Coilover suspension recommendations for a wide body w/ Forced Induction

[Bd792010]

Hey guys looking to change up my suspension and wanted to get some input. Currently on Ground Control Suspension with KONI struts paired with 6.7k (375) 6 inch springs in the front and 6.3k (350) 7 inch springs in the rear. When going over small bumps I’m having issues with clanking/unsettling in the rear and occasional rubbing up front at full lock. The rubbing typically only happens after I leave the car parked in a position for an extended period of time and the springs settle. There is no preload on the springs at full droop in the rear so I assume I need helper springs?

Regardless I think my current suspension setup is a bit too soft. When contacting Ground Control Suspension they recommended switching to either a 500/550 setup or 600/650 spring rate setup. I’m also not sure if this would require me to re-valve my dampers. Considering switching to Fortune Auto 500 Coilovers and they suggested 7-8k front and 8-9k rear.

I’m currently running a Rallybacker v1 wide body setup with 18x9.5” +5 wheels in the front w/ 255/40/18 and 18x10.5” -20 in the rear w/ 285/35/18 on General G Max tires. Along with this I also have a c38 Jackson Racing supercharger installed. I plan on mainly driving my car on the street with an occasional track day or HPDE each year.

I’m not familiar with suspension tuning so any advice or suggestions are greatly appreciated. Not sure if I should just swap out for more aggressive springs and stick with my current setup or if I should just switch entirely.

[Racecomp Engineering]

Why do you think your suspension is too soft for a mainly street car? Just asking.

- Andrew

[Soloside]

Originally Posted by Racecomp Engineering

Why do you think your suspension is too soft for a mainly street car? Just asking.

- Andrew

I think can answer that for you since I know what brandon's thinking (local guy to me so i'm not pulling random shit out of my ass)

He wants to keep his car at current ride height and try to eliminate some of the bottoming out/rubbing that happens while just driving on piss poor eastern PA roads.

[Racecomp Engineering]

Originally Posted by Soloside

I think can answer that for you since I know what brandon's thinking (local guy to me so i'm not pulling random shit out of my ass)

He wants to keep his car at current ride height and try to eliminate some of the bottoming out/rubbing that happens while just driving on piss poor eastern PA roads.

Gotcha. Definitely sounds like the current suspension is not working.

Adequate travel, spring length, and set up are crucial for any set up. Is the car really low?

- Andrew

[Soloside]

Originally Posted by Racecomp Engineering

Gotcha. Definitely sounds like the current suspension is not working.

Adequate travel, spring length, and set up are crucial for any set up. Is the car really low? I want to say he only has at most 2 fingers gap between wheel and fenders.

- Andrew

The rallybacker v1 kit naturally sits REALLY low if you have to minimize the wheel gap. I'll link his pictures below

https://www.instagram.com/diced_brz/


On another note,

Thanks for answering my questions when I called a while back. I ended up getting my stiffer springs from you guys to solve the issue he's having troubles with. Went with 9ks all around on my KWv3s (Pretty sure it's at the maximum spring rate for it's valving)

[Bd792010]

Originally Posted by Racecomp Engineering

Gotcha. Definitely sounds like the current suspension is not working.

Adequate travel, spring length, and set up are crucial for any set up. Is the car really low?

- Andrew

Everything he said was accurate. Do you have any thoughts or suggestions?

[HaXx]

im going rallyback v2 soon on a s/c brz, and in anticipation, i put in 9k/8k FA 500 coils and SPL rlca. i think 9k/8k is great for daily, ive had it on for a month or two and as far as comfort and ride quality, no complaints.

[Bd792010]

Originally Posted by HaXx

im going rallyback v2 soon on a s/c brz, and in anticipation, i put in 9k/8k FA 500 coils and SPL rlca. i think 9k/8k is great for daily, ive had it on for a month or two and as far as comfort and ride quality, no complaints.

What made you decide on the stiffer springs up front?

[HaXx]

Originally Posted by Bd792010

What made you decide on the stiffer springs up front?

i bought second hand coils from this forum that had 5k miles on them for 50% price. thats just what they were, but typically you do see a tad stiffer front, sometimes you do, sometimes you dont, not sure why.

[Racecomp Engineering]

Originally Posted by Bd792010

Everything he said was accurate. Do you have any thoughts or suggestions?

You don't need really high spring rates if you have adequate travel and aren't worried about rubbing. Our RCE SS1s use lowering camber plates in front and have a lot of compression and droop travel. Spring rates are 6 kg/mm front and rear, which is great for the street. A 1.5 inch drop from stock is easy.

If you want to go much lower, something like Fortune Auto would do the trick. Not as much total travel but it will let you get lower. They might require stiffer springs though.

- Andrew