How does car handle on track with new Coilover setup
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From: Boston/Hartford
How does car handle on track with new Coilover setup
Hi,
i realized that I had been hijacking a lot of threads with suspension questions so I decided to start a new one. I would really like to hear about the tendencies of the car and how it handles with new coilvers. I am especially interested in hearing from people who have tried the pss9's and carlsson as that is what I have but I also want to hear how the other coilover kits help as well.
I am going to be going to the track in about a week or so for the first time with the following mods and I didn't want to be surprised too much. My car has been stock so far.
The mods I am going to put in are the Carlsson RS with factory camber correction bolts and the most negative camber i can get from them. 13.5" fr and 13.0 rr will be the ride heights. I will be using the stock wheels with the kumho's one day and the HRE's with Toyos the next. I will have new stock rotors with the porterfield r4-e.
Here is what I have observed so far and want to know how these behaviours change with the addition of the mods.
1) When I am braking hard and try to turn in (usually after a long straight and into a corner) the back wiggles and it almost seems like it might break loose. SMG indicated that it may be because the bushings are soft on the rear. I also seem to think it may be because of the rear shocks and the rear spring setup.
2) Coming out of the turns I have lots of trouble accelerating WOT as it really unsettles the car. I usually have to feather the throttle and I am not able to get on fully until almost towards the end. This has to do more because of the speedshift I think as it shifts for me if I get on the gas semi-hard at the apex.
3) On long sweeper turns the car is just hurting for traction and I am usually sliding my front tires all the way through.
4) Especially on double apex turns I have trouble coming back in for the second apex as the car can't seem to grip in time to right itself for the second apex.
Finally I have never spun "this" car (I came close once but recovered). How does this change with the new suspension?
How does ESP work? Does it come on more? Less? Same?
Thanks and if anybody wishes to share their experience it would be much appreciated.
I will be running with mostly BMW's (they will be mostly instructors so I should have my butt handed to me) but I plan to get a camera and shoot some video as well.
Prasith
i realized that I had been hijacking a lot of threads with suspension questions so I decided to start a new one. I would really like to hear about the tendencies of the car and how it handles with new coilvers. I am especially interested in hearing from people who have tried the pss9's and carlsson as that is what I have but I also want to hear how the other coilover kits help as well.
I am going to be going to the track in about a week or so for the first time with the following mods and I didn't want to be surprised too much. My car has been stock so far.
The mods I am going to put in are the Carlsson RS with factory camber correction bolts and the most negative camber i can get from them. 13.5" fr and 13.0 rr will be the ride heights. I will be using the stock wheels with the kumho's one day and the HRE's with Toyos the next. I will have new stock rotors with the porterfield r4-e.
Here is what I have observed so far and want to know how these behaviours change with the addition of the mods.
1) When I am braking hard and try to turn in (usually after a long straight and into a corner) the back wiggles and it almost seems like it might break loose. SMG indicated that it may be because the bushings are soft on the rear. I also seem to think it may be because of the rear shocks and the rear spring setup.
2) Coming out of the turns I have lots of trouble accelerating WOT as it really unsettles the car. I usually have to feather the throttle and I am not able to get on fully until almost towards the end. This has to do more because of the speedshift I think as it shifts for me if I get on the gas semi-hard at the apex.
3) On long sweeper turns the car is just hurting for traction and I am usually sliding my front tires all the way through.
4) Especially on double apex turns I have trouble coming back in for the second apex as the car can't seem to grip in time to right itself for the second apex.
Finally I have never spun "this" car (I came close once but recovered). How does this change with the new suspension?
How does ESP work? Does it come on more? Less? Same?
Thanks and if anybody wishes to share their experience it would be much appreciated.
I will be running with mostly BMW's (they will be mostly instructors so I should have my butt handed to me) but I plan to get a camera and shoot some video as well.
Prasith
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Joined: Sep 2002
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Mercedes Benz
Re: How does car handle on track with new Coilover setup
1) When I am braking hard and try to turn in (usually after a long straight and into a corner) the back wiggles and it almost seems like it might break loose. SMG indicated that it may be because the bushings are soft on the rear. I also seem to think it may be because of the rear shocks and the rear spring setup.
------> This has to do with two items. The first is the fact that the rear bushings are not very firm. RENNtech designed the rear subframe kit to eliminate this issue. The second reason is that when you unload the rear axle there is a change in toe during the weight transfer. This makes the car track differently. THe fact that the bushings are too soft makes this problem even wrose being it doubles the toe change seen in the suspensions natural geometry.
2) Coming out of the turns I have lots of trouble accelerating WOT as it really unsettles the car. I usually have to feather the throttle and I am not able to get on fully until almost towards the end. This has to do more because of the speedshift I think as it shifts for me if I get on the gas semi-hard at the apex.
-----> This is inproved with the RS kit and a proper corner ballancing. The issue here is that you need to be in gear at turn in so that you can slowly add power after the apex. You would not want to go to WOT at the apex but keeping it in gear and in the power band lets you add power as needed. When the car shifts leaving the corner, the ESP system always causes the car to hick-up becasue the torque converter makes the drive wheels jerk a bit.
3) On long sweeper turns the car is just hurting for traction and I am usually sliding my front tires all the way through.
-----> At the Streets of Willow (where steve and I run his car most often) there is a long sweeping corner and the car feels 100% planted (the turn running into the bowl). I can play with the throttle anywhere in the corner and place the car exactly at the turn in cone for the next corner every time. To much push and you just back out 10% on the gas and the gets right back on line. The was no hunting for grip in sweepers but a bit in tight corners.
4) Especially on double apex turns I have trouble coming back in for the second apex as the car can't seem to grip in time to right itself for the second apex.
-----> Yes the kit and the camber will add enough front grip to make double apex corners more of your friend. In stock form the car never wants to tuck back in without a serious drop in throttle position. The RS kit is of help here. THe streets does have a double apex corner but both steve and I ignore the first and set the car for the second being that this allows us to enter the next corner with a much needed late turn in.
Finally I have never spun "this" car (I came close once but recovered). How does this change with the new suspension?
----> I am new to track events and I was able to get the car to lap just 1.2 seconds slower than steve by the end of the day. Give me a second day at the track and I know I can get down to with in 1 second of steves new set of fast laps (i missed the last one as I was at Indy for the F1 race)! With my best lap being a 1:39xx I never once felt fearful when the car did step out a bit. Infact I enjoyed the back getting a bit wide in some turns for it helped the car rotate though the corner. The car was extremely easy to drive and I would call it almost to tame
How does ESP work? Does it come on more? Less? Same?
-----> ESP worked flawlessly and the car is almost no faster with the system on vs. off. When off however the tail will come out fairly quickly but quick hands makes it get back in place before anything gets out of hand.
SMGC32 -- What is your take? I am sure you can write us a SMG novel on this topic
------> This has to do with two items. The first is the fact that the rear bushings are not very firm. RENNtech designed the rear subframe kit to eliminate this issue. The second reason is that when you unload the rear axle there is a change in toe during the weight transfer. This makes the car track differently. THe fact that the bushings are too soft makes this problem even wrose being it doubles the toe change seen in the suspensions natural geometry.
2) Coming out of the turns I have lots of trouble accelerating WOT as it really unsettles the car. I usually have to feather the throttle and I am not able to get on fully until almost towards the end. This has to do more because of the speedshift I think as it shifts for me if I get on the gas semi-hard at the apex.
-----> This is inproved with the RS kit and a proper corner ballancing. The issue here is that you need to be in gear at turn in so that you can slowly add power after the apex. You would not want to go to WOT at the apex but keeping it in gear and in the power band lets you add power as needed. When the car shifts leaving the corner, the ESP system always causes the car to hick-up becasue the torque converter makes the drive wheels jerk a bit.
3) On long sweeper turns the car is just hurting for traction and I am usually sliding my front tires all the way through.
-----> At the Streets of Willow (where steve and I run his car most often) there is a long sweeping corner and the car feels 100% planted (the turn running into the bowl). I can play with the throttle anywhere in the corner and place the car exactly at the turn in cone for the next corner every time. To much push and you just back out 10% on the gas and the gets right back on line. The was no hunting for grip in sweepers but a bit in tight corners.
4) Especially on double apex turns I have trouble coming back in for the second apex as the car can't seem to grip in time to right itself for the second apex.
-----> Yes the kit and the camber will add enough front grip to make double apex corners more of your friend. In stock form the car never wants to tuck back in without a serious drop in throttle position. The RS kit is of help here. THe streets does have a double apex corner but both steve and I ignore the first and set the car for the second being that this allows us to enter the next corner with a much needed late turn in.
Finally I have never spun "this" car (I came close once but recovered). How does this change with the new suspension?
----> I am new to track events and I was able to get the car to lap just 1.2 seconds slower than steve by the end of the day. Give me a second day at the track and I know I can get down to with in 1 second of steves new set of fast laps (i missed the last one as I was at Indy for the F1 race)! With my best lap being a 1:39xx I never once felt fearful when the car did step out a bit. Infact I enjoyed the back getting a bit wide in some turns for it helped the car rotate though the corner. The car was extremely easy to drive and I would call it almost to tame
How does ESP work? Does it come on more? Less? Same?
-----> ESP worked flawlessly and the car is almost no faster with the system on vs. off. When off however the tail will come out fairly quickly but quick hands makes it get back in place before anything gets out of hand.
SMGC32 -- What is your take? I am sure you can write us a SMG novel on this topic
