Best Springs for Handling?

[Racecomp Engineering]

killboydotcom had a pretty good summary on understeer vs oversteer.

Understeer does have a negative connotation which is why CSG Mike used that term. In reality though, it's a little more complicated. And to say our springs simply "understeer" is misleading at best. They handle well and are predictable.

We looked at available bump travel, shock dynos of the OEM dampers, and suspension geometry (kinematic roll centers and FAPs as well as the camber curve).

Our springs use the same spring rates front and rear as opposed to firmer spring rates in the rear like factory. Strictly looking at spring rates, yes that would mean an increase in understeer. But if you're strictly looking at spring rates, you're not very good at this sort of thing.

There are three things to keep in mind:

1. Our springs use replacement shorter bumpstops front and rear. This is a pretty big deal...otherwise when you lower an inch, you're using the factory progressive bumpstops in every corner and those things are stiff. So the published spring rates aren't the only thing at play.

2. The front of the car has a very different camber curve than the rear of the car. When you're lowered, you're already at a disadvantage here and stiffer front springs that keep that change to a minimum is one way to go.

3. The geometry of the car up front changes with a drop in a way that makes the front of the car want to roll more...one way to counteract this is stiffer front springs.

There are other ways to go too...stiffer rear rates do indeed help reduce understeer and we could have gone with firmer rears in conjunction with our current fronts but we felt that would put the rear shocks closer to their limit of what they could properly handle. With any spring you need a good alignment and that's always going to be crucial to a car's balance.

The factory spring rates work well at factory ride height. The engineers had design goals and limitations and had to make compromises.

I don't have anything bad to say about Eibach Pro-kit, Swift, or Hotchkis springs. We just went a different route that we like better. Like OEM or even our springs, you can make them understeer AND oversteer.

It's a great balance for a daily driver that occasionally autocrosses, hits the canyons, or takes their car to the track. Fast, good ride, confidence building, and just plain fun. If you upset the balance of the car and either understeer or oversteer, it's very smooth and easily controllable.

- Andy

[HachiRo]

Originally Posted by Racecomp Engineering

killboydotcom had a pretty good summary on understeer vs oversteer.

Understeer does have a negative connotation which is why CSG Mike used that term. In reality though, it's a little more complicated. And to say our springs simply "understeer" is misleading at best. They handle well and are predictable.

We looked at available bump travel, shock dynos of the OEM dampers, and suspension geometry (kinematic roll centers and FAPs as well as the camber curve).

Our springs use the same spring rates front and rear as opposed to firmer spring rates in the rear like factory. Strictly looking at spring rates, yes that would mean an increase in understeer. But if you're strictly looking at spring rates, you're not very good at this sort of thing.

There are three things to keep in mind:

1. Our springs use replacement shorter bumpstops front and rear. This is a pretty big deal...otherwise when you lower an inch, you're using the factory progressive bumpstops in every corner and those things are stiff. So the published spring rates aren't the only thing at play.

2. The front of the car has a very different camber curve than the rear of the car. When you're lowered, you're already at a disadvantage here and stiffer front springs that keep that change to a minimum is one way to go.

3. The geometry of the car up front changes with a drop in a way that makes the front of the car want to roll more...one way to counteract this is stiffer front springs.

There are other ways to go too...stiffer rear rates do indeed help reduce understeer and we could have gone with firmer rears in conjunction with our current fronts but we felt that would put the rear shocks closer to their limit of what they could properly handle. With any spring you need a good alignment and that's always going to be crucial to a car's balance.

The factory spring rates work well at factory ride height. The engineers had design goals and limitations and had to make compromises.

I don't have anything bad to say about Eibach Pro-kit, Swift, or Hotchkis springs. We just went a different route that we like better. Like OEM or even our springs, you can make them understeer AND oversteer.

It's a great balance for a daily driver that occasionally autocrosses, hits the canyons, or takes their car to the track. Fast, good ride, confidence building, and just plain fun. If you upset the balance of the car and either understeer or oversteer, it's very smooth and easily controllable.

- Andy

You guys got a new (or well, near future) customer!
Thanks so much for all the info

[Racecomp Engineering]

@HachiRo check out our facebook and/or pickup the April 2015 SPORTS CAR Magazine for a really good article from Randy Pobst. He's a 4 time SCCA World Challenge champion, 2 time class winner at the 24 hours of Daytona, and winner of a bunch of other stuff. Basically, he knows what he's talking about...

He talks about the "friction circle" and what he looks for in terms of understeer/oversteer balance from a car.

He also happens to be talking specifically about the "best handling car ever", a BRZ with a set of Racecomp Engineering Tarmac 2 coilovers...but that's not the point.


- Andy

[CSG Mike]

Originally Posted by Strife26

Is there ever a plus to understeer besides suicide?

Absolutely!

For a newer driver that has never experienced oversteer, understeer is a much safer way to experience a loss of traction/grip, or overcoming the amount of grip the tires have to offer. Additionally, the instinctive response to let go of the throttle when you lose grip typically results in a reduction in understeer, whereas with oversteer, lifting usually guarantees a spin (the proper response is to stay on the throttle and correct with the steering wheel, but this is something that is counterintuitive).

[Strife26]

Originally Posted by Racecomp Engineering

killboydotcom had a pretty good summary on understeer vs oversteer.

Understeer does have a negative connotation which is why CSG Mike used that term. In reality though, it's a little more complicated. And to say our springs simply "understeer" is misleading at best. They handle well and are predictable.

We looked at available bump travel, shock dynos of the OEM dampers, and suspension geometry (kinematic roll centers and FAPs as well as the camber curve).

Our springs use the same spring rates front and rear as opposed to firmer spring rates in the rear like factory. Strictly looking at spring rates, yes that would mean an increase in understeer. But if you're strictly looking at spring rates, you're not very good at this sort of thing.

There are three things to keep in mind:

1. Our springs use replacement shorter bumpstops front and rear. This is a pretty big deal...otherwise when you lower an inch, you're using the factory progressive bumpstops in every corner and those things are stiff. So the published spring rates aren't the only thing at play.

2. The front of the car has a very different camber curve than the rear of the car. When you're lowered, you're already at a disadvantage here and stiffer front springs that keep that change to a minimum is one way to go.

3. The geometry of the car up front changes with a drop in a way that makes the front of the car want to roll more...one way to counteract this is stiffer front springs.

There are other ways to go too...stiffer rear rates do indeed help reduce understeer and we could have gone with firmer rears in conjunction with our current fronts but we felt that would put the rear shocks closer to their limit of what they could properly handle. With any spring you need a good alignment and that's always going to be crucial to a car's balance.

The factory spring rates work well at factory ride height. The engineers had design goals and limitations and had to make compromises.

I don't have anything bad to say about Eibach Pro-kit, Swift, or Hotchkis springs. We just went a different route that we like better. Like OEM or even our springs, you can make them understeer AND oversteer.

It's a great balance for a daily driver that occasionally autocrosses, hits the canyons, or takes their car to the track. Fast, good ride, confidence building, and just plain fun. If you upset the balance of the car and either understeer or oversteer, it's very smooth and easily controllable.

- Andy

IM NOT THAT GOOD AT THIS SORT OF THING! Ahhh. Haha thanks for the awesome result. Looking at your springs too not pricey at all. Love it. Exhaust, headers, then springs maybe.

[Captain Snooze]

Also keep in mind that steering is not an all or nothing, black or white subject. There are degrees of over and under steer. Small amount over static understeer can be balanced on the throttle. Too much over steer is, well, too much.
Plow<-------Neutral------->Pirouette

[Captain Snooze]

Originally Posted by Racecomp Engineering

He also happens to be talking specifically about the "best handling car ever", a BRZ with a set of Racecomp Engineering Tarmac 2 coilovers...but that's not the point.

[Kostamojen]

The best thing I've seen that really shows the "understeer" and the "oversteer" that people are talking about here with our cars, was the Best Motoring video with the GT86 vs BRZ vs MX-5.

Sadly, that video is nowhere to be found online anymore...

But during the race, the BRZ and GT86 go at each other on the course and you can clearly side by side see the differences in the spring rates and how it changes the cars in terms of understeer/oversteer.

[Gunman]

Understeer you hit the wall with the front of your car.

Oversteer you hit the wall with the back of your car.

[Agent 86]

Originally Posted by Strife26

Is there ever a plus to understeer besides suicide?

IMO, on our public roads that are driven mostly by distracted, inexperienced drivers, in cars with more power than those drivers should have, YES! There is a plus.

For the sake of us all, those drivers should not be behind the wheel of cars that oversteer.

[Takumi788]

Originally Posted by BRGT86

i love my hotchkis springs too.

but im not gonna lie, after a year with these on, the wheel gap (a little better than stock though) is starting to bother me now hahah

What wheel gap? Aside from me being to conservative on the tire setup (should have gone with 245/40/18 instead of 235/45/18) I think it looks great with the Hotchkis springs.

[Calum]

I've got about 20,000 kms on my RCE yellows. I went with them because they weren't designed using the same tired formula, but were designed to work with the geometery and damping of car.

My personal impressions are that they are an excellent upgrade. They are much more predictable at the limt than the stock springs, and when they do let go in a static turn it is extremely predictable and easy to recover from. Glorious amounts of oversteer is still easy to induce, just like the stock setup. But what I wasn't expecting is that the ride was actually better than stock. Not smoother per se, just less jarring over the larger bumps. I'm guessing here, but it seemed to me that the stock setup was just too soft in the front until it hit the bumpstops, then things got stiff in the hurry. That was great for inducing snap oversteer when you didn't want it/got a little ham fisted, but I didn't really appriciate it.

[ATL BRZ]

Loved my RCE yellows while I had them. Love my RCE T2's now.

[8R6]

Originally Posted by Takumi788

What wheel gap? Aside from me being to conservative on the tire setup (should have gone with 245/40/18 instead of 235/45/18) I think it looks great with the Hotchkis springs.

i think 18s with 235/45 fill out the wheel well better in general
im on 17x9 with 245/40 tires and here's my wheel gap with a 1" drop: