Dealership to Dyno: Our FR-S gets measured
 

We picked up our Asphalt Grey FR-S today from Alan Jay Toyota/Scion in Sebring, Florida earlier today. It's a manual with the BeSpoke radio and what I really found surprising was how great this color is, especially in bright sunlight. There is some orange peel that I noticed on the rear decklid, but overall the car is really pretty. After getting over the joy of picking up the new toy, I made my first stop of the day at our friend's shop: Titan Motorsports. They have an AWD Dynojet and our goal was to get a baseline idea of the power numbers and curve.

I'll leave my first driving impressions for another thread, because this is about the baseline pulls we made today (but MAN is this car fun!).

We did 4 pulls, the first 3 were fairly close together and today was a hot day in Orlando, all three pulls were between 160.8 and 161.1whp. We decided to let her rest for a few minutes and turned the fans on high to cool everything down so that there was as little heatsoak as possible.

On the 4th and final run, the car posted 164.7whp:

http://media.firstrule.net/u/123/frsdyno4sm_orig.jpg

Video of the run is coming tomorrow!

I was satisfied with the numbers and I think we have a great baseline to work from. This car at 200whp, with a little less weight and some suspension upgrades is going to be a little rocketship...

Follow us on Facebook, Instagram and here on FT86club to see how we build up our FR-S to make a great platform even better. We have parts in development and will be offering them for sale very soon. The car goes on track next weekend for the first time. Pictures and video to follow.

-Jon

So either the car is over-rated or it has 17%-18% drivetrain loss. :confused0068:

I'd like to see more baseline numbers after 500+ miles and an oil change.

And here's the video:

[ame="http://www.youtube.com/watch?v=KVJJfDp0c1w"]2013 Scion FR-S Dyno - Stock, 164.7 RWHP - YouTube[/ame]


-Jon

I know the specs say that the car is 200whp at 7000rpm... But I don't entirely understand how a dyno works entirely. Is it a 3rd gear pull to a certain rpm/mph? Can somebody explain it simply? And also, simply why its not pulling towards the 200whp zone rather than 164.7whp?

You use the gear that equates most closely to a 1:1 ratio on the torque multiplier (gearing). The reason it pulls less than stated Crank HP is due to parasitic loss in the drivetrain. Pulleys, transmission, wheels, etc leech power from the motor on the way to the rear wheels.

17%-18% driveline loss is appropriate for FR car with manual transmission and an independent rear. In fact, it might be a little high, but that could be a dyno variance. Solid rear axle cars with manual transmissions are in the 12%-15% range. An independent rear or auto will bump that another 2%-5% each.

It's when you start looking at AWD that the numbers really jump since you're nearly doubling the driveline. Subarus will see as much as 26% driveline loss.

The specs aren't whp (wheel horsepower), they are bhp (brake horsepower) which is measured at the crank with a dyno called an engine brake.

It takes power to turn everything connected to the engine, so the more you have connected (transmission, driveshaft, differential, half shafts, and wheels) the more driveline loss you'll see. So whp is a better measurement of the real power seen when driving the car, but bhp sells cars because it's a higher number.

Do you have an AFR readout from that run?

No AFR reading on this run since we weren't doing any tuning. That will likely come soon though.

i assume you couldn't find a tach signal to add that to the graph? thanks for posting. will be curious to see how others do as we get baseline data as well...

91 or 93 octane?

I'm not sure why he printed it with Speed instead of RPM. I only noticed that after I left. The 1/4 tank that the dealer put in had just run down to nearly empty. This run was made on a nearly full tank of 93.

Great Baseline, thank you!

Sounds like the correct power figure, actually very high for a 2.0 Subaru engine. Well done for getting this power from it

Would like to see a power run on a Dyno Dynamics or Mainline dyno ......... anyone?

This dyno looks to be on-par with everyone elses baseline dyno on low-mileage cars. You can reasonably expect a few more HP in a couple thousand miles, but nothing to write home about.

Just a correction: OEM's advertise engine power in crank horsepower, typically done to SAE J1349 [or J2723]. However, OEM's also typically bias their advertising lower than actual in anticipation of a certain engine-build tolerance range at the factory. This is intended to ensure even poorly broken-in engines with on-edge tolerances will make advertised power. OEM's can also bias the advertised number to play games with other brands.

Wheel or hub horsepower measured on a chassis dyno is subject to drivetrain losses and will of course read lower. Getting hung up on the actual number isn't relevant; chassis dynos are best used as comparative tools where you're making back-to-back changes on the same car on the same dyno.

If you want a "real" number, remove your engine from the car and put it in an engine dyno cell and run it according to the SAE methods.

Seems like the pull was done in 4th, I thought the 1:1 gear is 5th on the manual. Can u confirm that?

yes fifth is 1:1 sixth is .77 and fourth is 1.21 on the automatic
fourth is 1:1 on the manual

Does no one let there shit break in anymore?
I've been involved with a lot of motorsports racing and even hold records to date in land speed racing. And through all this you never see someone base horsepower numbers on what the engine does just after assembly. I don't mind the fact that people have gone straight to the dyno without completeing a proper break in procedure, hell its their engine and it tells me later how much power was missing prior to the break in. I could go on for hours about why a break in is important and how everything "breaks in" but I'm afraid it would fall on def ears. I've see everyone pissed off though the years when a manufacture say that a car is going to produce X horsepower but when it is finally released making 5hp less the public responds with pitch forks looking for blood. well I hate to inform everyone that it is not uncommen to loose up to 5% of the potential horsepower do to improper car care while the vehicle is going through its most delicate time ever.

Moral of the story don't base the horsepower number on anything that you don't know was properly broken in. and remember that DYNO packs or hub dynos will show a slightly more favorable number than a wheel dyno.

By the way read your owners manual it tells you how to break in you car.
Below 4k RPM for the first 1000miles and no hard acceleration or braking. and don't cruise at one constant speed. If you have not lived by this than don't expect that engine, transmission and differential to be as efficient as it might be if it were done correctly.

Sir, I believe you have mixed up these transmissions as evident by this image:

http://kaizenfactor.files.wordpress....handout261.jpg

The 6MT has shorter gear ratios than that 6AT, the 6MT 5th gear is 1:1 whereas the 6AT has 4th at 1:1.

There are many different methods and ideals when it comes to engine break in. We were fortunate to have a chassis dyno on the way home and wanted to get a quick baseline. For an engine that is raced and going to be modified we're not too worried about getting to the 200k mile mark. We've always broken engines in the way we intend to use them, well change the oil this week and she'll be on the race track this weekend getting enjoyed.

The shop the dyno was performed at hold quite a few records in it's own book and builds the most powerful Toyota engines on the planet. It was less than ideal conditions with the summer heat and humidity here so I agree the results should be taken with a grain of salt, however for comparison purposes it's a great way to see the starting point.

I would also like to point out one error in the above image, the 6MT is not designated as theRA62, its the TL70 which is derived from the Aisin AZ6 unit.

You could just come out and say Titan....

:D

We'll be dynoing ours on our Dynojet 424xLC2 tonight.

http://www.ft86club.com/forums/showthread.php?t=5404

This post has the gear ratios