You actually need a lot more spring, but since it appears yours is a street car I would go full stiff on the front bar first and see how that works. Also, increase front track width with spacers. It looks like you have enough room to add at least a 1/2" spacer on each front wheel.

You might also want to raise the car up a bit. If your roll centers are underground you're not getting much geometric roll resistance out of the suspension.

 

Yeah I guess that would help?

Ohlin PCV
10Kg/mm Front and 7Kg/mm Rear

 

I'd bump the spring rate up....the bar on full stiff will help with roll rate a bit in the mean time, though.

+1 on what beta said as well.

 

It is my street car, mainly on street to get to the track lately until I have room for a trailer at my house.

Are spacers recommended for track use? I always frowned upon them.

The car isn't slammed my any means, when I installed the Coilovers the car lost about an inch of clearance.

 

Really eh, I just bought this setup too

 

I use ARP studs and billet slip on spacers....never had an issue.

 

Cool. Thanks for the input.

 

I don't know how the ohlins are valved, but as long as you know the ID, spring length, and rate you want......you can get them fairly cheap. Eibach ERS are ~$55 a spring.

 

What about increasing spring preload?

 

What is recommended for my scenario? 12K/10K?

 

Might be worth calling ohlins or one of their vendors for input....I don't know anything about the valving on them.

 

Just to give you an idea of my setting (i'm not a pro by any means) i run a 12.4k front and 5k rear (equal to 10k in factory bucket) and maybe lowered 20mm (probably less) 275/35 front and 275/40 rears NT05 cause yes tires do make a difference in spring selection and my Hotchkis sways are set to full soft rear and staggered between med hard and med soft up front (4 hole front bar)
Pics from my last track day show minimal body roll. When i get home, i'll see if i can find a couple.
Spacers, why not, just run proper studs. Plenty people run quality spacers with studs on the track.

 

Thanks for the input, I'm not going to run out and buy new springs....yet.

I'll tinker around with everything this season and go from there.

I believe my front spring is ID65 H200 and 100N/mm

I see SPL carries a Swift 65, 203, 12Kg.

That might work later on.

 

+1 on the ride height, that coupled with the tire size seems a little off.

For right now, spring changes might be a little extreme assuming your needs and uses. However, I don't think Ohlins spec'ed the setup for that drop.

Do you have a static pic to get a idea of how low you really are?

Do you have anyone in the area that can do a corner balance/ride height adjustment for you if you can't sort it out yourself?

What size tires are you on?

 

Yeah I run 275/40/17 at the rack, so it definitely makes it look worse than it is.

I run OEM 18" on the street.

IIRC height is set at close to what Ohlin recommended in their install documentation. I think it was 33mm between spring perch adjuster and heigh adjuster. Maybe even more because there is about 4-5mm of preload on the spring.

The rear of my car is gutted, so another contributing factor could be less weight in the rear making the front heavier.

I've looked around locally for corner balancing but have come up short. I may have to take a trip to get it done, I feel like that could really help my issue.

 

From the manual;

 

What kind of tires are you running? Next, you also have the weight of your turbo kit up front (probably close to 100 pounds) Last, how much are you actually dropped?

 

That day was slick nt-01's
True, I have the TT and everything surrounding it up front as well.

I didn't measure what the OEM height of a G35 was prior to install, but I know with my 18" wheels on, the top of my wheel well fender is 26.5" from ground in front, and roughly 27" in rear.

 

That just reduces initial sag and has no affect on rate.


No. Less weight is less weight. You may have increased your front percent but the car still weighs less, including the front.

Another issue could be driving style. Coming into the corner hard with a lot of trail braking will load the outside front. Is that a problem? Lap times and tire temps will answer that.

 

Actually you could be right, I could just be over analysing for nothing.

This is the corner (multiple corners taken as 1), there is ALOT of load at the front left at this point in order to setup the car for exit.

In the image attached, those pictures are taken at entry/exit of 18-19.