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And I separated the car in 3 sections because they are easy to identify and to make some assumptions. in regards to their weight. In terms of development is important to split the car in 2 sections (in the middle between the wheels) and to find out how far away are the COG's from the center of the car. Because it's one thing to have a car with the engine right in the middle and one thing (like a BMW for example) with the engine on the front and some weight added on the rear end. Corner weighting would show the same on both cars.

I'm not stating that the spring rates you choose are wrong, I'm just saying that the rear of this car is very heavy and it's COG (of the rear end) is quite height. If tractive suspension will provide high performance on the race track (in this configuration of springs) I'm sure in the future we will see many cars going this route in the future. Everyone would like a comfortable suspension on the street and to be very capable on the racetrack.
 

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Discussion Starter #142
Why do you say is wrong? Because you assume that the rear section should weight 60% of the total weight? It doesn't work this way
Of course it does because the vehicle mass is a distributed load acting on four wheels, and each of those four loadings is measurable.
 

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Discussion Starter #143 (Edited)
I'm not stating that the spring rates you choose are wrong, I'm just saying that the rear of this car is very heavy and it's COG (of the rear end) is quite height. If tractive suspension will provide high performance on the race track (in this configuration of springs) I'm sure in the future we will see many cars going this route in the future. Everyone would like a comfortable suspension on the street and to be very capable on the racetrack.
I agree that a higher CoG affects roll, but the advantage of the Tractive setup is that accelerating forces are measured by the system and the appropriate damper is stiffened automatically when a load is measured, so in a steady state left hand corner the right hand dampers are stiffened and the left hand ones softened, hence hard springs aren’t required and traction is maintained, The dash mounted controller allows the driver to alter and limit (or allow) roll, and also (for example) stiffen the rear setup relative to the front. This can be done on the fly whilst driving.

Tractive also has a very clever system used by some Time Attack which uses GPS positioning to adjust the suspension automatically for individual corners, or soften it on straights allowing the car to lower itself.

I’m working with Raceshocks.UK and Tractive to develop a system that’s soft and comfortable when driving to the track, has a WRC-type compliance for mountain/canyon roads, and is capable on track. RaceShock.UK will be offering a number of setups for different requirements. Alipapa’s setup for example will be stiffer than mine and probably more capable on track.
 

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Of course it does because the vehicle mass is a distributed load acting on four wheels, and each of those four loadings is measurable.
With this statement you are wrong. If you want I can explain you in private with details so we don't alter too much this thread.
 

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I agree that a higher CoG affects roll, but the advantage of the Tractive setup is that accelerating forces are measured by the system and the appropriate damper is stiffened automatically when a load is measured, so in a steady state left hand corner the right hand dampers are stiffened and the left hand ones softened, hence hard springs aren’t required and traction is maintained, The dash mounted controller allows the driver to alter and limit (or allow) roll, and also (for example) stiffen the rear setup relative to the front. This can be done on the fly whilst driving.

Tractive also has a very clever system used by some Time Attack which uses GPS positioning to adjust the suspension automatically for individual corners, or soften it on straights allowing the car to lower itself.

I’m working with Raceshocks.UK and Tractive to develop a system that’s soft and comfortable when driving to the track, has a WRC-type compliance for mountain/canyon roads, and is capable on track. RaceShock.UK will be offering a number of setups for different requirements. Alipapa’s setup for example will be stiffer than mine and probably more capable on track.
I undertand how it's working and it has some great advantages over a non assisted suspension.

However, during a corner the car will eventually lean the same, the only limitation being the stiffness of the spring. The damper will smooth out that leaning / balancing effect and will help on stabilizing the car in this transition but it will compress the spring based on it's rate. If you install high grip semislicks or full slicks on the car, then the grip will be so high that the car will lean too much around corners and you will loose camber (the geometry on the rear can go to camber negative to camber positive easily) --> this in turn will make you loose grip.

On racetracks I would prefer much stiffer springs (especially on good surfaced tracks). Not to mention that I added aero on my car.

My posts are in no way meant to attack this product. I believe it is very good and has some advantages over a regular suspension. But I don't think on the racetrack this suspension (with these springs) would be superior to a normal suspension set up for the track (with considerably stiffer springs and dampers to match those spring rates). Of course, some tracks have only tight corners and bumpy surface, so a stiff suspension would not help. The high standards race tracks (part of the F1 championship) are very good and require a very stiff suspension.
 

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With this statement you are wrong. If you want I can explain you in private with details so we don't alter too much this thread.
On the scale you measure G1 and G2 but you don't know the actual weight of the front section of the vehicle and the rear section (Gf and Gr)
More important, you also don' know the application point of Gr (the rear center of gravity).
In a basic simulation, starting from a weight distribution of 40-60% you may discover that it is very plausible for the mass associated to Gf to be around 300 Kg and the one associated with Gr to be around 700 kg (it is just an estimation)
When the car is leaning around corners you take in consideration the centrifugal force determined by Gf and Gr. In addition to this, no matter how stiff the chassis is it will still flex so most of the Gr effect is transferred to the rear end.

When the car leans the front suspension is maintaining the camber (or increases the camber) but the rear is loosing camber (like in the second picture).
In the second picture you see the rear section and the car leaning with 2 and 5 degrees (for a normal and lowered suspension)






103495


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Discussion Starter #147
With this statement you are wrong. If you want I can explain you in private with details so we don't alter too much this thread.
Your arrogance clearly exceeds your (theoretical) knowledge. Why don’t you do something useful and re-read my stated requirements before you pollute this thread with your personal, irrelevant needs.
 

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Your arrogance clearly exceeds your (theoretical) knowledge. Why don’t you do something useful and re-read my stated requirements before you pollute this thread with your personal, irrelevant needs.
Ok, I apologize.
I will not post any more here.
 

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Your arrogance clearly exceeds your (theoretical) knowledge. Why don’t you do something useful and re-read my stated requirements before you pollute this thread with your personal, irrelevant needs.
Perhaps partially correct ... :) as sometimes knowledge expressed by someone not from your culture or trying to be precise in a language that may not be his native tongue, can come across this way. But from personal interactions with a number of members here, I can tell you that there is a great deal of engineering knowledge here. Take it or don't, as you wish. But please don't assume that since the direction of the discussion or the opinion points in a direction different from yours, that it is steeped in ignroance.

One somewhat related question which I have, and that the research into this product or the discussion above might have discovered - do we know the vertical CG of the car? I've seen it listed as 40cm off the ground, but question that.
 

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I made a bracket to mount the controller on top of the driver side AC vent. If it turns out working then I will post the drawing and detail. But I will definitely make a 3d printed mount for the long run.


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Your arrogance clearly exceeds your (theoretical) knowledge.
Its just sad to see words like that. I hope that you are able to be more constructive, or just ignore, next time you strongly disagree with someone. Conclude that you cannot agree with Cripsony is no problem, hostile words are.

However, I greatly appreciate that you share your experience with the product, keep it coming! That I'm interested is an understatement.....
 

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Got the system installed and drove home just now. The mount I made won't stick to the top of the AC vent, so I will stick it on the wind shield. I used all the softest setting at first to hopefully help the springs to settle, as the ride height is way too high at the recommended setting. The ride is much more comfortable than I thought, and it actully floated a little bit. I then turned everything all the way up and it was noticeable even going though highway connection. The biggest surprise to me was the picth setting. I used to scrub at the speed bump going into home garage, as the nose would pitch down with the KW v2, but now the nose will not squat anymore. The ride back home was slow traffic so I couldn't make more comment on the system yet. However, all my springs( i guess) squeak whenever they hit bump. I already ask Simon about it and hopefully will get that fixed soon.

Here is the video of the noise.

I am heading to race track the coming weekend and will report back more finding and settings

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Discussion Starter #155
That’s great news that you have them fitted and seem to be enjoying the benefits too. The noise you report is exactly the same as mine and is caused by the holes in OEM front top mounts being a larger diameter than the OEM fixing bolt meaning excess clearance so the damper moves in the mount, hence creating the noise. The fix for this (top hat washers and matching diameter bolts) is on the way from Tractive to Simon, so will no doubt be on the way to you soon to.

On a quiet road try turning the car left and right like when warming your tyres. Set everything to 1 and try it, then set 5 and do it again. The difference in turn-in precision is quite amazing, but especially feel the back end which becomes much, much more precise than OEM. I’m interested to know how it compares with your KW conventional dampers. Finally, set front and rear hardness to setting 1 and put Roll and Pitch to 5. You should experience reasonable ride comfort in a straight line, but with the above mentioned precision and feel when doing the tyre warming procedure.

Have you worked out how to change the screen display yet? The instructions aren’t quit right. Touch the screen in the top right, then touch it on the right hand side about half way vertically. This should Display Screen 2. Do the same for Display 3. Screen 4 (IIRC is calibration), and Screen 5 is an admin screen too. Repeat the action once again and you’re back to Screen 1.

You can set the screen brightness and change the default adjustment startup screen too. I can’t remember how without being in front of the screen, so will make notes when I get a chance. It’s possible to change the startup splash screen too. I knocked this up for mine. You’re welcome to a copy!

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I spent only like 40 mins driving it , and was afraid of the squeak would cause serious damage, but Simon got back to me and said it is normal, and I should keep driving it to make the bushing settle.

I too found the instructions are limited, and can't do anything besides setting up the hardness. For example, I am still trying to understand what is going to happen if I turn front and rear to full hardness, but have the pitch and roll at the softest setting, and what happen if I do it the otherway around. Is the setting bumping up the softest point or is it allowing to go harder when needed. Hopefully tractive can put some more information on their web site.

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Discussion Starter #157
Apologies if I’ve misinterpreted your question but this is my understanding of how the Tractive active setup works. The following force velocity curves (positive Y plots are bump settings and negative Y are rebound) are real plots but aren’t from a single damper: they’re from 2 dampers and were used to compare changes, but they’ll work for what I’m trying to illustrate. We’ll use each of the curves to illustrate 4 available settings softest, soft, firm and firmest (of course, you’ll have 5 plots because you have 5 settings but bear with me).

The shallowest green plot shows setting 1, and represents the firmest damping achievable on that softest setting. But when you’re driving along in steady state conditions - not braking, accelerating, turning, and with no significant bumps in the road - then the damping will be softer still. The controller unit has a 3D map for longitudinal, lateral and vertical acceleration, which compares accelerating force in each of these positive and negative directions and uses this map to open or close the DDA solenoid valve. Opening it makes damping softer and closing it make damping firmer. The damping will be soft when nothing significant is happening, but the moment the accelerometer sensors movement in one of three axes, then the damper could be automatically adjusted firmer up to the level shown in the green plot.

Similarly, the other plots illustrate the firmest damping available for each of the respective settings 2 (red plot), 3 (purple) and 4 (blue).

As well as the above, there are two more very clever bits: the first, is that if damping is set to ‘1’ but Roll set to ‘4’ (in this example ie 5 for yours), then damping maintains a maximum value of plot 1 for road imperfections and bumps, but the moment you turn in to a corner the damper setting changes in 6 mSecs up to the hardest setting, thus maintaining stability and providing the feel you’ll require. The level of firmness is decided by comparing acceleration to the 3D map so may be somewhere beneath the top curve if the cornering force isn’t at maximum. The second clever bit, is that for this setting, during this change from straight ahead to cornering, the outer dampers are automatically changed to a hard value of 4, but the inner dampers remain at 1, thus allowing maximum traction. It allows you to utilise track edge kerbing, if that’s your thing, because the wheel travelling over the kerb is relatively softly damped and can ride it well compared with the outer wheel on track which will have firm damping.

My current setup for fast road is 2 Front, 3 Roll, 3 Pitch, and 1 Rear. On track I’ve used 4 Front, 5 Roll, 5 Pitch and 3 Rear. I prefer softer damping settings (and therefore more compliant ride with maximum traction) with firmer roll and pitch when the accelerometer senses these.

Hope that helps!


103602
 

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Apologies if I’ve misinterpreted your question but this is my understanding of how the Tractive active setup works. The following force velocity curves (positive Y plots are bump settings and negative Y are rebound) are real plots but aren’t from a single damper: they’re from 2 dampers and were used to compare changes, but they’ll work for what I’m trying to illustrate. We’ll use each of the curves to illustrate 4 available settings softest, soft, firm and firmest (of course, you’ll have 5 plots because you have 5 settings but bear with me).

The shallowest green plot shows setting 1, and represents the firmest damping achievable on that softest setting. But when you’re driving along in steady state conditions - not braking, accelerating, turning, and with no significant bumps in the road - then the damping will be softer still. The controller unit has a 3D map for longitudinal, lateral and vertical acceleration, which compares accelerating force in each of these positive and negative directions and uses this map to open or close the DDA solenoid valve. Opening it makes damping softer and closing it make damping firmer. The damping will be soft when nothing significant is happening, but the moment the accelerometer sensors movement in one of three axes, then the damper could be automatically adjusted firmer up to the level shown in the green plot.

Similarly, the other plots illustrate the firmest damping available for each of the respective settings 2 (red plot), 3 (purple) and 4 (blue).

As well as the above, there are two more very clever bits: the first, is that if damping is set to ‘1’ but Roll set to ‘4’ (in this example ie 5 for yours), then damping maintains a maximum value of plot 1 for road imperfections and bumps, but the moment you turn in to a corner the damper setting changes in 6 mSecs up to the hardest setting, thus maintaining stability and providing the feel you’ll require. The level of firmness is decided by comparing acceleration to the 3D map so may be somewhere beneath the top curve if the cornering force isn’t at maximum. The second clever bit, is that for this setting, during this change from straight ahead to cornering, the outer dampers are automatically changed to a hard value of 4, but the inner dampers remain at 1, thus allowing maximum traction. It allows you to utilise track edge kerbing, if that’s your thing, because the wheel travelling over the kerb is relatively softly damped and can ride it well compared with the outer wheel on track which will have firm damping.

My current setup for fast road is 2 Front, 3 Roll, 3 Pitch, and 1 Rear. On track I’ve used 4 Front, 5 Roll, 5 Pitch and 3 Rear. I prefer softer damping settings (and therefore more compliant ride with maximum traction) with firmer roll and pitch when the accelerometer senses these.

Hope that helps!


View attachment 103602
Thanks for the clear information

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Came back from Track yesterday.

The last time I was on track was 7 months ago, and it took me 1 full day to get back to the rhythm and using the full hard brake.

I started testing the setting at 3 Front 4 Roll 4 Pitch and 4 Rear, but after a lap or 2 I thought there was some problem with the controller (the one at the back will G force sensor), as my car would crazy fish tail under hard braking. Like driving on ice, and there wasn't any force coming from the steering wheel, purely fish tail. So I had to return to pit lane and did some adjustment by using the knob, and finally found the car would only perform a controllable swing to the right at roll 2. I end up running 2 Front, 2 roll, 4 pitch and 3 rear.
During the day I can certainly feel the effect between the settings. From setting 3 and onward both my friend and I can tell there is something helping the car to turn, especially at 90 degree corner.
By the end of the day I had the car jacked up and checked if there was anything loose causing fish tail, but everything seemed tight and no binding issue. I then contacted Simon. He was very responsive and helpful, spent a great deal of time helping to find out the root cause. We both agreed that the system is running perfect and there must be something else that is acting up. Called my mechanic during the night, and he believed I have uneven brake pads as they were the old ones from the last track day 7 months ago💡

So day 2, I started running all setting at 3 as suggested by Simon, the fish tail was still there but only when I didn't brake with full force. End up running 2 at front and 3 for the rest. There were just so many car this time on the track, and my lap time was 2sec higher than my personal best due to traffic, and also it took me too long to get use to the new braking point (had to full brake all the time otherwise fish tail...) When I look at the Racechorno video, I found I have reach 1.3g in mid corner for multiple times, which I don't recall seeing so before. Anyway, great product, great service. Will head to track in 2 weeks with some new pads and keep you guys updated.
P.S someone took his FXX and it sounded so freaking amazing! ( It was a Zonda F at the back)

 

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Discussion Starter #160
It’s interesting to hear about the loose rear end as we have a very similar setup - my rear springs are 5Nmm softer than yours but other than that I think the setup is similar.

Other than the rear pad issue, I wonder did you fit new rear tyres before attending the track? My rear Michie Pilot Sport 4 tyres were replaced today and the new ones feel very different and imprecise compared with the old worn ones. They’ve been on for less than 20 miles so the release agent hasn’t cleared yet, but the difference is exaggerated compared with the usual change felt when new tyres are fitted. Both sets are manufactured in Spain so I’m wondering if the sidewall structure has been softened compared with the earlier ones.

I have track time booked at Thruxton circuit on Friday courtesy of Alpine, allowing me to compare the new setup against A110 and A110S models - it will also give me a chance to analyse how the rear feels under moderate and heavy braking so we can compare notes.

Had a message from Simon to say he’s received the new front top mount washers and bolts from Tractive designed to remove the free play causing the squeaking noise, so my car will be booked in soon for these and for softer rear springs to be fitted in my quest for an even more compliant ride.
 
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