

APU maybe you don't want it , but if you have a spare 10kw I will have it !
If my std engine is in the vicinity of 75-80kw, then that is nearly 15% increase. Yes please!

Haha! I'll keep my 10kW thanks!

Don't get me wrong, I want every kW I can get but I'm sure you get what I'm saying! But it's more likely to be 5kW range in an MX5...I've been thinking of my Integra a lot :oops:

I got a 15-20kW gain on the Integra and that's the first time I could honestly say that I really felt the difference.