Coilovers vs conventional Koni P spring combo

[Mad Hatter]

I am planning next years upgrades and budget, can some one give me an idea of what kind of improvement in track times you can get by upgrading to a set of track oriented coilovers (Cortex, MM etc) vs a set of Koni Yellows and P springs ?? A set of coil overs will put a big dent in my tire budget! Wanted to know if would be worth it. Track events are all Time Attack style with 10min sessions on 1.6km to 2.7km tracks. Will be using 295/30-18 Dunlop DZ03G semislicks since I get a steep local discount here in Chile.

 

[VoodooBoss]

Hopefully BlackBoss will provide some comments on his recent upgrade.

Coilovers by themselves won't make you faster. What quality dampers will do is give you more control over your car which enables you to drive at the edge with more control and consistency. They will have the ability to adjust the ride height and have more adjustablity to stiffen or soften the dampers. This allows you the ability to stay at the edge under various track conditions. They are also rebuildable and you can have them revalved to meet your specific needs.

http://blog.hancheyvehicletech.com/hvt-damper-analysis-report-definitions-and-damper-101/

 

[steveespo]

Coil overs allow the freedom of more readily available higher spring rates. Conventional springs for the S197 platform seem to max out at 335 lb/in, with 2.5" coil overs there are many manufacturers that can provide springs from 200lb. to 2000lb. and varying spring lengths. I have gone from P springs with rates of 225 Front/185 Rear to 600 F/375 R. The more advanced dampers are able to control the power of these spring rates where even a good aftermarket strut/shock from koni or Bilstein will not. To go really fast this platform needs spring rate, if you add big wing/splitter/downforce even more so. It all depends what you are looking to do with the car, full track and competitive=coil over, occasional track/street= Conventional spring/shocks. Coil over setups will be quicker, how much depends on the driver.
Steve

 

[Black Boss]

Hopefully BlackBoss will provide some comments on his recent upgrade.

Coilovers by themselves won't make you faster. What quality dampers will do is give you more control over your car which enables you to drive at the edge with more control and consistency. They will have the ability to adjust the ride height and have more adjustablity to stiffen or soften the dampers. This allows you the ability to stay at the edge under various track conditions. They are also rebuildable and you can have them revalved to meet your specific needs.

http://blog.hancheyvehicletech.com/hvt-damper-analysis-report-definitions-and-damper-101/

I switched from the basic LS suspension to coilovers last season with 600/350# springs. Lap times have improved, but as Rick points out I'm now way more comfortable driving closer to the limit -- the car is way more predictable, and my consistency has improved a lot lap to lap. With the original set up, I'd put in a good lap and not match it.

For outright lap times, I found tires to make the biggest improvements. For consistency and the ability to tune in, Coilovers. I wouldn't go back, the car is just more fun......

 

[Mad Hatter]

Thanks, more or less what I wanted to know!! Still drive the car to the track so will probably go with the Cortex Street kit with 425#F and 250#R springs. My friend has just installed his Cortex Extreme race kit with the Konis, will see first hand how he does with our season finally on the 28th.

Do you find the ability to corner balance the car a plus or mainly the increased control of higher spring rates?

Will put the tires ahead as my number one item.

 

[VoodooBoss]

Do you find the ability to corner balance the car a plus or mainly the increased control of higher spring rates?

You'll need adjustable sway bar links to corner balance your car.

 

[Mad Hatter]

hmm, good point.... Can you corner balance if you disconnect the sway bars?

 

[VoodooBoss]

I'm no expert on this but I'm sure you can. But then reattaching the sway bar could potentially disrupt the balance.

 

[Black Boss]

I'm no expert on this but I'm sure you can. But then reattaching the sway bar could potentially disrupt the balance.

True. You need adjustable links to achieve full balance. I'm running a super thin bar at the rear, from Watson which comes with adjustable links, and I bought the Watson adjustables for the fronts which I'm using with the FRPP bar.

Never ran the car without corner balancing on coilovers, but it's got to help with consistency.....

 

[Swiss Boss]

Thanks, more or less what I wanted to know!! Still drive the car to the track so will probably go with the Cortex Street kit with 425#F and 250#R springs. My friend has just installed his Cortex Extreme race kit with the Konis, will see first hand how he does with our season finally on the 28th.

Do you find the ability to corner balance the car a plus or mainly the increased control of higher spring rates?

Will put the tires ahead as my number one item.

You will probably need more spring than that with your tire. It seems 550-660F and around 250R for stock location or 300-350R for coil over, is the best choice.

I have 550F and 250R on the MCS and with the shocks all the way down it rides better than the P spring. Unless I hit a pothole or bump stop at speed.

More adjustment possibilities for corner balancing=less compromise you have to make

 

[2012-Boss]

True. You need adjustable links to achieve full balance. I'm running a super thin bar at the rear, from Watson which comes with adjustable links, and I bought the Watson adjustables for the fronts which I'm using with the FRPP bar.

Never ran the car without corner balancing on coilovers, but it's got to help with consistency.....

Are you running the front bar in the middle or full stiff position?

 

[Black Boss]

Are you running the front bar in the middle or full stiff position?

Am running in the mid position.

 

[VoodooBoss]

More info on the JRi's.

http://www.lateral-g.net/forums/showpost.php4?p=561557&postcount=361

 

[steveespo]

Great info Rick. I knew JRi was a premier brand, glad to know it is eye to eye or above Penske's
Steve

 

[Mad Hatter]

You will probably need more spring than that with your tire. It seems 550-660F and around 250R for stock location or 300-350R for coil over, is the best choice.

I have 550F and 250R on the MCS and with the shocks all the way down it rides better than the P spring. Unless I hit a pothole or bump stop at speed.

More adjustment possibilities for corner balancing=less compromise you have to make

Your right, I was very surprised, got a ride in my buddies GT with the full race cortex koni setup, 600#F and 450#R spring rates. The ride included several rail lines.... the ride was far more refined then I ever imagined it could be. For a 50% track car, more then enough for street use

 

[Mad Hatter]

Cortex coil overs are installed and I get to try them out on the track on Sunday. So far its great to raise the car a tad and not bottom out on all the speed bumps. Ride is fine on the street. The P springs where fine at first but the settled to much for daily use after a year.

 

[Grant 302]

Cool. Looking forward to your update after you run.

 

[DGRacing]

There is definitely an interplay between spring rate of coil springs, tires and other components. If you go to a performance coil over with high spring rate you should be running a very sticky R tire or DOT slick at minimum. Once you're able to keep the chassis controlled and are able to increase speed tires become weak link quickly. It works both ways. If you run a slick on a weak spring rate the extra Gs are gonna tax that suspension making it slower in some cases.
Everything plays a role in how quickly the car can absorb Gs and change direction. And you will quickly discover the weak link in the system as you upgrade components. But when those weak spots have been addressed large gains are available.