Here is what i've been waiting to see typed up in the forums for a while.

Have a look at this statement by 350evo.

"We have had a 3 stock engines on an engine dyno .........not one of the three engines made 287 horsepower."

https://my350z.com/forum/showthread....9&pagenumber=3

Here is the thread, he talks about it on page 3.

I always suspected that with 150rwkw standard we are more or less putting out 190kw and not the 206kw advertised.
Nissan just never expected some bad *** American to dyno the engine.

Good luck to him, apparently 350evo is doing really well in that GTP style race.

As for me, i always felt a tad ripped off untill i put on the Hi-tech. It ***** me that We have to go aftermarket to get up to the rated power.

 

Dynos are very 'subjective' ... the actual power reading does not have any real meaning or value. They have an 'arbitary' scale which is multiplied with a scaling factor to get a semi-meaningful numbers out of them. Not only that, but the reading is always at the 'wheels' while the manufacturers claim the power at the 'crank' (ie. before the drivetrain losses).

Still, dynos are usefull to compare cars/mods ... if you stick to the same dyno and same variables/conditions then it should give you an indication of the differences/gains.

Going by that the 350Z dynos (in the States) at around 240hp. On the same day they dynoed a few S2000's and they returned around 200hp. That is around 30kW difference between the two cars - which seems to fit with the manufacturers claims (at the crank).

 

I always felt the stock car was underpowered for a sports car, but I assumed it was my elevation. I've yet to drive the car at sea level, but I had to put FI in my car to get the power I thought I would have when I bought the car.

 

Some of the more complex dyno's ( Bosch ) can give quite an accurate drivetrain loss indication by monitoring the rate of roller decel. after a power run - ie the dyno is driving the transmission components only ( clutch in ).
If you can find one of these dyno's you can get a reasonable indication of crank and wheel kw also.

 

I think that manufactures rate there engines without any accessories attached ie alterators, steering pumps, gearbox etc.

David

 

DavidM you haven't read the thread... 350evo have taken the engine out of the car and put it on a crank dyno.

Thats a world appart from rear wheel dynos.

He stated that out of the 3 engines they have NONE made the rated power! In the USA that is 287 hp...

If that doesn't give you the ***** then what does?

 

DavidM you haven't read the thread... 350evo have taken the engine out of the car and put it on a crank dyno

I read it after my post :-) Still, I have seen a fair few US 350Z dynos (at the wheel) and they seem to fit in with the 206kW claim (at the crank) when compared to other cars ... like the S2000 for example.

Though, I was dissapointed with the power of the 350Z 1st couple times I drove it .... I thought it was the power delivery and not actually the power. The ride in the Hitech exhaust car saitisfied my power 'needs' though.

On the other hand, in Germany they have already clocked the 350Z at 5.8 sec for 0-100kph and at 13.6 sec for 0-160kph. Those figures are very good for a 206kW/1450kg car. Here, localy they returned 14sec flat for the 0-160kph and that is with 2 people on board and in the 1st few tests. I would not be surprised to see sub 14 sec 0-160kph locally in a not too distant future.

Then when you look at the numbersin the US magazines, they are not as good as expected (at least so far) ... US is renowned for getting the 'best' out of cars as they publish the best run and with minimal weight. With all that the 0-160kph (ie. 0-100mph) time is often in low 14s while I'd expect them to be in mid 13s.

So who knows? Lots of conflicting information (even in this post) but the dynos I've seen seem to be in line with the 'claims' and there are magazines (in some places/countries) that are returning numbers that are very good even for the 206kW 'claim'.

 

That's my understanding as well.

 

Thats right Aps, thats why they pull it out of the car. They will have a preset "standard" for ambient temp, oil viscosity etc.. and the dyno will be pretty accurate since there is nothing attached at all.

BTW the USA have 214kw, we have 206 as well as Japan.

I was just curious if anyone could be bothered removing the engine to do this (as it's a sh!tfight to do). So i was pretty taken back by his post.

350evo doesn't seem to care anyway, he's doing very well with the better handling car that the 350z is.

 

If Nissan was going to over-estimate the power, why would they use an odd number like 287? Why just add 3 more and make it an even 290?

 

I doubt they over estimated the hp output. I just think they got the best engine they ever tested and put those results in the stats.

 

Not saying they did but if I was going to, I'd use an odd number. It looks more believable on paper than a round number.