What the Yaris community needs to take the Yaris to the next level

[regal]

Originally Posted by ChinoCharles

Oh and yeah, that terrible gas mileage post is totally false. My gas mileage didn't change a bit.

You had to have taken a 30% hit just running 93 octane. Fact is there is no elegant OBDII scan compliant way to tune a FI Yaris. If your running a piggy back to keep the OBDII port you must be running dangerously lean to not see a decline in mpg. If you threw away the OEM ECU and OBDII you have an off-road vehicle in most states.

This has been a great discussion and hope it opens some eyes to what a great platform the Yaris could be.

Lack of an ECU hack and simple lack of performance data with various mid-level suspension upgrades are all we need to keep the ball rolling.


I installed TRD springs, Kokico Blue shocks, and a TRD sway bar on the rear axel today, its like a new car literally. Doing the fronts tomorrow. I have a funny feeling that the car will handle better with the stock shocks/springs up front, maybe even better with the front sway bar removed. But we need data. Can you tell I am an engineer (Harley-Davidson)?

Keep the dialog going, I don't mind being told I am wrong about things, it wouldn't be the first time my info was out of date.

[Loren]

Originally Posted by regal

I installed TRD springs, Kokico Blue shocks, and a TRD sway bar on the rear axel today, its like a new car literally. Doing the fronts tomorrow. I have a funny feeling that the car will handle better with the stock shocks/springs up front, maybe even better with the front sway bar removed. But we need data. Can you tell I am an engineer (Harley-Davidson)?

You're right, the car probably will ultimately handle better with the TRD springs and stiffer shocks on the rear and the stockers up front. It will look goofy (too tall in the front), and the steering response will be sloppy because the front will be so soft... but I would expect almost no understeer from a setup like that!

Ditto with removing the front swaybar. It's going to make the front end feel sloppy, but in spite of feeling a little off, it's going to stay HOOKED UP.

If you're an engineer, then you know that any data is only valid in its test environment when all outside variables are controlled. That's one of the hardest things about working with suspension OUTSIDE of a controlled test environment. Things change. Everybody's on different tires, the weather is different from day to day, tire pressures vary, road conditions vary, and on and on.

Best you can do is find a safe place to test and come up with a valid test method. Run a skidpad of of a fixed diameter and time two laps in each direction and take the average. (you can calculate the G's from that if you really want to, but it's not relevant) Make ONE change to the car and try it again. If you make more than one change between tests, you'll never really know which one worked.