C4 Tech/Performance L98 Corvette and LT1 Corvette Technical Info, Internal Engine, External Engine

Suspension question

Thread Tools
 
Search this Thread
 
Old Apr 6, 2012 | 05:59 PM
  #1  
scottermis's Avatar
scottermis
Thread Starter
Advanced
 
Joined: Dec 2011
Posts: 57
Likes: 0
From: Edmond OK
Default Suspension question

I put new Bilsteins on my 94 after i bought it with shocks that were worn out. Assuming the new Bilsteins would take out the "boat effect" at high speeds 70+ i was a bit dissappointed. What do i need to do to make the suspension a bit stiffer do i need to put a suspension kit on it or can i do something cheaper?
Reply
Old Apr 6, 2012 | 06:39 PM
  #2  
2fas2c's Avatar
2fas2c
Instructor
 
Joined: Nov 2011
Posts: 211
Likes: 1
Default

what are the cond. of your ball joints, tie rods rear center link and bushings? replacing the all the susp. bushings with urethane ones is a good cheap upgrade and reduces body roll quite a bit. If your ball joints + tie rods are in disrepair I would start there though, no sense in upgrading if the basics are no good. While your in there replace the end links.
Reply
Old Apr 6, 2012 | 07:13 PM
  #3  
jaa1992's Avatar
jaa1992
Le Mans Master
25 Year Member
Conversation Starter
All Eyes On Me
 
Joined: Mar 2001
Posts: 7,999
Likes: 14
From: Life is just one big track event. Everything before and after is prep and warm-up and cool-down laps
Cruise-In III Veteran
Cruise-In IV Veteran
St. Jude Donor '12
Default

Explain "boat effect"?
If that means the front end feels light like its comming up - check your front air dam and make sure ALL the pieces are there and in good shape.
Mine would start to lift at 80+ on the straight on a road course cause one piece of the air dam was damaged.
Reply
Old Apr 6, 2012 | 07:31 PM
  #4  
scottermis's Avatar
scottermis
Thread Starter
Advanced
 
Joined: Dec 2011
Posts: 57
Likes: 0
From: Edmond OK
Default

Originally Posted by jaa1992
Explain "boat effect"?
If that means the front end feels light like its comming up - check your front air dam and make sure ALL the pieces are there and in good shape.
Mine would start to lift at 80+ on the straight on a road course cause one piece of the air dam was damaged.


Ip ut a set of SU-814 and SU-815 Bilsteins on the car a month ago and it has 33k miles on it. Being a 94 model it has really low mileage buti replaced the old Bilsteins as they were the original shocks that came on it. I think maybe i expected a little tighter suspension on the car as i have never owned a vette before but the air dam and most everything on the car are in pretty perfect shape. The front of the car just feels like it floats some on an aggressive start or driving on the interstate as around 70-130. Maybe it is just me and its an older car and is supposed to be that way?
Reply
Old Apr 6, 2012 | 08:47 PM
  #5  
rodj's Avatar
rodj
Le Mans Master
25 Year Member
 
Joined: Aug 2000
Posts: 8,838
Likes: 31
From: Australia
Default

Originally Posted by scottermis
I think maybe i expected a little tighter suspension . The front of the car just feels like it floats some on an aggressive start or driving on the interstate as around 70-130. Maybe it is just me and its an older car and is supposed to be that way?
The later C4's like yours are way softer than the earlier cars because the golf club on Sunday set first owners
wanted a luxury performance car ; not a performance car , so GM soften up the suspension to accommodate them
Fitting the springs / swaybars from a earlier (>'88 car) will regain some control ( stiffer ) but with a obvious loss
of ride comfort if you are looking for Caddy quality at the same time
Reply
Old Apr 6, 2012 | 08:48 PM
  #6  
93Rubie's Avatar
93Rubie
Safety Car
15 Year Member
Liked
Loved
Community Favorite
 
Joined: Sep 2010
Posts: 3,752
Likes: 190
From: Indiana PA
Default

Originally Posted by scottermis
Ip ut a set of SU-814 and SU-815 Bilsteins on the car a month ago and it has 33k miles on it. Being a 94 model it has really low mileage buti replaced the old Bilsteins as they were the original shocks that came on it. I think maybe i expected a little tighter suspension on the car as i have never owned a vette before but the air dam and most everything on the car are in pretty perfect shape. The front of the car just feels like it floats some on an aggressive start or driving on the interstate as around 70-130. Maybe it is just me and its an older car and is supposed to be that way?
What suspension do you have base, FX3?

The 94's have some soft springs and with base suspension soft shocks. My buddies 94 feels way softer than my 93 FX3 does even in touring mode.
Reply
Old Apr 13, 2012 | 10:17 AM
  #7  
scottermis's Avatar
scottermis
Thread Starter
Advanced
 
Joined: Dec 2011
Posts: 57
Likes: 0
From: Edmond OK
Default

Originally Posted by rodj
The later C4's like yours are way softer than the earlier cars because the golf club on Sunday set first owners
wanted a luxury performance car ; not a performance car , so GM soften up the suspension to accommodate them
Fitting the springs / swaybars from a earlier (>'88 car) will regain some control ( stiffer ) but with a obvious loss
of ride comfort if you are looking for Caddy quality at the same time

Would coilovers be a good option and if so can anyone recommend a good brand?
Reply
Old Apr 13, 2012 | 11:35 PM
  #8  
Analog Kid's Avatar
Analog Kid
Instructor
20 Year Member
All Eyes On Me
 
Joined: Jan 2004
Posts: 169
Likes: 4
From: I celebrate their entire catalog
Default

Check the diameter of your front sway bar. Sometime in the last few years of the C4 production run, they started putting 24mm front bars on the base/FE1 models and you get the poor high speed feel you are describing.
You can go up to 26mm, 28 or 32 using factory bars from different models (junk yard). There are companies that sell them as well.
I picked up a used 26mm bar and bought some poly sway bar bushings and it made a huge difference.
Reply
Corvette Stories

The Best of Corvette for Corvette Enthusiasts

story-0

150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

 Joe Kucinski
story-1

8 Coolest Corvette Pace Cars (and Replicas) of All Time

 Verdad Gallardo
story-2

Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)

 Joe Kucinski
story-3

Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!

 Verdad Gallardo
story-4

Top 10 Corvettes Coming to Mecum Indy 2026!

 Brett Foote
story-5

Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!

 Michael S. Palmer
story-6

10 Revolutionary 'Corvette Firsts' Most People Don't Know

 Joe Kucinski
story-7

5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

 Michael S. Palmer
story-8

2027 Corvette vs The World: Every C8 vs Its Closest Competitor

 Joe Kucinski
story-9

10 Most Common Corvette Problems of the Last 20 Years!

 Joe Kucinski
Old Apr 14, 2012 | 08:54 AM
  #9  
Churchkey's Avatar
Churchkey
Melting Slicks
10 Year Member
 
Joined: Sep 2008
Posts: 2,376
Likes: 111
From: Cherokee National Forest TN
Default

I would keep the soft springs.

The front running short track pavement oval cars use soft springs, good shocks & large sway bars.

Suggest checking the front wheel alignment to insure there is enough caster. Light caster settings will give a loose front end feel at speed. On vehicles that have tires with a large foot print like our Vettes the loose feed back feel is multiplied. Large foot print tires are also prone to rutting caused by uneven road surfaces created by large trucks. Moving left to the hammer lane will eliminate this type of road feel. I suspect GM addressed the rutting problem in the later C4's by reducing front rim width by one inch to 8.5.

With correct caster settings the vehicle should feel planted at speed provided camber & toe settings are in spec.

Tire brand and age also enter into the equation.

GL
Reply
Old Apr 14, 2012 | 02:21 PM
  #10  
scottermis's Avatar
scottermis
Thread Starter
Advanced
 
Joined: Dec 2011
Posts: 57
Likes: 0
From: Edmond OK
Default

Originally Posted by Churchkey
I would keep the soft springs.

The front running short track pavement oval cars use soft springs, good shocks & large sway bars.

Suggest checking the front wheel alignment to insure there is enough caster. Light caster settings will give a loose front end feel at speed. On vehicles that have tires with a large foot print like our Vettes the loose feed back feel is multiplied. Large foot print tires are also prone to rutting caused by uneven road surfaces created by large trucks. Moving left to the hammer lane will eliminate this type of road feel. I suspect GM addressed the rutting problem in the later C4's by reducing front rim width by one inch to 8.5.

With correct caster settings the vehicle should feel planted at speed provided camber & toe settings are in spec.

Tire brand and age also enter into the equation.

GL


I just put a new set of NITTO NT555's on it all the way around but it was doing it before the new shoes. After measuring the front sway bar it is indeed a 24mm so i ordered a 29mm from addco with new poly bushings. I bet that fixes it ! Thanks you guys for all your input!!!!
Reply

Get notified of new replies

To Suspension question





All times are GMT -4. The time now is 04:15 AM.

story-0
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

Slideshow: From C1 to C8 we compare every Corvette generation by the numbers.

By Joe Kucinski | 2026-05-12 16:54:12


VIEW MORE
story-1
8 Coolest Corvette Pace Cars (and Replicas) of All Time

Slideshow: Some Corvette pace cars became collectible legends, while others perfectly captured the look and attitude of their era.

By Verdad Gallardo | 2026-05-11 09:50:51


VIEW MORE
story-2
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)

Slideshow: Ranking the top 10 Corvette engines by torque output.

By Joe Kucinski | 2026-05-05 11:58:09


VIEW MORE
story-3
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!

Slideshow: A Corvette pace car nearly matching IndyCar speeds sounds exaggerated, until you look at the numbers.

By Verdad Gallardo | 2026-05-04 20:03:36


VIEW MORE
story-4
Top 10 Corvettes Coming to Mecum Indy 2026!

Among a rather large group of them.

By Brett Foote | 2026-05-04 13:56:44


VIEW MORE
story-5
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!

Slideshow: the top 10 things Corvette owners want in the C9 Corvette

By Michael S. Palmer | 2026-04-30 12:41:15


VIEW MORE
story-6
10 Revolutionary 'Corvette Firsts' Most People Don't Know

Slideshow: 10 Important Corvette 'firsts' that every fan should know.

By Joe Kucinski | 2026-04-29 17:02:16


VIEW MORE
story-7
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

Slideshow: Should you buy a 2020-2026 Corvette or wait for 2027?

By Michael S. Palmer | 2026-04-22 10:08:58


VIEW MORE
story-8
2027 Corvette vs The World: Every C8 vs Its Closest Competitor

Slideshow: 2027 Corvette lineup vs the world.

By Joe Kucinski | 2026-04-24 16:12:42


VIEW MORE
story-9
10 Most Common Corvette Problems of the Last 20 Years!

Slideshow: 10 major Corvette problems from the last 20 years.

By Joe Kucinski | 2026-04-14 16:37:05


VIEW MORE