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Discussion Starter · #1 · (Edited)
Dear Friends,

What follows below may fly in the face of reason, enlighten, or even entertain.

OCD QV Part 1 Problem Statement

“The handling and steering of the Giulia QV is wanting at best and surprises to the downside given the intended use of the car. Little to no camber in front (-0.5 deg). No feel, nervous, oversteer turn in feel, constant correction in mid to higher speed sweepers. Great for parking the car in town though.”

How can this be? How to cure the ills?

To solve this perceived issue I consulted with a suspension engineer friend with over 30 years combined race and road car experience at Ford, Rahal Racing, Multimatic, Turner Racing, and others. Jay set up my last car, a Porsche GT4, and that car was extremely predictable and fun to drive, and featured multi-link rear suspension designed by him.

One possible reason for perceived steering/handling issues, to quote: "Alfa likely reduced the Giulia trail and scrub radius so as to reduce torque steer in the 4WD models. Unfortunately, the makes the RWD QV steering efforts too low.” Therefore, the Giulia front suspension was likely engineered to also be used in 4WD cars and Stelvio SUV for efficiency /cost savings and therein is compromised.

To initiate the project, “OCD QV Part 1”, Jay dropped by my house on the way to Laguna, took some measurements, ordered front suspension parts of eBay and put them in CAD.

Proposed Solutions

  1. Increase track width via a square set-up (10” F & R with associated spacers) for more front end bite and stability and footprint
  2. Increase scrub radius for more steering effort and feel
  3. Increase camber for more contact patch in performance driving (inc. to -2.8 deg for track use)
  4. Keep caster same
How it is done
  • Obtain O'Connell Car Development (OCD) adjustable upper control arms/wishbones. The adjustable upper control arms suck in the top of the wheel/tire and provide clearance for the larger wheel, so it won't hit the fender and will increase camber. See pictures
  • Obtain 10 " wide wheels such as Technicos (thanks to Jason at Alfissimo)
  • Obtain 285 width tires (Tire Rack)
  • Obtain longer lug nuts (thanks to Jason at Alfissimo)
  • Obtain 17 mm spacers (thanks to Jason at Alfissimo)

NOTE: Other camber kits on the market will not allow for the fitting of the larger wheels in front nor the change in steering feel and/or self centering character that the OCD mods achieve.

Results

  • The steering effort and weight in “n” mode is like that of “d” and “race”. That is because of the increased scrub radius
  • The steering now has self centering character and is not jittery
  • The traction and bite “feels” very much more substantial through the wheel, it helps to have 10 “ and 285 in front
  • The car feels very stable due to the increased +20 mm track width
  • I tested the set-up with the stock 9 “ wide wheels, the same effect was observed, but lessened due to the smaller wheel
  • With the 10 " 285 set-up there is slight front fender LINER rubbing at FULL lock. Removing a few fins from the liner eliminates most of the rubbing.
Detailed Technical Explanation

"The combination of the 17 mm thick wheel spacers and 10” wide QV rear wheels on the front axle increases the front scrub radius by 10 mm, the front track width by 20 mm, and the overall front width at the ground by 58 mm. The +10 mm scrub radius, the distance in the front view from the steering axis to the center of the tire at the ground, increases the torque around the steering axis which increases the tie-rod forces and thereby the steering feel. The increased steering feel is noticeable all the time with the larger scrub radius since the aligning torque around the steering axis is higher when driving. The larger scrub increases the self-centering forces when the wheels are turned due to the larger moment arm. The +20 mm track width reduces understeer by reducing lateral weight transfer when cornering, and by jacking more weight onto the inside front wheel (and outside rear wheel) when turned due to the longer lever arm between the steering axis and the center of the wheel."

For those interested in obtaining the kit and all alignment metrics, please PM me.

Next stop is Laguna Seca after brakes are done in “OCD QV Part 2”. We also plan to increase the trail.

Regards to all,

TC
 

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2018 Giulia Ti Sport Q4
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THAT'S WHAT I'M TALKING ABOUT! Upper a-arms are the key. Thank you for going down this path. No more bullshit shim kits.
 

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Discussion Starter · #5 ·
My car is still on stock springs, not lowered. I think that the ride is quite compliant in spirited street driving.

For those cars that are lowered, OCD will provide a correct setting to achieve the desired camber.
 

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THAT'S WHAT I'M TALKING ABOUT! Upper a-arms are the key. Thank you for going down this path. No more bullshit shim kits.
Well, I would not call ours a bullshit shim kit.

This is a great solution for DIY guys with CNC machines and skills at their disposal. The problem I see in terms of offering such solution publicly is, that OEM control arms must be cut and then threaded to fit spherical joints. This requires CNC machine to do it properly. Also with a single thread design like this, the entire ball joint must be rotated to adjust its length (camber), so it’s not the most user friendly to adjust.

Adding a few shims underneath to adjust camber is much easier than rotating entire spherical joint and removing upper control arm each time (on both sides of attachment to the chassis). I still believe that our camber / caster kit is currently the best bang for buck upgrade available for spirited drivers and track fellas. This set up is fantastic but again it's not user friendly for most and labor intensive.
 

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2018 Giulia Ti Sport Q4
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Well, I would not call ours a bullshit shim kit.

This is a great solution for DIY guys with CNC machines and skills at their disposal. The problem I see in terms of offering such solution publicly is, that OEM control arms must be cut and then threaded to fit spherical joints. This requires CNC machine to do it properly. Also with a single thread design like this, the entire ball joint must be rotated to adjust its length (camber), so it’s not the most user friendly to adjust.

Adding a few shims underneath to adjust camber is much easier than rotating entire spherical joint and removing upper control arm each time (on both sides of attachment to the chassis). I still believe that our camber / caster kit is currently the best bang for buck upgrade available for spirited drivers and track fellas. This set up is fantastic but again it's not user friendly for most and labor intensive.
That is a quality product, don't get me wrong, but it's not the best (or complete) solution IMO. Adjustable UCA along with that kit would be great, especially once you start lowering the vehicle. I think that the ride height plays into the ability of that GMS kit to actually alter the camber. Some people saw great results while others not so much, and I think the height was the problem.
 

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That is a quality product, don't get me wrong, but it's not the best (or complete) solution IMO. Adjustable UCA along with that kit would be great, especially once you start lowering the vehicle. I think that the ride height plays into the ability of that GMS kit to actually alter the camber. Some people saw great results while others not so much, and I think the height was the problem.
Again the UCA if sold with the kit for example, already done would be very expensive and not sell well. If this was a 4C it would sell well but it's not. Very few would opt for a kit that costs more than the GMS kit which essentially does a fantastic job at getting you negative camber and adjust caster if needed. Doing the UCA yourself requires some work and adjustability won't be easy for most. Our kit is used on the track all the time. Many are using it now. Stock height (17 springs referring to) can achieve a nice negative camber with the use of a few shims. Much easier solution for 99% of owners wanting better handling, tire wear and so forth. ;) The solution above is another option if you have the means.
 

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2018 Giulia Ti Sport Q4
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Again the UCA if sold with the kit for example, already done would be very expensive and not sell well. If this was a 4C it would sell well but it's not. Very few would opt for a kit that costs more than the GMS kit which essentially does a fantastic job at getting you negative camber and adjust caster if needed. Doing the UCA yourself requires some work and adjustability won't be easy for most. Our kit is used on the track all the time. Many are using it now. Stock height (17 springs referring to) can achieve a nice negative camber with the use of a few shims. Much easier solution for 99% of owners wanting better handling, tire wear and so forth. ;) The solution above is another option if you have the means.
People buy carbon fiber covers for their mirrors.

I rest my case.
 

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LOL
 
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Dear Friends,

What follows below may fly in the face of reason, enlighten, or even entertain.

OCD QV Part 1 Problem Statement

“The handling and steering of the Giulia QV is wanting at best and surprises to the downside given the intended use of the car. Little to know camber in front (-0.5 deg). No feel, nervous, oversteer turn in feel, constant correction in mid to higher speed sweepers. Great for parking the car in town though.”

How can this be? How to cure the ills?

To solve this perceived issue I consulted with a suspension engineer friend with over 30 years combined race and road car experience at Ford, Rahal Racing, Multimatic, Turner Racing, and others. Jay set up my last car, a Porsche GT4, and that car was extremely predictable and fun to drive, and featured multi-link rear suspension designed by him.

One possible reason for perceived steering/handling issues, to quote: "Alfa likely reduced the Giulia trail and scrub radius so as to reduce torque steer in the 4WD models. Unfortunately, the makes the RWD QV steering efforts too low.” Therefore, the Giulia front suspension was likely engineered to also be used in 4WD cars and Stelvio SUV for efficiency /cost savings and therein is compromised.

To initiate the project, “OCD QV Part 1”, Jay dropped by my house on the way to Laguna, took some measurements, ordered front suspension parts of eBay and put them in CAD.

Proposed Solutions

  1. Increase track width via a square set-up (10” F & R with associated spacers) for more front end bite and stability and footprint
  2. Increase scrub radius for more steering effort and feel
  3. Increase camber for more contact patch in performance driving (inc. to -2.8 deg for track use)
  4. Keep caster same
How it is done
  • Obtain O'Connell Car Development (OCD) adjustable upper control arms/wishbones. The adjustable upper control arms suck in the top of the wheel/tire and provide clearance for the larger wheel, so it won't hit the fender and will increase camber. See pictures
  • Obtain 10 " wide wheels such as Technicos (thanks to Jason at Alfissimo)
  • Obtain 285 width tires (Tire Rack)
  • Obtain longer lug nuts (thanks to Jason at Alfissimo)
  • Obtain 17 mm spacers (thanks to Jason at Alfissimo)

NOTE: Other camber kits on the market will not allow for the fitting of the larger wheels in front nor the change in steering feel and/or self centering character that the OCD mods achieve.

Results

  • The steering effort and weight in “n” mode is like that of “d” and “race”. That is because of the increased scrub radius
  • The steering now has self centering character and is not jittery
  • The traction and bite “feels” very much more substantial through the wheel, it helps to have 10 “ and 285 in front
  • The car feels very stable due to the increased +20 mm track width
  • I tested the set-up with the stock 9 “ wide wheels, the same effect was observed, but lessened due to the smaller wheel
  • With the 10 " 285 set-up there is slight front fender LINER rubbing at FULL lock. Removing a few fins from the liner eliminates most of the rubbing.
Detailed Technical Explanation

"The combination of the 17 mm thick wheel spacers and 10” wide QV rear wheels on the front axle increases the front scrub radius by 10 mm, the front track width by 20 mm, and the overall front width at the ground by 58 mm. The +10 mm scrub radius, the distance in the front view from the steering axis to the center of the tire at the ground, increases the torque around the steering axis which increases the tie-rod forces and thereby the steering feel. The increased steering feel is noticeable all the time with the larger scrub radius since the aligning torque around the steering axis is higher when driving. The larger scrub increases the self-centering forces when the wheels are turned due to the larger moment arm. The +20 mm track width reduces understeer by reducing lateral weight transfer when cornering, and by jacking more weight onto the inside front wheel (and outside rear wheel) when turned due to the longer lever arm between the steering axis and the center of the wheel."

For those interested in obtaining the kit and all alignment metrics, please PM me.

Next stop is Laguna Seca after brakes are done in “OCD QV Part 2”. We also plan to increase the trail.

Regards to all,

TC
wait a second, I see 245s in the front. Thought you said 285 would fit.
 

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Discussion Starter · #19 ·
Well, I would not call ours a bullshit shim kit.

This is a great solution for DIY guys with CNC machines and skills at their disposal. The problem I see in terms of offering such solution publicly is, that OEM control arms must be cut and then threaded to fit spherical joints. This requires CNC machine to do it properly. Also with a single thread design like this, the entire ball joint must be rotated to adjust its length (camber), so it’s not the most user friendly to adjust.

Adding a few shims underneath to adjust camber is much easier than rotating entire spherical joint and removing upper control arm each time (on both sides of attachment to the chassis). I still believe that our camber / caster kit is currently the best bang for buck upgrade available for spirited drivers and track fellas. This set up is fantastic but again it's not user friendly for most and labor intensive.
Yo Jason,

Don't mean to step on your fine product.

The OCD QV control arms require only a set stock control arms to be sent to and modified by OCD at their machine shop. Otherwise one can source from stealership.

Jay is doing a core program as well.

Best,

TC
 
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