Yeah, baby, I've got air!
#33
Drifting
Join Date: May 2003
Location: Charlotte, NC
Posts: 2,585
Likes: 0
Received 0 Likes
on
0 Posts
On our car: Helper springs, smallish front bar connected to the control arms rather than the struts to further limit it's effective rate, roll center adjustments to the subframe and control arms to limit roll through geometry, and increased track width of 2+ inches over the stock control arms through the use of a tubular front arm.
Thanks to the wider track and improved roll center geometry, we're able to run a relatively soft front spring, which further helps to add additional rebound travel.
As has been mentioned in this thread as well, things you do to the back also affect the front. We run no rear anti-roll bar in order to maximize rear acceleration travel, but rebound damping and other things must be considered to make sure the rear doesn't totally squat coming out of the turn and carry the nose.
For the guys running 1300+ pound spring rates, what kind of dampers are you running? It takes good dampers to control such a heavy spring over such a very small range of movement.
#34
Rennlist
Basic Site Sponsor
Basic Site Sponsor
Moton 3-way motorsport shocks.
__________________
Larry Herman
2016 Ford Transit Connect Titanium LWB
2018 Tesla Model 3 - Electricity can be fun!
Retired Club Racer & National PCA Instructor
Past Flames:
1994 RS America Club Racer
2004 GT3 Track Car
1984 911 Carrera Club Racer
1974 914/4 2.0 Track Car
CLICK HERE to see some of my ancient racing videos.
Larry Herman
2016 Ford Transit Connect Titanium LWB
2018 Tesla Model 3 - Electricity can be fun!
Retired Club Racer & National PCA Instructor
Past Flames:
1994 RS America Club Racer
2004 GT3 Track Car
1984 911 Carrera Club Racer
1974 914/4 2.0 Track Car
CLICK HERE to see some of my ancient racing videos.
#35
Drifting
Join Date: May 2003
Location: Charlotte, NC
Posts: 2,585
Likes: 0
Received 0 Likes
on
0 Posts
#37
Todd-
Thanks for allowing those of us who are neophytes in suspension engineering to use your example.
In addition to Bryan's comments (and he obviously knows alot more than me) in looking at pictures of cars that are "set up" two thoughts occur to me when I see a pic like your's.
1. The road just drops off as is the case on the inside of many corners...
2. that the car doesn't have enough rear spring to keep the outside rear corner from squating too much.
As my friend the engineer said all cars flex and as is the case in most cages you don't have your cage welded to the strut housing so there will always be some flex.
I've tracked a Boxster S as well as my 944 SuperCup. When the cars were near stock configuration with R comps on it was relatively easy to get a tire off the ground comming out of Oak Tree @ VIR. Now with a much stiffer rear end I can't get a picture of me lifting a tire there.
Food for thought.
PS - Todd in looking at your signature I would have thought that you would run stiffer springs in the rear as it is a rear weight biased car. I'd be intrested in why you did what you did.
Thanks for allowing those of us who are neophytes in suspension engineering to use your example.
In addition to Bryan's comments (and he obviously knows alot more than me) in looking at pictures of cars that are "set up" two thoughts occur to me when I see a pic like your's.
1. The road just drops off as is the case on the inside of many corners...
2. that the car doesn't have enough rear spring to keep the outside rear corner from squating too much.
As my friend the engineer said all cars flex and as is the case in most cages you don't have your cage welded to the strut housing so there will always be some flex.
I've tracked a Boxster S as well as my 944 SuperCup. When the cars were near stock configuration with R comps on it was relatively easy to get a tire off the ground comming out of Oak Tree @ VIR. Now with a much stiffer rear end I can't get a picture of me lifting a tire there.
Food for thought.
PS - Todd in looking at your signature I would have thought that you would run stiffer springs in the rear as it is a rear weight biased car. I'd be intrested in why you did what you did.
#38
Pro
Thread Starter
Join Date: Dec 2002
Location: Dana Point, CA
Posts: 502
Likes: 0
Received 0 Likes
on
0 Posts
I will probably switch to different springs sometime this year, but I've already poured too many thousands of dollars into fixing the problems with this car this year to spend anything more.
#39
Addict
Rennlist Member
Rennlist Member
Well, my 911 Targa lifts the inside front and I wouldn't put that car in the "minimal chassis flex" category In older 911's at least, I believe it's due to the front roll center being too low.
#41
CHP Boxster Look-a-like
Wow, great setup.
Todd...
Your car looks alot like the one featured in Excellence June of 2006.
Is this were you got the idea?
Of course the Shadow is Much more Aggressive, I can't help but think how awesome a whole fleet of Boxster Patrol Cars would look.
Maybe that should be a required SpecBoxster Color scheme. I am surprised we haven't run at the same events yet.
The Shadow has been masquerading as a Patrol car Since 2003!
Check out the website For The Official CHP Boxster.
http://www.chpboxster.com/
Todd...
Your car looks alot like the one featured in Excellence June of 2006.
Is this were you got the idea?
Of course the Shadow is Much more Aggressive, I can't help but think how awesome a whole fleet of Boxster Patrol Cars would look.
Maybe that should be a required SpecBoxster Color scheme. I am surprised we haven't run at the same events yet.
The Shadow has been masquerading as a Patrol car Since 2003!
Check out the website For The Official CHP Boxster.
http://www.chpboxster.com/