BRZ / FR-S Boxer Engine Dyno Powerband revealed
 

Official BRZ/FR-S Boxer dyno chart from the new Official BRZ JDM website


Attachment 4567


Needs a tune ?

Maybe? But then, how much more power would a tune get?
Can you share us the source of this graph? 25% drivetrain loss is quite a lot.

I don't like that dip in the tq curve around 4k rpm. Wonder why...?

Looks similar to the extrapolated curves we saw based on the now deleted video of the 86. Same drop at 4000rpm even. How many kW is that, ~147? 147kW = ~188hp according to the conversion table I'm using. Might be an engine dyno rather than a chassis dyno.

Look at the units. It's kW, not HP. And the dip in 4K, I believe, has theoretically been attributed to the D-4S system switching over injectors.

It's in kW, and 147kW is 197hp as advertised.
OrbitalEllipses, no it hasn't been attributed to that, may I suggest you go read the intriguing discussion we had on this? :)
Port injection is turned off well before 3000rpm. Currently that drop is somewhat of a mystery. I believe it can be tuned away.

Thanks for the heads up on the units. Makes sense now.

Hope the tuners can work their magics and alleviate the torque dip with simple mods like ECU tune (probably not an easy feat to accomplish though...)

Oh? I thought that's what I read on it. Is it in the D-4S thread or the 170rwhp thread? Link?

WHOOPS. Read the wrong line. I was looking at 140kW. So it's chp and not whp...

Also heads up: torque units are wrong. It's in N-m not kg-m.

The dip should not be a problem, as I have it on my Alfa and I with a tune I can flatten it without problem. But with DI it could be different though, but I still don't think so.

Engine tech. Well, arghx7 copied a chart from the 2GR-FSE technical paper that showed the port injection/direct injection usage map. We dug up some info on how VVT-i is controlled, and found that there is a large amount of internal EGR going on for emissions reduction apparently, and the particular way that they set this up could be affecting midrange torque. However seeing that torque is very strong at 3000rpm suggests something else is at work.

However it could just be an intake/exhaust tuning thing, in which case you probably can't dial it out in the ECU.

Without the drop you would get maximum torque from 3.000 RPM to 7.000 RPM what would be a 4.000 RPM band, as better than its turbocharged rivals. It is nice that the torque keeps up to max power.

Agreed on the unwearying tq up to 7k. Very nice indeed! What was the cause of the dip in Alfa (albeit the absence of DI)?

Curious to see how much we can get out of the normative I/H/E and the tune... Hopefully, we will able to see at least 10% gain.

I have a good feeling about N/A on this car. Hopefully alot was left on the table

I'm sorry but that's bs
It sais 200kg/m. Realy? 200nm yea but kgm hell no

They most likely meant 20.0 kg/m or N·m

The sharp drop in torque at 7000 suggests there is probably quite a bit of power that can be picked up imo, yea :)

The specs are 147kW and 205N-m, as per Subaru. The chart is mislabeled, I said that.

The dips in torque and hp may be caused by a valve controlled variable intake, which Toyota uses in many of their engines. What I mean is, by way of a valve, the intake length is effectively changed. All of the dyno charts I have seen from engines that use this type of variable intake suffer from significant dips in torque and slight dips in hp near the switchover point. Some (all?) lexus motors use three stage intakes to better avoid these dips.

That's a good point, I did not think about that for some reason.
The sharp drop at 7000 is a bit strange though, my guess is that will be easy to remove and thus make the last 500 rpm of the rev range more useful.

Perhaps they let off the throttle at 7000? :bellyroll:

In the ECU programming? :bellyroll:

soft fuel cut? it is only ~400 rpm so it is probably intentional to stop people driving hard into the limiter.

Hey, it is DBW after all. :)

With such a precipitous drop off it's either artificial, or the airflow is choking somewhere, hopefully not in the head.

And noone's mentioned yet that that is clearly a very "smoothed" graph - so the sharp cutoff at 7000 will be a transition rather than a quick reduction when we get a true dyno chart.

I would however say that I'm surprised they haven't used different cams to bring the torque band back a bit, bringing the power peak back in the rpm range as well - this should have given a flatter torque curve (less of a dip in the middle), and I don't see why they couldn't have made the same power with that setup... :S Maybe for modifications - maybe the cams are designed slightly more for people raising the stock rev limit or making high flow mods (I/H/E) to get the most power?

After looking at the chart, I feel a big optimistic. The torque maxing out at 3k rpm is very nice indeed. Especially if you want to autox or track this car. I think the lines can be smoothed out with a simple tune and bolt ones, it still won't be a monster. But for autox it might do quite well depending on its class.

that torque table that just plummets after 7k could probably be extended a good bit. its going way too strong for that much of a drop off naturally. heres hoping they left it all on the table, ready for tuners to unlock

does anyone here think they can do an overlay of this graph
http://www.ft86club.com/forums/attac...7&d=1328422528

over this graph (size and strech it accordingly) so i can see how much better the fa20 is compared to a stock 2zz-ge

http://dyno.newcelica.org/sonic/dynorun.jpg

It's not scaled the same...

Yea but the torque drops off more on the 2ZZ (120ft-lb to 100ft-lb before the cams switch) than the FA20's drop at 4000 (200Nm to 180Nm). The FA20 is smoother, although it starts off weak in the low range because of the fixed duration cam.

Freehand bitches :happy0180:

One is at wheels and the other is at crank. Can't compare, so I did it with 15% loss


yellow and purple are best guesses.

midrange torque is dramatically improved.

This is about as good a hp graph as you could hope for. I don't mean total power, but in terms of power delivery this is very nice. Cant wait to see how aftermarket bolt ons change things, my guess is that this engine is very very efficient and bolts on's will not do much.

Its a good enough guess, ty :)
Power delivery is much better, its better than a stock gts, that's all I was hoping for, i'm 100% sold now :)

Once that area(3200-4800) gets fixed this will be my favorite 2.0 liter engine. I wish my RSX made almost 100% of torque from 3k to 6.5k.

I doubt that area will get fixed without sacrificing something significant elsewhere. We have not just magically stumbled upon something that toyota and subaru missed.

So... if anyone's willing to explain in layman's term. Is this a good or bad graph? I have no idea what I'm suppose to look at lol

It is about area under the curve. Overall looks good but as others mentioned a few areas like 3200-4800 need some work. Flat torque is king so is area under the curve. Not so much peak numbers persay.

It's rather impressive considering that it is a fixed cam profile. Very flat from 5000-7000, which is where you'll be if you're revving it. Also it's pretty remarkable that they are able to get so much torque at 3000rpm when the cam is "optimized" for 6000rpm.

The likely explanation for the dip is the intake tuning, a more sophisticated variable intake would help but that would be rather difficult to come up with.

its really good for a 2L 4 cylinder engine that has no valve lift or extremely aggressive cams, gas mileage is also beyond expectations, they did a very good job

valve lift is noticed in the graph i posted with the jump in hp at 6200 rpms..

Lexus already has a more ''complex'' variable intake, its not that complex, just more expensive maybe a little larger/heavier.

The issue would be tuning one and figuring out control systems for a car that doesn't come with it from the factory...can't just transplant a Lexus system over when it's made for an engine with much more displacement.

There is nothing to tune, other than activation point, on these variable intakes, they are either open or closed. We can only hope that MPG and noise constraints left a few HP to be ''unlocked''.

Uh, what do you mean nothing to tune? I don't think Lexus has any 2L engines that you can just pull the intake off and move over. The pipes will be incorrectly sized if you do.

And yes they are either open or closed, but you have to have a separate controller because the ECU doesn't know what to do with a 3 stage intake.