Video - Why We Race: Testing Project FR-S at the 2012 Global Time Attack

[Hotchkis]

[ame="http://www.youtube.com/watch?v=aheTlLXBthk"]Why We Race - Testing Project FR-S at the 2012 Global Time Attack Super Lap Battle - YouTube[/ame]

Racing is a vital part of the development of all of our suspension systems. We do this to ensure that our suspension performs as well on the track as it does on the street - delivering the level of performance you demand. So on November 7th, 2012 we took our Project FR-S out to Buttonwillow Raceway Park for the Global Time Attack Super Lap Battle Finals. We had a great time and really got to show that with simple, bolt-on parts you can compete with all-out race cars. Despite our severe power deficit we managed a respectable 5th out of 7 and clocked a

.989 - mere seconds behind some very serious race cars.

Hotchkis Project 2013 Scion FR-S:
Hotchkis Sport Springs
Hotchkis Sway Bars
Hotchkis Caster/Camber Plates
Hotchkis Front & Rear Strut Braces
Hotchkis Harness Bar
Falken 615k Azenis Tires 235/40R18
HRE C106 Competition Wheels 18 x 9
Stoptech Front Brakes
PST/Rally Sport Direct Carbon Fiber Driveshaft
APR Performance Carbon Fiber Brake Ducts
APR Performance Carbon Fiber Engine Cover
Downforce USA Carbon Fiber Front Splitter and Side Skirts
Aero Jacket Carbon Fiber Hood
Project Kics R40 Lug Nuts
Magnaflow Exhaust
T1R Shift Knob
T1R Tinted Concave Side Mirrors
T1R Aluminum Diff Bushing Inserts

[swift996]

Nice, I plan on getting the Hotchkis Front Strut Tower Brace and both front and rear Sway Bars.

I wanted the sway bars for my M3, but they were on back-order forever so I went with the Turner MotorSports (BMW) sways.

[Hotchkis]

Originally Posted by swift996

Nice, I plan on getting the Hotchkis Front Strut Tower Brace and both front and rear Sway Bars.

I wanted the sway bars for my M3, but they were on back-order forever so I went with the Turner MotorSports (BMW) sways.

Sorry your M3 sway bars were backordered Swift, it happens from time to time. Our FR-S/BRZ Strut Tower Brace and Sway Bars are in stock and ready to ship though.

[iLuveKetchup]

Were you sponsored by Falken? Wondering why Azenis tires were used?

[Hotchkis]

Originally Posted by iLuveKetchup

Were you sponsored by Falken? Wondering why Azenis tires were used?

We have a very good relationship with Falken and have used the RT-615K tires on everything from Import Cars to Muscle Cars. We have found that they work very well for street use, autocrossing, and mild track use. They were the perfect tire for the Global Time Attack Super Lap Battle since we were in the Street class which requires a tire of 180 treadwear or higher.

[Dezoris]

There are a lot of parts on that car, so it's hard to draw conclusions as to which made the largest difference.

So let me first say, it's nice to see someone design parts and track test them to prove worth...

Now here are my questions:

1. What spring rates did you choose or what was the increase over OEM.
2. Did you choose to raise the front rates more than the rear?
3. What size is your front sway bar?
4. What was handling deficit you were trying to improve from the OEM setup?
5. Did your combo of springs and front bar, neutralize the balance of the car and which part helped more, springs or sway bar?

[switchlanez]

Care to share the artist/name of the music track used in the video?

[Hotchkis]

Originally Posted by Dezoris

There are a lot of parts on that car, so it's hard to draw conclusions as to which made the largest difference.

So let me first say, it's nice to see someone design parts and track test them to prove worth...

Now here are my questions:

1. What spring rates did you choose or what was the increase over OEM.
2. Did you choose to raise the front rates more than the rear?
3. What size is your front sway bar?
4. What was handling deficit you were trying to improve from the OEM setup?
5. Did your combo of springs and front bar, neutralize the balance of the car and which part helped more, springs or sway bar?

Great questions Dezoris. Hopefully this helps clear things up. Let us know if you have any more.

1. What spring rates did you choose or what was the increase over OEM.
Front spring rates are 185 lbs/in (3.3 kg/mm) which is a 45% increase over the stock FR-S and a 20% increase over the stock BRZ. Rear spring rates are 265 lbs/in (4.7 kg/mm) which is a 25% increase over the stock FR-S and a 35% increase over the stock BRZ.
2. Did you choose to raise the front rates more than the rear?
Yes and no. For the FR-S the front rates are increased more than the rears, while the BRZ has the rears increased more than the fronts. This brings the suspension to an inherently neutral setup instead of the built-in oversteer of the FR-S and understeer of the BRZ. With a neutral setup it is up to the driver whether the car will oversteer or understeer and is based on the control of weight transfer by braking, accelerating, and steering.
3. What size is your front sway bar?
Our front sway bar is a 1-inch tubular bar with 2 stiffness settings. The first setting is 500 lbs/in (170% stiffer than stock) and the second setting is 630 lbs/in (245% stiffer than stock). Our rear bar is a 3/4-inch (19mm) 4-way adjustable blade-style bar. The first setting give you a rate of 320 lb/in which is 200% stiffer than stock. The second setting is 405 lbs/in which is 275% stiffer than stock. The third setting is 520 lbs/in which is 385% stiffer than stock. And the fourth and stiffest setting is 700 lbs/in which is a whopping 550% stiffer than stock.
4. What was handling deficit you were trying to improve from the OEM setup?
The handling deficit we were trying to improve from the OEM setup is the overall balance of the car. While the OEM pieces are work well when still running the OEM Prius tires, a stickier tire will quickly overwhelm the springs and sway bars resulting in much more body roll and more abrupt weight transfer.
5. Did your combo of springs and front bar, neutralize the balance of the car and which part helped more, springs or sway bar?
All of our parts are designed to work together to create the best handling car possible. That is why we package our springs and sway bars together as a Total Vehicle System (TVS). But each part helped improve a different part of the vehicles' handling dynamics. The springs lower the center of gravity and neutralize the inherent under/oversteer of the different cars. The increased spring rate also better matches with the damping rate of the OEM shocks/struts as the car is over-dampened and under sprung from the factory (trick by OEMs to create a "sporty" feeling car). The lowered CG and increased spring rates also work to lessen the severity of weight transfer to give the driver more control. Our sway bars give you the next level of control and add adjustability to the handling. The stiffer sway bars help to keep body roll to a minimum, especially once stickier tires are added. Having the massive amount of adjustability also lets the driver tailor what the car's overall balance will be - neutral, understeer, or oversteer. Additionally, having 4 adjustment settings on the rear bar allows the driver to compensate for the uneven grip caused by staggered tire setups.

[brewksy]

Links to results online?

[Hotchkis]

Originally Posted by brewksy

Links to results online?

Results are here: http://www.globaltimeattack.com/2012...rk-nov-7-2012/

[Silp3]

Originally Posted by Hotchkis

Great questions Dezoris. Hopefully this helps clear things up. Let us know if you have any more.

1. What spring rates did you choose or what was the increase over OEM.
Front spring rates are 185 lbs/in (3.3 kg/mm) which is a 45% increase over the stock FR-S and a 20% increase over the stock BRZ. Rear spring rates are 265 lbs/in (4.7 kg/mm) which is a 25% increase over the stock FR-S and a 35% increase over the stock BRZ.
2. Did you choose to raise the front rates more than the rear?
Yes and no. For the FR-S the front rates are increased more than the rears, while the BRZ has the rears increased more than the fronts. This brings the suspension to an inherently neutral setup instead of the built-in oversteer of the FR-S and understeer of the BRZ. With a neutral setup it is up to the driver whether the car will oversteer or understeer and is based on the control of weight transfer by braking, accelerating, and steering.
3. What size is your front sway bar?
Our front sway bar is a 1-inch tubular bar with 2 stiffness settings. The first setting is 500 lbs/in (170% stiffer than stock) and the second setting is 630 lbs/in (245% stiffer than stock). Our rear bar is a 3/4-inch (19mm) 4-way adjustable blade-style bar. The first setting give you a rate of 320 lb/in which is 200% stiffer than stock. The second setting is 405 lbs/in which is 275% stiffer than stock. The third setting is 520 lbs/in which is 385% stiffer than stock. And the fourth and stiffest setting is 700 lbs/in which is a whopping 550% stiffer than stock.
4. What was handling deficit you were trying to improve from the OEM setup?
The handling deficit we were trying to improve from the OEM setup is the overall balance of the car. While the OEM pieces are work well when still running the OEM Prius tires, a stickier tire will quickly overwhelm the springs and sway bars resulting in much more body roll and more abrupt weight transfer.
5. Did your combo of springs and front bar, neutralize the balance of the car and which part helped more, springs or sway bar?
All of our parts are designed to work together to create the best handling car possible. That is why we package our springs and sway bars together as a Total Vehicle System (TVS). But each part helped improve a different part of the vehicles' handling dynamics. The springs lower the center of gravity and neutralize the inherent under/oversteer of the different cars. The increased spring rate also better matches with the damping rate of the OEM shocks/struts as the car is over-dampened and under sprung from the factory (trick by OEMs to create a "sporty" feeling car). The lowered CG and increased spring rates also work to lessen the severity of weight transfer to give the driver more control. Our sway bars give you the next level of control and add adjustability to the handling. The stiffer sway bars help to keep body roll to a minimum, especially once stickier tires are added. Having the massive amount of adjustability also lets the driver tailor what the car's overall balance will be - neutral, understeer, or oversteer. Additionally, having 4 adjustment settings on the rear bar allows the driver to compensate for the uneven grip caused by staggered tire setups.

There are a lot of choices in regards to the front and rear sway bar. I am not about to test and feel out all four settings for the rear and the two for the front. what do you recommend for a neutral handling with no oversteer nor understeer for street usage?

[Hotchkis]

Originally Posted by Silp3

There are a lot of choices in regards to the front and rear sway bar. I am not about to test and feel out all four settings for the rear and the two for the front. what do you recommend for a neutral handling with no oversteer nor understeer for street usage?

That really depends on your suspension upgrades and wheel/tire upgrades. If you let me know what you have done, I can ask our Engineer (who owns an FR-S) and get his input.

[JB1]

More info on the harness bar ! Looks awesome. Thanks for all the info your sharing.

[BRZ?]

Is it it practical to run the springs and sways with the stock wheel/tire?