Suspension Unloading At Launch..? (Vids)
09-17-2009, 01:08 PM
#21
Cutting the springs isnt helping at all. It completely ruins the way the spring reacts to situations like these. Ive seen some people run the V6 spring in the rear and the stockers in the front.
Either way, get actual lowering springs as they are made to preform at that designed height, stick the stock ones back on or live with the bad 60's.
Either way, get actual lowering springs as they are made to preform at that designed height, stick the stock ones back on or live with the bad 60's.
Mike
09-17-2009, 01:08 PM
#22
Yes and thanks man. I've read that thread about 10 times now. I think his statement about changing the IC and only making a couple hundredths difference, was probably referring to a full-on drag car that wasn't lowered and probably already cutting 1.3 60' times. LOL.... 
His definition of not getting traction doesn't match MY definition of not getting traction if you know what I mean. Madman is on a whole other league than me.
Wow, that low on tire pressure. That means I have lot's of room to work with then since I'm not running tubes either. I just didn't know how low I could get away with before it becomes a dangerous situation. Good info man, I appreciate it.
Mike
His definition of not getting traction doesn't match MY definition of not getting traction if you know what I mean. Madman is on a whole other league than me. Wow, that low on tire pressure. That means I have lot's of room to work with then since I'm not running tubes either. I just didn't know how low I could get away with before it becomes a dangerous situation. Good info man, I appreciate it.
Mike
Obviously lowering is really hurting you, but you already know that.
For a "no dollars" test, i would go back out with the car with the front swaybar off, and the tires at 10lbs. Much lower than that and the car really does walk a lot on the big end, so i would definitely take it in small steps.
09-17-2009, 01:09 PM
#23
****... just noticed you already had the swaybar off.
Just trying lowing the tire pressure and making the adjustments you had in mind on the instant center (never know... it may help more than im thinkin it will... my car wasn't lowered so i never messed with it that much)
Just trying lowing the tire pressure and making the adjustments you had in mind on the instant center (never know... it may help more than im thinkin it will... my car wasn't lowered so i never messed with it that much)
09-17-2009, 01:46 PM
#24
****... just noticed you already had the swaybar off.
Just trying lowing the tire pressure and making the adjustments you had in mind on the instant center (never know... it may help more than im thinkin it will... my car wasn't lowered so i never messed with it that much)
Just trying lowing the tire pressure and making the adjustments you had in mind on the instant center (never know... it may help more than im thinkin it will... my car wasn't lowered so i never messed with it that much)
Mike
09-17-2009, 08:55 PM
#25
TECH Fanatic
iTrader: (5)
Join Date: Mar 2007
Location: Evansville, IN
Posts: 1,199
Likes: 0
Received 0 Likes
on
0 Posts
Can you elaborate a little more on this? How does it "ruin" the way it reacts? It's a shorter spring with slightly more compressive tension than stock? I can understand the suspension geometry needing to be fixed (working on that), but I wouldn't think the springs are the root cause of the bad 60's. There are cars that are just as low, with stiffer springs than me and are 60 footing in the 1.5's.
Mike
Mike
Just a suggestion.
09-17-2009, 09:21 PM
#26
TECH Addict
iTrader: (75)
Join Date: Apr 2005
Location: Rock Hill, South Carolina
Posts: 2,578
Likes: 0
Received 0 Likes
on
0 Posts
i like my qa1 12 ways on all 4 corners with 275 drag springs up front and stock ls1 springs out back you can fine tune it pretty easy theyve worked well with small tires and big tires...
09-17-2009, 09:21 PM
#27
the front is your problem.
look at my vids from last week. blew the tires off then i went down two clicks on the front shocks.
I used to have revalved bilstiens on my car before. the only way i could make it hook was to run the rear very soft and like 11-12 psi
lowering the front of the arm will lift more weight and hit the tires softer. whats your rear LCA angle?
double adjustables on the rear is the best shock. even more than the front.
http://www.youtube.com/watch?v=drZHGYjuif0
http://www.youtube.com/watch?v=p5zM_TpNrk8
look at my vids from last week. blew the tires off then i went down two clicks on the front shocks.
I used to have revalved bilstiens on my car before. the only way i could make it hook was to run the rear very soft and like 11-12 psi
lowering the front of the arm will lift more weight and hit the tires softer. whats your rear LCA angle?
double adjustables on the rear is the best shock. even more than the front.
http://www.youtube.com/watch?v=drZHGYjuif0
http://www.youtube.com/watch?v=p5zM_TpNrk8
09-17-2009, 09:43 PM
#28
Competition Engineering 3way rear drag shocks
BMR LCA
BMR Adjustable torque arm
BMR panhard bar
BMR trans crossmember
BMR safety loop
BMR lowering springs
Energy Suspension mounts
UMI subframe connectors
GM 3.73 gear
PTC 4000 converter 2.4 STR
That is my suspension setup.. Race weight is 3550.. I cut consistent 1.52-1.54 short times on motor with 26" MT streets on a stock 8" camaro rim, dead hook... I want to lift the front wheels on the launch.. Is there anyway I could set the suspension up differently to make it lift the tires?
I am a suspension noob but have some buddies that know a little bit about it, no gurus though.. I know it will lift them on spray but I want to do it on motor first. I would be happy with both of them 8-12"..
Thanks for any advice..
BMR LCA
BMR Adjustable torque arm
BMR panhard bar
BMR trans crossmember
BMR safety loop
BMR lowering springs
Energy Suspension mounts
UMI subframe connectors
GM 3.73 gear
PTC 4000 converter 2.4 STR
That is my suspension setup.. Race weight is 3550.. I cut consistent 1.52-1.54 short times on motor with 26" MT streets on a stock 8" camaro rim, dead hook... I want to lift the front wheels on the launch.. Is there anyway I could set the suspension up differently to make it lift the tires?
I am a suspension noob but have some buddies that know a little bit about it, no gurus though.. I know it will lift them on spray but I want to do it on motor first. I would be happy with both of them 8-12"..
Thanks for any advice..
09-18-2009, 01:02 AM
#32
9 Second Club
iTrader: (20)
Join Date: Sep 2007
Location: Saline, MI
Posts: 1,813
Likes: 0
Received 0 Likes
on
0 Posts
http://bowtie0069.fotki.com/la-invas...9/img5374.html
here is a pic of my car with stock springs
m6 with 3.42 gears at 4500 rpm pulling 1.6s 60foot stock shocks and struts
its a 275/50/15MT DR with 17psi
stop being hard head and put some stock springs in. the higher a car sits the more LBS that gets transfered to the rear tires on take off
just do it !! LOL
here is a pic of my car with stock springs
m6 with 3.42 gears at 4500 rpm pulling 1.6s 60foot stock shocks and struts
its a 275/50/15MT DR with 17psi
stop being hard head and put some stock springs in. the higher a car sits the more LBS that gets transfered to the rear tires on take off
just do it !! LOL
09-18-2009, 01:14 AM
#34
9 Second Club
iTrader: (20)
Join Date: Sep 2007
Location: Saline, MI
Posts: 1,813
Likes: 0
Received 0 Likes
on
0 Posts
my car does 7.22 @ 105 in the 1/8th on 17in rim and 1.8 60 foots how funny is that LOL
09-18-2009, 01:32 AM
#35
7.2@105.....
I would just like to bring them up just to do it.. No other reason.. Some might thinks its lame (dont think that could be considered rice material
).. But would just like to do it on motor. 
09-18-2009, 04:59 AM
#38
12 Second Club
iTrader: (17)
Join Date: Dec 2004
Location: Cooper City, FL
Posts: 1,449
Likes: 0
Received 0 Likes
on
0 Posts
I think the springs are jus' as important as the shocks. From what I understand, you want to run a longer/softer spring. Being lowered 1.75" doesn't help transfer weight accordingly. If launching on a set of soft springs, the rear squats easier while at the same time the soft springs up front are lifting up the front end. If you still have your stock springs, jus' swap in the rears and see if you feel any improvement or bid on a set of V6 springs for the rear.
I watched and rewound that launch of the car you posted about 15 times and I didn't see the rearend squat at all. 
Someone correct me if I'm wrong, but I was under the impression that you DON'T want the rear to squat. Weight transfer, yes, but not at the expense of having the rearend squat down. When the suspension squats in the rear, it's actually the axle pushing up away from the ground and unloading the tires. I thought the ideal situation is to have the tires being driven into the ground, actually raising the rear of the car, as long as the tire can hold it.
Mike
Someone correct me if I'm wrong, but I was under the impression that you DON'T want the rear to squat. Weight transfer, yes, but not at the expense of having the rearend squat down. When the suspension squats in the rear, it's actually the axle pushing up away from the ground and unloading the tires. I thought the ideal situation is to have the tires being driven into the ground, actually raising the rear of the car, as long as the tire can hold it.
Mike
spohn anti roll bar. car setup was a stock bottom end ls1 w/ a 224/224, ported 243's and a 200 plate.
Chad
Last edited by Nimitz87; 09-18-2009 at 05:14 AM.
09-18-2009, 11:54 AM
#39
this is pretty wrong...you don't want the rear to squat at all.
Correct. your problem is no weight transfer at all, and your shock setup is killing you. the cut rear springs are fine...friend of mine has gone best of 1.32's on cut rear springs. qa1's front/rear. madman torque arm, LCA's, PHB.
spohn anti roll bar. car setup was a stock bottom end ls1 w/ a 224/224, ported 243's and a 200 plate.
Chad
Correct. your problem is no weight transfer at all, and your shock setup is killing you. the cut rear springs are fine...friend of mine has gone best of 1.32's on cut rear springs. qa1's front/rear. madman torque arm, LCA's, PHB.
spohn anti roll bar. car setup was a stock bottom end ls1 w/ a 224/224, ported 243's and a 200 plate.
Chad
My next major purchase for the car is going to be some drag shocks for the front, even though I REALLY want a 2-step lol....Mike
09-18-2009, 12:08 PM
#40
the front is your problem.
look at my vids from last week. blew the tires off then i went down two clicks on the front shocks.
I used to have revalved bilstiens on my car before. the only way i could make it hook was to run the rear very soft and like 11-12 psi
lowering the front of the arm will lift more weight and hit the tires softer. whats your rear LCA angle?
double adjustables on the rear is the best shock. even more than the front
look at my vids from last week. blew the tires off then i went down two clicks on the front shocks.
I used to have revalved bilstiens on my car before. the only way i could make it hook was to run the rear very soft and like 11-12 psi
lowering the front of the arm will lift more weight and hit the tires softer. whats your rear LCA angle?
double adjustables on the rear is the best shock. even more than the front
I'm excited about this, but bummed at the same time. Excited to see what a dramatic difference a front shock can make, but bummed out because I won't be able to afford those until next season. There goes my chances for getting a 10sec timeslip this year. 
I need to re-measure the LCA angle. It used to be 2 degrees but I haven't measured it since making the changes to the t/a. Pinion angle is now at -.5 using the driveshaft method.
Mike