Too stiff in the rear - Video
#1
Evolved Member
Thread Starter
iTrader: (62)
Join Date: Feb 2004
Location: Redmond - Lake Tapps ,WA
Posts: 3,336
Likes: 0
Received 6 Likes
on
6 Posts
Too stiff in the rear - Video
I decided to try an adjustment to the rear shocks on my car....
With my 450lb(8K) Front, and 550lb(10K) rear I have to run my 25mm Progress rear bar at full soft. Along with that I've had my bump setting at the minimum on the rear shocks. I decided to see what would happen if I increased the rear bump to the same as the front, which was about 3/4 full.
The results are at the end of this video...
http://www.vimeo.com/5948752
With my 450lb(8K) Front, and 550lb(10K) rear I have to run my 25mm Progress rear bar at full soft. Along with that I've had my bump setting at the minimum on the rear shocks. I decided to see what would happen if I increased the rear bump to the same as the front, which was about 3/4 full.
The results are at the end of this video...
http://www.vimeo.com/5948752
#3
Evolving Member
iTrader: (14)
Join Date: May 2007
Location: B-More
Posts: 194
Likes: 0
Received 0 Likes
on
0 Posts
I decided to try an adjustment to the rear shocks on my car....
With my 450lb(8K) Front, and 550lb(10K) rear I have to run my 25mm Progress rear bar at full soft. Along with that I've had my bump setting at the minimum on the rear shocks. I decided to see what would happen if I increased the rear bump to the same as the front, which was about 3/4 full.
The results are at the end of this video...
http://www.vimeo.com/5948752
With my 450lb(8K) Front, and 550lb(10K) rear I have to run my 25mm Progress rear bar at full soft. Along with that I've had my bump setting at the minimum on the rear shocks. I decided to see what would happen if I increased the rear bump to the same as the front, which was about 3/4 full.
The results are at the end of this video...
http://www.vimeo.com/5948752
I'm not convinced that the current trend of reversing spring rates is necessarily the best/fastest. If you have to have rebound settings way different from front to back to get a neutral car something's off. I had less of a difference front to rear than 'out of the box' set ups, but not swapped. then again what do I know
#4
Evolved Member
Thread Starter
iTrader: (62)
Join Date: Feb 2004
Location: Redmond - Lake Tapps ,WA
Posts: 3,336
Likes: 0
Received 6 Likes
on
6 Posts
It totally came from nowhere. I came in pretty fast, but the car was stable for the whole turn-in phase - then mid corner I felt the back end start to rotate and I tried to feed-in a mellow counter steer. But it didn't catch it.
The spring rate balance I run is based off a stock rear swaybar. But I was too lazy to swap out my 25mm Progress. That's the real issue. I've been fixing more major issues, and finally I'm getting back to setup adjustments. I'm going to try a smaller adjustable rear bar because having the ability to adjust the rear bar is nice. But I may just put the stock bar back on. We'll see.
The spring rate balance I run is based off a stock rear swaybar. But I was too lazy to swap out my 25mm Progress. That's the real issue. I've been fixing more major issues, and finally I'm getting back to setup adjustments. I'm going to try a smaller adjustable rear bar because having the ability to adjust the rear bar is nice. But I may just put the stock bar back on. We'll see.
Last edited by jid2; Aug 5, 2009 at 09:27 AM.
#5
Evolving Member
iTrader: (3)
Join Date: Mar 2004
Location: NorCal
Posts: 356
Likes: 0
Received 0 Likes
on
0 Posts
I decided to try an adjustment to the rear shocks on my car....
The results are at the end of this video...
http://www.vimeo.com/5948752
The results are at the end of this video...
http://www.vimeo.com/5948752
http://motorsports.briansarmy.ciscoe...thill-t4-save/
In that video I had 9/11k springs with Gerrard Ohlins and the 25mm Progress bar on medium stiff. I've since added 10mm spacers in the front to loosen it up a bit more.
Trending Topics
#8
Evolved Member
Thread Starter
iTrader: (62)
Join Date: Feb 2004
Location: Redmond - Lake Tapps ,WA
Posts: 3,336
Likes: 0
Received 6 Likes
on
6 Posts
That looked like a preventable spin but your hands were too slow. Check out my video from thill. Not perfect, but I saved it:
http://motorsports.briansarmy.ciscoe...thill-t4-save/
In that video I had 9/11k springs with Gerrard Ohlins and the 25mm Progress bar on medium stiff. I've since added 10mm spacers in the front to loosen it up a bit more.
http://motorsports.briansarmy.ciscoe...thill-t4-save/
In that video I had 9/11k springs with Gerrard Ohlins and the 25mm Progress bar on medium stiff. I've since added 10mm spacers in the front to loosen it up a bit more.
You are probably right about catching it. I've been over it in my head - with more throttle and a little more countersteer I think I could have slid the car through the corner. But I don't like the setup that loose
#9
Evolved Member
Thread Starter
iTrader: (62)
Join Date: Feb 2004
Location: Redmond - Lake Tapps ,WA
Posts: 3,336
Likes: 0
Received 6 Likes
on
6 Posts
It would be better with actual runoff on the back section, and new pavement. But it is has some cool elements for sure. Big elevation drop coming down the hill into the two hairpin corners, then racing back up the hill into the left-right-left section It's good stuff.
#10
Evolved Member
iTrader: (47)
Wow, in watching both vids, I gotta say my car has never handled like that. If I throw my car into a corner too fast it usually converts to an expected 4-wheel drift sideways to scrub the speed. I counter with steering input and start to build throttle back in to pull it out.
Maybe setup differences, maybe driver style or preference? And I've ran the same suspension setup all year, both with street tires, r-comps and hoosiers. I'm not a fan of a loose rear myself (any accidental puns totally intended)
Maybe setup differences, maybe driver style or preference? And I've ran the same suspension setup all year, both with street tires, r-comps and hoosiers. I'm not a fan of a loose rear myself (any accidental puns totally intended)
#11
Former Sponsor
iTrader: (35)
looked like it came out of nowhere.
I'm not convinced that the current trend of reversing spring rates is necessarily the best/fastest. If you have to have rebound settings way different from front to back to get a neutral car something's off. I had less of a difference front to rear than 'out of the box' set ups, but not swapped. then again what do I know
I'm not convinced that the current trend of reversing spring rates is necessarily the best/fastest. If you have to have rebound settings way different from front to back to get a neutral car something's off. I had less of a difference front to rear than 'out of the box' set ups, but not swapped. then again what do I know
Also, the stock rear spring on the KW's is only 6k with valving to match....
I'll watch the video when i get home. Sounds fun.
- drew
#12
Evolved Member
iTrader: (5)
Join Date: May 2004
Location: SL,UT
Posts: 3,601
Likes: 0
Received 0 Likes
on
0 Posts
Wow, Jared, I knew you were a crappy driver... but jeez. Looked like fun! The Utah crowd misses you man. Wes got some of the lowering brackets and he loves em, I sat in his car and now I demand you make some for the GR STi!
#13
Evolved Member
iTrader: (5)
Wow, in watching both vids, I gotta say my car has never handled like that. If I throw my car into a corner too fast it usually converts to an expected 4-wheel drift sideways to scrub the speed. I counter with steering input and start to build throttle back in to pull it out.
Maybe setup differences, maybe driver style or preference? And I've ran the same suspension setup all year, both with street tires, r-comps and hoosiers. I'm not a fan of a loose rear myself (any accidental puns totally intended)
Maybe setup differences, maybe driver style or preference? And I've ran the same suspension setup all year, both with street tires, r-comps and hoosiers. I'm not a fan of a loose rear myself (any accidental puns totally intended)
Coming from both FWD background and RWD background, I prefer the typical RWD "touch of controllable oversteer" to the FWD "understeer until it snap oversteers" way of seeing the world.
I want (and for the most part have setup my car to) a touch of oversteer that's controllable (meaning, like you describe, a bit of countersteer and throttle holds it or pulls you out).
Getting there (and staying there) is a huge battle though, involving stiffening up the rear a lot, playing with front and rear camber and sway bars and tire settings (air pressure differentials, etc.).
Of course, any new track and tire setup really messes with this "balance" as I found out a couple weeks ago where I looped it until I realized that my air pressures were way too high for the surface. Once I let air out the car felt like my car again.
I need a notebook/blackberry app/iphone app to keep track of my car settings, environment settings, track conditions, etc. so that I can log this stuff better... as a mistake can be very dangerous :-/
#15
Evolved Member
iTrader: (15)
KW's do not use the same exact valving front and rear, so 1/2 turn front is not the same as 1/2 turn rear. They shouldn't be compared to each other that way.
Also, the stock rear spring on the KW's is only 6k with valving to match....
I'll watch the video when i get home. Sounds fun.
- drew
Also, the stock rear spring on the KW's is only 6k with valving to match....
I'll watch the video when i get home. Sounds fun.
- drew