TRD Wheels on a 2018 BRZ

[Jordanwolf]

Originally Posted by NoHaveMSG

@Jordanwolf

Ahhh, that is the camber I need to get a little more heat into the inner third of my tires. Can you share specs?

Sorry these are race specs from Doyogaru. Cannot share.

[nikitopo]

Originally Posted by fatoni

How much more power does the gr 86 have?

The same power with the 14R60 car and you know the result :b

There are at least a dozen of performance variants and special editions cars. Every development team did it differently for various reasons. Not only the tires, but different aspects of the car. Sometimes decisions were made for performance in racing or autox, sometimes for the looks, sometimes for providing an almost ready car and leaving the power upgrade to the customer and so on. Fact is that the official competition race spec car had a 205/55R16 tire.

[fatoni]

Originally Posted by nikitopo

The same power with the 14R60 car and you know the result :b

There are at least a dozen of performance variants and special editions cars. Every development team did it differently for various reasons. Not only the tires, but different aspects of the car. Sometimes decisions were made for performance in racing or autox, sometimes for the looks, sometimes for providing an almost ready car and leaving the power upgrade to the customer and so on. Fact is that the official competition race spec car had a 205/55R16 tire.

So was bringing that car up to show that staggered wheels are for performance or looks?

[NoHaveMSG]

Originally Posted by nikitopo

The same power with the 14R60 car and you know the result :b

There are at least a dozen of performance variants and special editions cars. Every development team did it differently for various reasons. Not only the tires, but different aspects of the car. Sometimes decisions were made for performance in racing or autox, sometimes for the looks, sometimes for providing an almost ready car and leaving the power upgrade to the customer and so on. Fact is that the official competition race spec car had a 205/55R16 tire.

Interesting that they chose that size but the Aus and NZ 86 series spec a 225/40/18.

[RayRay88]

Originally Posted by nikitopo

The same power with the 14R60 car and you know the result :b

There are at least a dozen of performance variants and special editions cars. Every development team did it differently for various reasons. Not only the tires, but different aspects of the car. Sometimes decisions were made for performance in racing or autox, sometimes for the looks, sometimes for providing an almost ready car and leaving the power upgrade to the customer and so on. Fact is that the official competition race spec car had a 205/55R16 tire.

You keep mentioning the Gazoo Race series... get over it. It's a low/entry level, spec series, club race localized only to Japan. It's not the end all be all of 86 Racing.

I want to know why you're not bringing up the Gazoo/TMG 86 CS-V3 and CS-Cup. These compete in VLN and tons of spec races internationally.

They mandate 17x8 wheels.

[Racecomp Engineering]

Originally Posted by nikitopo

Fact is that the official competition race spec car had a 205/55R16 tire.

There's just one official Toyota 86 racecar now?

Is it this one?



Or this one?



What about this one?


I think you might have meant this one but I'm not sure...


You know I have my issues with this factory built car...


I don't know much about these Australian spec cars


And this car rules.


- Andrew

[nikitopo]

Originally Posted by NoHaveMSG

Interesting that they chose that size but the Aus and NZ 86 series spec a 225/40/18.

And changed ..



ECU - Motec with custom program
Exhaust – headers/extractors and muffler
Stripped interior

[nikitopo]

Originally Posted by Racecomp Engineering

There's just one official Toyota 86 racecar now?

All these are local country's spec cars with different changes and specifications. What is your point? The only official regulation car is the Gazoo 86/BRZ spec.

Another example ...
In UK there was in the past a Subaru Cosworth CS400 car. Does it mean that Subaru Japan was officially co-operated with Cosworth? Nope. It was just a local country's project. Or am I wrong?

[Jordanwolf]

Originally Posted by Racecomp Engineering

There's just one official Toyota 86 racecar now?

Is it this one?



Or this one?



What about this one?


I think you might have meant this one but I'm not sure...


You know I have my issues with this factory built car...


I don't know much about these Australian spec cars


And this car rules.


- Andrew

How about this car?

[NoHaveMSG]

Originally Posted by nikitopo

And changed ..



ECU - Motec with custom program
Exhaust – headers/extractors and muffler
Stripped interior

Didn't post that comment to be argumentative though I could see how it could come across that way as I do not know the specs of the Gazoo Series. When I search "Gazoo Racing 86 specs" I just get a bunch of cars built by them. What are the specs? Don't exactly know what we are comparing too.


I understand the upgrades from a stock car vs the Aus. car but weight wise we are not talking much of a difference over a stock car as it is fully caged. And what is a full exhaust with tune worth, 20-25hp at the wheels? Maybe more if they are running race fuel with more aggressive timing? Really, this car as not that far off from how my car is setup, less the stripped interior and cage.

[Racecomp Engineering]

Originally Posted by nikitopo

All these are local country's spec cars with different changes and specifications. What is your point? The only official regulation car is the Gazoo 86/BRZ spec.

I have 2 points.

1. A spec race series never puts together a set of regulations designed to build the ultimate fastest car. That's not the point of a spec series. The parts for a spec series are generally intended to be relatively cheap, easily available, and uncomplicated. For example, the new SCCA SSC spec class here in the US for this chassis requires the use of 225/45/17 Falken tires. Are Falken tires the fastest choice? No. But everyone will be running on the same tire, so the playing field is level AND they're cheap. There also could have been other factors at play (sponsorships, etc). They didn't choose them because they're fast. Lots of spec series are specifically designed to be tire limited!

2. Who said the Japanese Gazoo cars are the only "official" regulation Toyota racecar? TMG is Toyota Motorsport GmbH (TMG) and they have a spec for track, tarmac rally, and gravel. Toyota Australia has their own spec. TRD has their car (which I think is basically a TMG car). And so on. Which one is most "official"? Is TMG less official than Gazoo? Who cares? To me it doesn't matter.

Can 205/55/16 tires be fast? Yeah of course. Are they always the best choice? No.

There are lessons to be learned from a spec class car. But they aren't universal and you have to look at the full picture.

- Andrew


(I still have my 205/55/16 winter tires on my car....lol)

[Racecomp Engineering]

I do think a lot of people way overtire and overwheel these cars for what it's worth.

- Andrew

[NoHaveMSG]

Through careful examination of this thread I have concluded everything is wrong and I am a carrot.

[rvoll]

Originally Posted by Icecreamtruk

Bro, you have some twisted concepts of how things work so Im going to leave this here. Since to you weight transfer is the effect that body roll has, would a kart, that has no suspension, and thus, no body roll, have no weight transfer at all?

Any platform where the center of gravity is above the ground will have a moment of inertia and increase downforce. The issue is the AMOUNT of downforce on the wheel. The more body roll, the more downforce because the center of gravity rises higher with body roll. Capish? The lower the COG, the less the increase in downforce and the more you'll see lateral forces. In a car with a low COG like the Twins, there will be significantly more lateral force on a turn than downward force. In an equation, think of the axle as a lever with a constant mass (i.e., weight of the car). With a longer lever (i.e., increased width), the downward pressure on the wheels is actually less because of that leverage action. Think about moving a stone on the ground with a longer stick. Conversely, the downward pressure with a lesser width is slightly higher. The advantage of a wider track is that you would get less body roll. But it is not that simple. You want to maximize the adhesion of the tire. There is a point where added downward pressure does not increase tire adhesion because you are at the limits of the tire. It's a matter of balance in terms of getting the right downward and lateral pressures against the right contact patch and tire compound. The balance also includes handling considerations. If a car is well designed for a certain track, then deviation from that track, in either direction, will make the car less balanced. There are so many variables to consider, that no one theory will apply. If you want to race a car, you can increase the track and modify the suspension to get optimum results. But then that is a different design.

The BRZ is a well designed car and every review I've seen says it is extremely well balanced. Why go to a wider track and put strain on your suspension (and alignment) when you have such a car. Small differences should have small effects. Again, proper testing is difficult because not only do you have to have wheels with different offsets, or if you use spacers you need longer studs, but you have to do an alignment each time and run blind tests.