Erik W. Treves
12-13-2021, 09:35 AM
The last two events of the local SCCA Solo 2 season were super fun and I got the bug again. With my GTM stuck at paint and some time on my hands I decided to see how the Hawk was now after 4 and half years. The last event was wet so that was interesting – but during the first event I went to somebody took some action pictures of the car…. Wow there was quite a bit of roll in the car. This picture sorta made sense with what I think I am feeling and maybe what the car needs….There is obviously way more performance in the car that I have skill – but I think I needed some help…. The car is fine in my mind in steady state, but does dive a bit in braking. Also during direction changes the car “feels” like it “jumps” off the side it’s on… then out of the turn it’s loses traction - this is definitely me and managing the HP I have –
When I set up the car – now 4.5 years ago – I had to increase the rear spring rates a little to keep the rear end from diving under hard acceleration with 2 people in it… the 335’s were contacting the frame… when I did this, during the first autox checkout I did the car was very loose… so I immediately disconnected the rear sway bar and things were all neutral…. still learning the car at the time with very little seat time… Fast forward – I am a ton more aggressive with the car now and understand the characteristics of managing 700+ hp on the street and limited track settings…. sooooooo….. so small changes needed – none of these will get me to FTD – but should allow the next step of learning to occur.
I took ride height measurements and front suspension camber settings prior to the change: 4 inch rear / 3.25 front and 1.4 * camber. I also verified that all shocks were in fact in position zero before making any changes.
The Change:
Set the car up with 3.5 front ride height which gave me 1.0-1.1 camber – we will see how much the springs relax and then decide – tire wear at the previous setting showed equal tire ware across the tire so 1.4* wasn’t eating tires…. although I am going through rear tires on a 3 to 1 ratio.
Front springs were 500 lbs – so I went to 600 lbs –
Front Koni adjusted to 50% rebound stiffness (2 clicks)
Rear Koni adjusted to 20% stiffness (1 click)
On the fronts I took the shocks completely out of the car – counted the turns on the adjustment collar and removed the spring to make the adjustment and changed the spring.
When I moved to the rear all I did was disconnect the top of the shock – leaned it out and made the change right there on the car using the same procedure for spring removal.
The whole task took 3.0 hours to include setting corner weights and ride height.
https://thefactoryfiveforum.com/attachment.php?attachmentid=158565&d=1639405863
https://thefactoryfiveforum.com/attachment.php?attachmentid=158566&d=1639405863
https://thefactoryfiveforum.com/attachment.php?attachmentid=158567&d=1639405863
https://thefactoryfiveforum.com/attachment.php?attachmentid=158568&d=1639405863
Immediately after this change I went out for a quick shake down and to make sure the springs get settled… I believe the biggest change I felt were the Koni adjustments – the car felt a lot more in the road and the car reacted a lot quicker to steering input without roll… the ride a touch firmer but not at all uncomfortable … since I changed what the weight transfer characteristics were, I did a few hard braking tests – the rears were locking up way too early!! not good…. I cranked on the bias adjuster knob for days – no change… very frustrating - got back to the garage and inspection of the adjustment cable revealed that the cable was broken and no adjustment were being made…. disconnected the cable - made the manual adjustment – the fronts now lock up before rears and I can get all 4 to slide (new tires are coming so really don’t care about flat spots)
Anyway – very long post – but this also acts as my logbook if I forget what I did – so I can find this post later…. handy tool….anyway – I am hopefully gonna spend more time at the local track next year – in the mean time the car really is a lot nicer to drive (for me) – It was already riding well – but man – big difference – the car is way more “in the road”….. nice to have that flexibility already built into the design!!!
When I set up the car – now 4.5 years ago – I had to increase the rear spring rates a little to keep the rear end from diving under hard acceleration with 2 people in it… the 335’s were contacting the frame… when I did this, during the first autox checkout I did the car was very loose… so I immediately disconnected the rear sway bar and things were all neutral…. still learning the car at the time with very little seat time… Fast forward – I am a ton more aggressive with the car now and understand the characteristics of managing 700+ hp on the street and limited track settings…. sooooooo….. so small changes needed – none of these will get me to FTD – but should allow the next step of learning to occur.
I took ride height measurements and front suspension camber settings prior to the change: 4 inch rear / 3.25 front and 1.4 * camber. I also verified that all shocks were in fact in position zero before making any changes.
The Change:
Set the car up with 3.5 front ride height which gave me 1.0-1.1 camber – we will see how much the springs relax and then decide – tire wear at the previous setting showed equal tire ware across the tire so 1.4* wasn’t eating tires…. although I am going through rear tires on a 3 to 1 ratio.
Front springs were 500 lbs – so I went to 600 lbs –
Front Koni adjusted to 50% rebound stiffness (2 clicks)
Rear Koni adjusted to 20% stiffness (1 click)
On the fronts I took the shocks completely out of the car – counted the turns on the adjustment collar and removed the spring to make the adjustment and changed the spring.
When I moved to the rear all I did was disconnect the top of the shock – leaned it out and made the change right there on the car using the same procedure for spring removal.
The whole task took 3.0 hours to include setting corner weights and ride height.
https://thefactoryfiveforum.com/attachment.php?attachmentid=158565&d=1639405863
https://thefactoryfiveforum.com/attachment.php?attachmentid=158566&d=1639405863
https://thefactoryfiveforum.com/attachment.php?attachmentid=158567&d=1639405863
https://thefactoryfiveforum.com/attachment.php?attachmentid=158568&d=1639405863
Immediately after this change I went out for a quick shake down and to make sure the springs get settled… I believe the biggest change I felt were the Koni adjustments – the car felt a lot more in the road and the car reacted a lot quicker to steering input without roll… the ride a touch firmer but not at all uncomfortable … since I changed what the weight transfer characteristics were, I did a few hard braking tests – the rears were locking up way too early!! not good…. I cranked on the bias adjuster knob for days – no change… very frustrating - got back to the garage and inspection of the adjustment cable revealed that the cable was broken and no adjustment were being made…. disconnected the cable - made the manual adjustment – the fronts now lock up before rears and I can get all 4 to slide (new tires are coming so really don’t care about flat spots)
Anyway – very long post – but this also acts as my logbook if I forget what I did – so I can find this post later…. handy tool….anyway – I am hopefully gonna spend more time at the local track next year – in the mean time the car really is a lot nicer to drive (for me) – It was already riding well – but man – big difference – the car is way more “in the road”….. nice to have that flexibility already built into the design!!!