Eibach Sway Bars
If you still want to try and improve handling try looking into getting coilovers. They're a bit pricier but its a different way to improve handling other than sway bars.
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When you reduce body roll by using a stiffer roll bar, you are INCREASING the "roll stiffness". This means the outside wheel has MORE weight and the inside wheel has LESS when turning. This is great when you have high traction but can be slippery when you have low traction like when turning quickly in the rain/snow. The end with the higher roll stiffness will slide first - ALWAYS!
This is why many people add a stiffer rear roll bar, as it will REDUCE understeer and "feel" better. I hope they have the skill to "catch" the car when the rear wants to be in the front - oversteer can bite you in the A$$.
With any mod, be careful when "testing out" the new modification.
In my opinion the "Sport" suspension in the G37 is FANTASTIC and much better than most stock vehicles.
Now if you have money burning a hole in your pocket, look at getting an intake or exhaust. OR better yet, sign up for a high performance driving school
I don't know if I would use the word fantastic. The OEM suspension on the RWD Sport Sedan is certainly better than most cars. But as a sport sedan, its predisposition to understeer was maddening, IMO. Swaybars solved that problem like a silver bullet.
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I only did one track day in my G37 Sport in 2016, and it was AWESOME.
But of course, my G37 is the BEST one ever made
Of course, you're right, and if I were a better driver then I wouldn't need to eliminate a problem of my own making by throwing upgrades at the car. But in this case I stand by my complaint... with stock tires & sizes, the car understeered every time you pushed hard on a turn.
If I had to rank mods, aftermarket swaybars are #1, with the RJM clutch pedal a close second. Sonic, this is where you point out how if I knew how to operate my 6MT better, I wouldn't have needed to upgrade the clutch pedal.
Last edited by Rochester; Jan 3, 2017 at 10:16 PM.
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Joined: Dec 2015
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If understeer is a problem, bump up the rear tire pressure 1-5 psi. It helps!
However, I suspect that you have already sorted it out, so I will shut my mouth - sometimes I think I come across as a "know it all", but I don' t mean to.
However, I suspect that you have already sorted it out, so I will shut my mouth - sometimes I think I come across as a "know it all", but I don' t mean to.
Joined: Oct 2011
Posts: 6,103
Likes: 594
From: People's Republic of IL
Let me clarify:
When you reduce body roll by using a stiffer roll bar, you are INCREASING the "roll stiffness". This means the outside wheel has MORE weight and the inside wheel has LESS when turning. This is great when you have high traction but can be slippery when you have low traction like when turning quickly in the rain/snow. The end with the higher roll stiffness will slide first - ALWAYS!
This is why many people add a stiffer rear roll bar, as it will REDUCE understeer and "feel" better. I hope they have the skill to "catch" the car when the rear wants to be in the front - oversteer can bite you in the A$$.
With any mod, be careful when "testing out" the new modification.
In my opinion the "Sport" suspension in the G37 is FANTASTIC and much better than most stock vehicles.
Now if you have money burning a hole in your pocket, look at getting an intake or exhaust. OR better yet, sign up for a high performance driving school
When you reduce body roll by using a stiffer roll bar, you are INCREASING the "roll stiffness". This means the outside wheel has MORE weight and the inside wheel has LESS when turning. This is great when you have high traction but can be slippery when you have low traction like when turning quickly in the rain/snow. The end with the higher roll stiffness will slide first - ALWAYS!
This is why many people add a stiffer rear roll bar, as it will REDUCE understeer and "feel" better. I hope they have the skill to "catch" the car when the rear wants to be in the front - oversteer can bite you in the A$$.
With any mod, be careful when "testing out" the new modification.
In my opinion the "Sport" suspension in the G37 is FANTASTIC and much better than most stock vehicles.
Now if you have money burning a hole in your pocket, look at getting an intake or exhaust. OR better yet, sign up for a high performance driving school
)I already have a cold air intake and hfc's installed which is why I wanted to do something to upgrade handling.
So as long as I dont try driving hard in the rain and have good tires my rear wont try to be in the front? (Some friends want to do a canyon run and got the sway bars to help with that so want to make sure nothing drifts out)
I already have a cold air intake and hfc's installed which is why I wanted to do something to upgrade handling.
)I already have a cold air intake and hfc's installed which is why I wanted to do something to upgrade handling.
Wow, I don't want to start a huge argument but there is a lot of bad info in this thread.
This guy knows what he is talking about, you'd do well to listen to him. Once you start going to motorsport and start increasing spring rates, a lot of the fastest Z/G cars and drivers run NO rear sway bar.
Increasing roll stiffness INCREASES the weight on the inside wheel by REDUCING weight transfer, which in turn increases total grip available to the car. This is good when traction is high and as traction reduces the typical first thing to do is reduce roll stiffness (softer sway bars) as the additional weight transfer can help the much lower grip on the outside tyres. As always, there is a sweet spot depending on chassis dynamics. For a G, a stiffer front sway bar and stock on the rear is about perfect.
Either way, whatever you like is just fine, but if you want to go fast on a track the Hotchkis front and stock rear is 95% of the correct answer. If you are just going to play on the road, stay on stock and/or not sticky tires then go with whatever you want and prefer as now it's mostly irrelevant.
Increasing roll stiffness INCREASES the weight on the inside wheel by REDUCING weight transfer, which in turn increases total grip available to the car. This is good when traction is high and as traction reduces the typical first thing to do is reduce roll stiffness (softer sway bars) as the additional weight transfer can help the much lower grip on the outside tyres. As always, there is a sweet spot depending on chassis dynamics. For a G, a stiffer front sway bar and stock on the rear is about perfect.
Either way, whatever you like is just fine, but if you want to go fast on a track the Hotchkis front and stock rear is 95% of the correct answer. If you are just going to play on the road, stay on stock and/or not sticky tires then go with whatever you want and prefer as now it's mostly irrelevant.
Last edited by Splitter; Jan 5, 2017 at 09:15 AM.
My advice is simple: aftermarket swaybars reduce body roll, all but eliminate understeer, and are a significant improvement over the stock parts on the RWD Sport Sedan; (and I assume the Coupe as well). All of those statements are more like facts than opinions, but you could argue that statement in of itself is an opinion, so...
As to the how and why of the physics... don't care. Racecar.
Here's some good info:
https://www.myg37.com/forums/brakes-...ml#post3337409
https://www.myg37.com/forums/brakes-...ml#post3337409
3. Transfer lateral grip from one end of the car to the other.
This one is a real trick to understand, but racers exploit this EVERY time they go
on the track. Their spring rates are often so high, the cars so low, and their
suspension travel so little, that the whole camber and body lean problem is already
a non-issue. The car doesn't lean much with 500 lb springs. They use their bars
to change the balance of the car. Here's the simple rules first.
A big bar on the front, increases rear lateral and motive traction.
A big bar on the rear, increases front lateral and motive traction.
The applications. If the car is understeering, decrease front bar size, or increase
rear bar size. This increases front lateral grip and decreases rear lateral grip
giving the car a more neutral to oversteer feel. Reverse the process for
too much oversteer.
I mentioned motive grip. That's the neat one. Let's say your RWD car is handling ok, but
everytime you get into a corner hard and get on the gas the rear inside tire breaks loose
and spins. You can't accelerate out of the turn. You can go around the turn quite
quickly, but you can't accelerate out, and the guy with traction hooks up and
passes you halfway down the next straight because he came out of the turn going 3-4mph faster.
The reason you're losing the traction at the inside rear, is usually because the rear bar is too big.
As the rear outside suspension compresses, it's actually causing the rear inside suspension to
compress as well (because the bar couples the sides.. remember where we started), and that
decreases the weight on the rear inside tire.
First thing. Decrease size of rear bar. That decouples the sides a bit, let's the inside tire press
down on the road more and thus not spin when you're on the gas.
Here's where it gets really tricky.
If decreasing the size of the rear bar doesn't help enough the next thing you do is
increase the size of the front bar. When the outside front compresses in a corner, it
causes the inside front to compress and may actually lift that tire completely off the
ground. The car is now sitting on 3 tires and guess where the weight that was on
the inside front goes? Outside front? Some of it. The rest goes to the inside rear
where we need more grip. The total weight of the car hasn't changed. It's just been
redistributed, and a sway bar at one end, actually transfered weight to the other
end of the car.
This one is a real trick to understand, but racers exploit this EVERY time they go
on the track. Their spring rates are often so high, the cars so low, and their
suspension travel so little, that the whole camber and body lean problem is already
a non-issue. The car doesn't lean much with 500 lb springs. They use their bars
to change the balance of the car. Here's the simple rules first.
A big bar on the front, increases rear lateral and motive traction.
A big bar on the rear, increases front lateral and motive traction.
The applications. If the car is understeering, decrease front bar size, or increase
rear bar size. This increases front lateral grip and decreases rear lateral grip
giving the car a more neutral to oversteer feel. Reverse the process for
too much oversteer.
I mentioned motive grip. That's the neat one. Let's say your RWD car is handling ok, but
everytime you get into a corner hard and get on the gas the rear inside tire breaks loose
and spins. You can't accelerate out of the turn. You can go around the turn quite
quickly, but you can't accelerate out, and the guy with traction hooks up and
passes you halfway down the next straight because he came out of the turn going 3-4mph faster.
The reason you're losing the traction at the inside rear, is usually because the rear bar is too big.
As the rear outside suspension compresses, it's actually causing the rear inside suspension to
compress as well (because the bar couples the sides.. remember where we started), and that
decreases the weight on the rear inside tire.
First thing. Decrease size of rear bar. That decouples the sides a bit, let's the inside tire press
down on the road more and thus not spin when you're on the gas.
Here's where it gets really tricky.
If decreasing the size of the rear bar doesn't help enough the next thing you do is
increase the size of the front bar. When the outside front compresses in a corner, it
causes the inside front to compress and may actually lift that tire completely off the
ground. The car is now sitting on 3 tires and guess where the weight that was on
the inside front goes? Outside front? Some of it. The rest goes to the inside rear
where we need more grip. The total weight of the car hasn't changed. It's just been
redistributed, and a sway bar at one end, actually transfered weight to the other
end of the car.
