Spring Rate for Stock Leafs...
Thread Starter
Pro
Joined: Aug 2005
Posts: 503
Likes: 50
From: Bradenton, FL
Spring Rate for Stock Leafs...
Does anyone know what the equivalent spring rate is for the front and back transverse leaf springs on a 2003 vert? Can't find that data in the shop manual or online...
I picked up some Alden American coil overs and finally got them installed last weekend... I think I've got the back reasonably dialed in, but the fronts feel horrendous. Like driving Fred Flintstone's ride... Front spring rate = 550lbs and rear spring rate = 500 lbs... Wondering is the stock leafs are a bit more forgiving...
I picked up some Alden American coil overs and finally got them installed last weekend... I think I've got the back reasonably dialed in, but the fronts feel horrendous. Like driving Fred Flintstone's ride... Front spring rate = 550lbs and rear spring rate = 500 lbs... Wondering is the stock leafs are a bit more forgiving...
Thread Starter
Pro
Joined: Aug 2005
Posts: 503
Likes: 50
From: Bradenton, FL
An entire Forum Thread on the subject of spring rates from back in 2010:
http://forums.corvetteforum.com/1574267563-post6.html
Just need to know the RPO number of the spring setup on your car. Starting in model year 1999 the RPO sticker is inside the glove box door. Prior years the sticker was on the bottom side of the drivers side rear cubby hole cover.
http://forums.corvetteforum.com/1574267563-post6.html
Just need to know the RPO number of the spring setup on your car. Starting in model year 1999 the RPO sticker is inside the glove box door. Prior years the sticker was on the bottom side of the drivers side rear cubby hole cover.
I have the FE1 suspension. According to this thread the spring rates for the front are 440lbs. This seems quite a bit stiffer than 550 lbs. I know as much about suspension as I do docking the space shuttle... Would that increase (~110lbs) change the road feel that drastically?
With increase of 25% in stiffness, I would think so, but looking for a more informed opinion...
I gotta stop the fillings from rattling loose in my mouth.
Drifting
Joined: Dec 2010
Posts: 1,776
Likes: 500
From: West Seneca NY
I had this posted in another thread on coilovers for C6, also unless you are tracking I would think you want softer spring in front.
Did you order the shorter coilover for the front from Aldan? if not and you lowered too much you may be riding on the bump stops.
Springs:
C5 Z06: 526# Front, 714# Rear
C6 Z06: 531# Front, 782# Rear
C6 Z51: 526# Front, 645# Rear
T1 (C6): 582# Front, 850# Rear
C6 Base: 420# Front, 657# Rear (VBP: 400-420 F / 600-620 R)
T1 (C5): 582# Front, 793# Rear
Pfadt Coil-overs: 425# Front, 575# Rear (Remember: Wheel rates!)
Hyperco HPS (Street): 565# Front (12405HPS), #765 Rear (12406HPS)
Hyperco HPT (Track/Solo): 625# Front (12407HPT), #850 Rear (12408HPT)
VBP Sport 990# Front, 650# Rear
VBP Extreme 1050# Front, 855# Rear
Did you order the shorter coilover for the front from Aldan? if not and you lowered too much you may be riding on the bump stops.
Springs:
C5 Z06: 526# Front, 714# Rear
C6 Z06: 531# Front, 782# Rear
C6 Z51: 526# Front, 645# Rear
T1 (C6): 582# Front, 850# Rear
C6 Base: 420# Front, 657# Rear (VBP: 400-420 F / 600-620 R)
T1 (C5): 582# Front, 793# Rear
Pfadt Coil-overs: 425# Front, 575# Rear (Remember: Wheel rates!)
Hyperco HPS (Street): 565# Front (12405HPS), #765 Rear (12406HPS)
Hyperco HPT (Track/Solo): 625# Front (12407HPT), #850 Rear (12408HPT)
VBP Sport 990# Front, 650# Rear
VBP Extreme 1050# Front, 855# Rear
Racer
Joined: Aug 2015
Posts: 316
Likes: 45
From: Sarasota
I may be wrong here, but spring rates for leaf springs are not 1:1 with spring rates for coil overs.
C5 Base: 440# Front, 577 # Rear
C5 Z51: 525# Front, 634# Rear
C5 Z06: 526# Front, 714# Rear
T1 (C5): 582# 12480063 Front, 793# Rear
My initial set up:
VBP Composite Sport Front Spring Rate: 903
C5Z06 Rear Spring – Rate: 714
C6ZR1 front swaybar – 33mm
C6Z51 rear swaybar – 25.4mm
C6Z06 Shocks front and rear
When my VBP front spring cracked I installed Pfadt coilovers on the front with 500lb springs. The car behaved very well on the track with just a little understeer; however, the ride did get a little harsher.
I don't understand going with springs in the rear that are rated less than those in the front. The 425/575 or maybe 425/500 might give you the ride that you are looking for.
From Aldan's web page for 2003 Corvette:
Adjustable Ride Height: 0.0-2.0 in. lowered Front & Rear
Single Adjustable Coilovers
Spring Rate: 500 lbs./in. front, 550 lbs./in. rear
Coilover Kit Position: Front & Rear.
I think you have the springs installed backward.
Marc
C5 Base: 440# Front, 577 # Rear
C5 Z51: 525# Front, 634# Rear
C5 Z06: 526# Front, 714# Rear
T1 (C5): 582# 12480063 Front, 793# Rear
My initial set up:
VBP Composite Sport Front Spring Rate: 903
C5Z06 Rear Spring – Rate: 714
C6ZR1 front swaybar – 33mm
C6Z51 rear swaybar – 25.4mm
C6Z06 Shocks front and rear
When my VBP front spring cracked I installed Pfadt coilovers on the front with 500lb springs. The car behaved very well on the track with just a little understeer; however, the ride did get a little harsher.
I don't understand going with springs in the rear that are rated less than those in the front. The 425/575 or maybe 425/500 might give you the ride that you are looking for.
From Aldan's web page for 2003 Corvette:
Adjustable Ride Height: 0.0-2.0 in. lowered Front & Rear
Single Adjustable Coilovers
Spring Rate: 500 lbs./in. front, 550 lbs./in. rear
Coilover Kit Position: Front & Rear.
I think you have the springs installed backward.
Marc
Last edited by marc a; Mar 3, 2018 at 12:22 AM.
Thread Starter
Pro
Joined: Aug 2005
Posts: 503
Likes: 50
From: Bradenton, FL
I had this posted in another thread on coilovers for C6, also unless you are tracking I would think you want softer spring in front.
Did you order the shorter coilover for the front from Aldan? if not and you lowered too much you may be riding on the bump stops.
Springs:
C5 Z06: 526# Front, 714# Rear
C6 Z06: 531# Front, 782# Rear
C6 Z51: 526# Front, 645# Rear
T1 (C6): 582# Front, 850# Rear
C6 Base: 420# Front, 657# Rear (VBP: 400-420 F / 600-620 R)
T1 (C5): 582# Front, 793# Rear
Pfadt Coil-overs: 425# Front, 575# Rear (Remember: Wheel rates!)
Hyperco HPS (Street): 565# Front (12405HPS), #765 Rear (12406HPS)
Hyperco HPT (Track/Solo): 625# Front (12407HPT), #850 Rear (12408HPT)
VBP Sport 990# Front, 650# Rear
VBP Extreme 1050# Front, 855# Rear
Did you order the shorter coilover for the front from Aldan? if not and you lowered too much you may be riding on the bump stops.
Springs:
C5 Z06: 526# Front, 714# Rear
C6 Z06: 531# Front, 782# Rear
C6 Z51: 526# Front, 645# Rear
T1 (C6): 582# Front, 850# Rear
C6 Base: 420# Front, 657# Rear (VBP: 400-420 F / 600-620 R)
T1 (C5): 582# Front, 793# Rear
Pfadt Coil-overs: 425# Front, 575# Rear (Remember: Wheel rates!)
Hyperco HPS (Street): 565# Front (12405HPS), #765 Rear (12406HPS)
Hyperco HPT (Track/Solo): 625# Front (12407HPT), #850 Rear (12408HPT)
VBP Sport 990# Front, 650# Rear
VBP Extreme 1050# Front, 855# Rear
I may be wrong here, but spring rates for leaf springs are not 1:1 with spring rates for coil overs.
C5 Base: 440# Front, 577 # Rear
C5 Z51: 525# Front, 634# Rear
C5 Z06: 526# Front, 714# Rear
T1 (C5): 582# 12480063 Front, 793# Rear
My initial set up:
VBP Composite Sport Front Spring Rate: 903
C5Z06 Rear Spring – Rate: 714
C6ZR1 front swaybar – 33mm
C6Z51 rear swaybar – 25.4mm
C6Z06 Shocks front and rear
When my VBP front spring cracked I installed Pfadt coilovers on the front with 500lb springs. The car behaved very well on the track with just a little understeer; however, the ride did get a little harsher.
I don't understand going with springs in the rear that are rated less than those in the front. The 425/575 or maybe 425/500 might give you the ride that you are looking for.
From Aldan's web page for 2003 Corvette:
Adjustable Ride Height: 0.0-2.0 in. lowered Front & Rear
Single Adjustable Coilovers
Spring Rate: 500 lbs./in. front, 550 lbs./in. rear
Coilover Kit Position: Front & Rear.
I think you have the springs installed backward.
Marc
C5 Base: 440# Front, 577 # Rear
C5 Z51: 525# Front, 634# Rear
C5 Z06: 526# Front, 714# Rear
T1 (C5): 582# 12480063 Front, 793# Rear
My initial set up:
VBP Composite Sport Front Spring Rate: 903
C5Z06 Rear Spring – Rate: 714
C6ZR1 front swaybar – 33mm
C6Z51 rear swaybar – 25.4mm
C6Z06 Shocks front and rear
When my VBP front spring cracked I installed Pfadt coilovers on the front with 500lb springs. The car behaved very well on the track with just a little understeer; however, the ride did get a little harsher.
I don't understand going with springs in the rear that are rated less than those in the front. The 425/575 or maybe 425/500 might give you the ride that you are looking for.
From Aldan's web page for 2003 Corvette:
Adjustable Ride Height: 0.0-2.0 in. lowered Front & Rear
Single Adjustable Coilovers
Spring Rate: 500 lbs./in. front, 550 lbs./in. rear
Coilover Kit Position: Front & Rear.
I think you have the springs installed backward.
Marc
In the end I probably shouldn't have gone with the coil overs. I was looking to add newer tech and needed to change my shocks anyway. So I thought that this would be a good, cost effective compromise. I spoke with Mark at TPS. I am going to swap the front springs with 450s and give it a whirl.
Racer
Joined: Aug 2015
Posts: 316
Likes: 45
From: Sarasota
With the softer springs you will get more shock travel so you might want to start with only enough preload to keep the spring in the top hat when the front wheel is off the ground and adjust from there.
Last edited by marc a; Mar 4, 2018 at 10:30 AM.
Drifting
Joined: Dec 2010
Posts: 1,776
Likes: 500
From: West Seneca NY
I am right now installing a set of BC Racing coilovers, what came with them is 7K/10K or 392/560 length 6.7" & 6" I did an upgrade to Hyperco springs running 400/550 both 7" springs & plenty of clearance in the rear, I marked my shock shaft for 50% & 40% travel line at ride height, some recommend 45% so I knew exactly where I was at ride height, and could add more preload to adjust the ride height & stay within those parameters. I haven't driven & tuned it yet but hopefully my front rate will not be too soft.
On the Aldan web site the rates for Corvette are listed as 500/550 F/R if you like a softer ride I think the 450 front & keep the 500 on the rear would be fine.
And as I did, unless your not fussy like me is mark your shock & set your preload so you have a little more shock travel for compression, you will raise the car by doing that, having an adjustable shock base F & R makes that easier to put your ride height back where you want it, not sure why Aldan only has it on the rear, was one of my reasons to look at other options.
And yes spring rates as mentioned above are not the same for Leafs vs Coilovers.
On the Aldan web site the rates for Corvette are listed as 500/550 F/R if you like a softer ride I think the 450 front & keep the 500 on the rear would be fine.
And as I did, unless your not fussy like me is mark your shock & set your preload so you have a little more shock travel for compression, you will raise the car by doing that, having an adjustable shock base F & R makes that easier to put your ride height back where you want it, not sure why Aldan only has it on the rear, was one of my reasons to look at other options.
And yes spring rates as mentioned above are not the same for Leafs vs Coilovers.
Last edited by 6speedsteve; Mar 4, 2018 at 09:56 AM.
Thread Starter
Pro
Joined: Aug 2005
Posts: 503
Likes: 50
From: Bradenton, FL
I am right now installing a set of BC Racing coilovers, what came with them is 7K/10K or 392/560 length 6.7" & 6" I did an upgrade to Hyperco springs running 400/550 both 7" springs & plenty of clearance in the rear, I marked my shock shaft for 50% & 40% travel line at ride height, some recommend 45% so I knew exactly where I was at ride height, and could add more preload to adjust the ride height & stay within those parameters. I haven't driven & tuned it yet but hopefully my front rate will not be too soft.
On the Aldan web site the rates for Corvette are listed as 500/550 F/R if you like a softer ride I think the 450 front & keep the 500 on the rear would be fine.
And as I did, unless your not fussy like me is mark your shock & set your preload so you have a little more shock travel for compression, you will raise the car by doing that, having an adjustable shock base F & R makes that easier to put your ride height back where you want it, not sure why Aldan only has it on the rear, was one of my reasons to look at other options.
And yes spring rates as mentioned above are not the same for Leafs vs Coilovers.
On the Aldan web site the rates for Corvette are listed as 500/550 F/R if you like a softer ride I think the 450 front & keep the 500 on the rear would be fine.
And as I did, unless your not fussy like me is mark your shock & set your preload so you have a little more shock travel for compression, you will raise the car by doing that, having an adjustable shock base F & R makes that easier to put your ride height back where you want it, not sure why Aldan only has it on the rear, was one of my reasons to look at other options.
And yes spring rates as mentioned above are not the same for Leafs vs Coilovers.
With respect to the spring rates not being the same for coil versus leaf... of course. It couldn't be that easy of a comparison, could it...
The folks at TPS (who sold me the shocks) told me that they found the 550/500 F/R to be the best set up based on their testing so that was the way they were shipping them. I talked to Mike at TPS on Friday. He was all good on sending out a different set of springs for my liking, so that was really cool.
I started the front with the recommended 1/2 inch preload and I really think it was bottoming. Over the weekend I added an additional 1/2 inch of preload and that made a world of difference. And jacked my car up like a Jeep! Alden has agreed to send out a pair of their short front shocks (1 inch shorter) for me to swap out and try.
So that is where I am right now. I am REALLY curious to hear about your 400 fronts and how soft they might be. I may ask Alden to send the shocks with springs as well for me to test...
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Drifting
Joined: Dec 2010
Posts: 1,776
Likes: 500
From: West Seneca NY
Thanks for the detail Steve. Let's see if I can digest it...
With respect to the spring rates not being the same for coil versus leaf... of course. It couldn't be that easy of a comparison, could it...
The folks at TPS (who sold me the shocks) told me that they found the 550/500 F/R to be the best set up based on their testing so that was the way they were shipping them. I talked to Mike at TPS on Friday. He was all good on sending out a different set of springs for my liking, so that was really cool.
I started the front with the recommended 1/2 inch preload and I really think it was bottoming. Over the weekend I added an additional 1/2 inch of preload and that made a world of difference. And jacked my car up like a Jeep! Alden has agreed to send out a pair of their short front shocks (1 inch shorter) for me to swap out and try.
So that is where I am right now. I am REALLY curious to hear about your 400 fronts and how soft they might be. I may ask Alden to send the shocks with springs as well for me to test...
With respect to the spring rates not being the same for coil versus leaf... of course. It couldn't be that easy of a comparison, could it...
The folks at TPS (who sold me the shocks) told me that they found the 550/500 F/R to be the best set up based on their testing so that was the way they were shipping them. I talked to Mike at TPS on Friday. He was all good on sending out a different set of springs for my liking, so that was really cool.
I started the front with the recommended 1/2 inch preload and I really think it was bottoming. Over the weekend I added an additional 1/2 inch of preload and that made a world of difference. And jacked my car up like a Jeep! Alden has agreed to send out a pair of their short front shocks (1 inch shorter) for me to swap out and try.
So that is where I am right now. I am REALLY curious to hear about your 400 fronts and how soft they might be. I may ask Alden to send the shocks with springs as well for me to test...