Building Suspension for Road Racing?
06-29-09, 11:09 PM
#1
Driver School Candidate
Thread Starter
Join Date: Jun 2009
Location: MO
Posts: 39
Likes: 0
Received 0 Likes
on
0 Posts
Building Suspension for Road Racing?
Ok, so I realize that this is not that common of a road raced car, or drifted, or autocrossed, or whatever. But i come from an S14 backround of stiff suspension and roll cages galore, so thats all the car was about.
Say if i had a Lexus SC300, and wanted it to handle like a mother ****er, what steps would i take? Assuming i already have coilovers (Kei Office).
Do Supra STB's fit? Which ones are easily available? etc...
Say if i had a Lexus SC300, and wanted it to handle like a mother ****er, what steps would i take? Assuming i already have coilovers (Kei Office).
Do Supra STB's fit? Which ones are easily available? etc...
06-30-09, 05:59 AM
#2
do some searching and everything will become more clear. everything that is available for the S14 is available for the SC....
Autopower makes a cage, Stance coilovers, prothane bushings, solid subframe mounts, solid diff mounts ETC and your good. just all costs money.
Autopower makes a cage, Stance coilovers, prothane bushings, solid subframe mounts, solid diff mounts ETC and your good. just all costs money.
07-01-09, 12:09 AM
#6
Quantum-Auto has some in the works too! 
http://www.quantum-auto.com/
They should be loads cheaper than the Ikeya ones too!
http://www.quantum-auto.com/
They should be loads cheaper than the Ikeya ones too!
07-03-09, 09:52 AM
#7
http://uza70.com/store/catalog/produ...m43lon9beitct3
this has got to be the worse mod. No one should ever buy this and no one with any knowlege of suspension would ever make that.
this has got to be the worse mod. No one should ever buy this and no one with any knowlege of suspension would ever make that.
Trending Topics
07-03-09, 01:01 PM
#8
Lead Lap
iTrader: (1)
Join Date: Jan 2009
Location: CO
Posts: 660
Likes: 0
Received 0 Likes
on
0 Posts
I'm planning on open-tracking my car as well. I've got MkIV Bilsteins on their way (FINALLY) to do a gixxer_drew setup with 600lb fronts and 400lb rears. That'll make a huge difference right there, but I also need to go through the rear suspension and replace bushings. I may just go poly for that. Once that stuff is done it'll be ready for at least an HPDE1 session, but it's gonna suck as an automatic. Five-speed swap is going to be the next major project to save up for, and I think it'll make the biggest difference in driveability.
07-05-09, 03:34 AM
#9
Lexus Test Driver
iTrader: (4)
Join Date: Jun 2004
Location: Portland
Posts: 933
Likes: 0
Received 0 Likes
on
0 Posts
I have had my sc on a road course a couple of times and have done a few autoxs with it. Here are some observations I have made:
-Sway bars are necessary. You will find the SC understeers pretty bad at the limit. At the least I would recommend going with factory TT supra pieces. These are what I am currently running and helped balance the car very well, it also corners much flatter. It will still understeer slightly at the limit, but it is nothing compared to running on stock sways.
-You said you already have coilovers, which is good.
-Upgraded brakes. The stock brakes on SCs are pretty worthless for high performance driving, they are undersized and in my opinion lexus should have put the LS400 front on SCs from the factory. I am running LS400 brakes, they are an excellent upgrade, and very budget friendly. They are harder to find good brake pads for than TT brakes however.
-LSD. After the first time I did an autox event in my car I found that our open diff does not cut it on tight autox courses. I still do not have an LSD, but it is definitely at the top of my shopping list currently. This is especially necessary if you are turbo, but even in an NA car I would recommend running an LSD.
-I recently installed a full poly bushing kit and I am very impressed with how much it tightened up the suspension.
-Wheels/tires. This should be pretty obvious but the narrow stock wheels and tires don't cut it, and if you upgrade your brakes they will not clear the calipers anyways. I am running supra TT rims, they are cheap, wide and clear upgraded brakes.
-Weight reduction. Removing unnecessary weight in our cars is easy, its not difficult to remove 100-150 lbs and still have a complete interior. There are a few threads that detail several things you can do.
-Seats. Factory SC seats are heavy and not well bolstered. I am running TT seats, which will save you a few lbs, sit lower, and are compatible with harnesses.
Next things I am going to focus on are:
1. Getting a LSD, probably going with the supra TT auto rear end.
2. Stiffening up the chassis a little bit. Getting a front STB and a roll bar with harness bar.
3. Purchasing an extra set of TT rims and lacing them up with hoosiers or kumho v710s.
The SupraForums AutoX and Roadracing forum is great resource as is SoarerCentral! Good luck!
Josh
-Sway bars are necessary. You will find the SC understeers pretty bad at the limit. At the least I would recommend going with factory TT supra pieces. These are what I am currently running and helped balance the car very well, it also corners much flatter. It will still understeer slightly at the limit, but it is nothing compared to running on stock sways.
-You said you already have coilovers, which is good.
-Upgraded brakes. The stock brakes on SCs are pretty worthless for high performance driving, they are undersized and in my opinion lexus should have put the LS400 front on SCs from the factory. I am running LS400 brakes, they are an excellent upgrade, and very budget friendly. They are harder to find good brake pads for than TT brakes however.
-LSD. After the first time I did an autox event in my car I found that our open diff does not cut it on tight autox courses. I still do not have an LSD, but it is definitely at the top of my shopping list currently. This is especially necessary if you are turbo, but even in an NA car I would recommend running an LSD.
-I recently installed a full poly bushing kit and I am very impressed with how much it tightened up the suspension.
-Wheels/tires. This should be pretty obvious but the narrow stock wheels and tires don't cut it, and if you upgrade your brakes they will not clear the calipers anyways. I am running supra TT rims, they are cheap, wide and clear upgraded brakes.
-Weight reduction. Removing unnecessary weight in our cars is easy, its not difficult to remove 100-150 lbs and still have a complete interior. There are a few threads that detail several things you can do.
-Seats. Factory SC seats are heavy and not well bolstered. I am running TT seats, which will save you a few lbs, sit lower, and are compatible with harnesses.
Next things I am going to focus on are:
1. Getting a LSD, probably going with the supra TT auto rear end.
2. Stiffening up the chassis a little bit. Getting a front STB and a roll bar with harness bar.
3. Purchasing an extra set of TT rims and lacing them up with hoosiers or kumho v710s.
The SupraForums AutoX and Roadracing forum is great resource as is SoarerCentral! Good luck!
Josh
Last edited by CLNSC3; 07-05-09 at 12:13 PM.
07-05-09, 11:23 AM
#10
I'm planning on open-tracking my car as well. I've got MkIV Bilsteins on their way (FINALLY) to do a gixxer_drew setup with 600lb fronts and 400lb rears. That'll make a huge difference right there, but I also need to go through the rear suspension and replace bushings. I may just go poly for that. Once that stuff is done it'll be ready for at least an HPDE1 session, but it's gonna suck as an automatic. Five-speed swap is going to be the next major project to save up for, and I think it'll make the biggest difference in driveability.
07-05-09, 05:19 PM
#12
fyi, when i swapped out both front seats with bride cfrp seats and the hood and trunk to seibon cf parts, i lost 170lbs.
right now, i'm riding on all ikeya arms and top secret coils (16fr/12rr) and the handling is superb. i'm anxious to hit the track more now.
right now, i'm riding on all ikeya arms and top secret coils (16fr/12rr) and the handling is superb. i'm anxious to hit the track more now.
07-05-09, 06:18 PM
#13
http://uza70.com/store/catalog/produ...m43lon9beitct3
this has got to be the worse mod. No one should ever buy this and no one with any knowlege of suspension would ever make that.
this has got to be the worse mod. No one should ever buy this and no one with any knowlege of suspension would ever make that.
I pm'd you. I would love some insight, just because the idea is based off circle track cars.
Last edited by RedPhoenix; 07-05-09 at 06:32 PM.
07-05-09, 11:51 PM
#14
Everyone on forums always thinks that moving the tie rod down actually makes your bumpsteer better. Can you prove that other then its based off of whats on some circle track car? I dont really want to go into the whole thing about suspension design but what works for some people does not work for others.
07-11-09, 11:33 AM
#15
Driver
Join Date: Jul 2007
Location: Florida
Posts: 199
Likes: 0
Received 0 Likes
on
0 Posts
http://uza70.com/store/catalog/produ...m43lon9beitct3
this has got to be the worse mod. No one should ever buy this and no one with any knowlege of suspension would ever make that.
this has got to be the worse mod. No one should ever buy this and no one with any knowlege of suspension would ever make that.