leaf springs rates
Thread Starter
Melting Slicks
Joined: Jan 2002
Posts: 2,238
Likes: 4
From: Milan
leaf springs rates
There is a link (i don/t remember where) where there are all C4 suspension specs divided by year and RPO codes.
Spring rates are expressed on N/mm (?''!$??).
often this rate is in Lb.
Many vendors sells 2 kind of rear springs (one called standard and the other called "sport"). I found on the ZIP catalog that the rear "sport" spring is 450 Lb.
The spring i'm using now (It comes from a 96 is 26.00 N/mm -referring to the link) is very soft and I want to know if the 450 lB is stiffer and How more is stiff.
Thanks
-Beppe-
Spring rates are expressed on N/mm (?''!$??).
often this rate is in Lb.
Many vendors sells 2 kind of rear springs (one called standard and the other called "sport"). I found on the ZIP catalog that the rear "sport" spring is 450 Lb.
The spring i'm using now (It comes from a 96 is 26.00 N/mm -referring to the link) is very soft and I want to know if the 450 lB is stiffer and How more is stiff.
Thanks
-Beppe-
Burning Brakes
Joined: Aug 2001
Posts: 1,238
Likes: 0
From: walled lake MI
i guess you're talking about this:
http://corvetteactioncenter.com/tech/c4/susp_chart.html
1 lb force = 4.45 N
1 in -> 25.4 mm
450 lb/in = (450)(4.45)/(25.4) = 78.8 N/mm
(i think i did that right....
)
that brings you in the realm of the infamous 84 Z51 rate. might want to check with someone if you need to change out your shocks for a stiffer one.
http://corvetteactioncenter.com/tech/c4/susp_chart.html
1 lb force = 4.45 N
1 in -> 25.4 mm
450 lb/in = (450)(4.45)/(25.4) = 78.8 N/mm
(i think i did that right....
)that brings you in the realm of the infamous 84 Z51 rate. might want to check with someone if you need to change out your shocks for a stiffer one.
Last edited by tempest; Jul 22, 2004 at 01:32 PM.
Burning Brakes
Joined: Dec 2002
Posts: 1,199
Likes: 4
From: Cairns Australia
Don't throw that spring away, conv90 - it's exactly the one I'm looking for!!!! What is the 3 letter prefix on it ?
I have an 88 with 93.1 fronts and 39.9 rears, as per the Hib Halverson chart. I discovered a few weeks ago that my suspension is fine on good roads in my capital city - I drove for 4 days and thought something had eased in the suspension - on the drive home the road got worse and worse - I've gotta get softer springs before my car falls to pieces around me -- I'm also looking for the 94-96 soft front spring rated at 60N/mm
tempest, your maths may be wrong somewhere- the stock 90 front springs are rated at either 93.1 or 115.5N/mm - although there is a 73.2 spring on certain models from 1992 on - perhaps thats the one conv90 has.
Please let me know if you want to do a swap or sell that soft rear spring
S'nut
I have an 88 with 93.1 fronts and 39.9 rears, as per the Hib Halverson chart. I discovered a few weeks ago that my suspension is fine on good roads in my capital city - I drove for 4 days and thought something had eased in the suspension - on the drive home the road got worse and worse - I've gotta get softer springs before my car falls to pieces around me -- I'm also looking for the 94-96 soft front spring rated at 60N/mm
tempest, your maths may be wrong somewhere- the stock 90 front springs are rated at either 93.1 or 115.5N/mm - although there is a 73.2 spring on certain models from 1992 on - perhaps thats the one conv90 has.
Please let me know if you want to do a swap or sell that soft rear spring
S'nut
Thread Starter
Melting Slicks
Joined: Jan 2002
Posts: 2,238
Likes: 4
From: Milan
Originally Posted by Stingraynut
Don't throw that spring away, conv90 - it's exactly the one I'm looking for!!!! What is the 3 letter prefix on it ?
I have an 88 with 93.1 fronts and 39.9 rears, as per the Hib Halverson chart. I discovered a few weeks ago that my suspension is fine on good roads in my capital city - I drove for 4 days and thought something had eased in the suspension - on the drive home the road got worse and worse - I've gotta get softer springs before my car falls to pieces around me -- I'm also looking for the 94-96 soft front spring rated at 60N/mm
tempest, your maths may be wrong somewhere- the stock 90 front springs are rated at either 93.1 or 115.5N/mm - although there is a 73.2 spring on certain models from 1992 on - perhaps thats the one conv90 has.
Please let me know if you want to do a swap or sell that soft rear spring
S'nut
I have an 88 with 93.1 fronts and 39.9 rears, as per the Hib Halverson chart. I discovered a few weeks ago that my suspension is fine on good roads in my capital city - I drove for 4 days and thought something had eased in the suspension - on the drive home the road got worse and worse - I've gotta get softer springs before my car falls to pieces around me -- I'm also looking for the 94-96 soft front spring rated at 60N/mm
tempest, your maths may be wrong somewhere- the stock 90 front springs are rated at either 93.1 or 115.5N/mm - although there is a 73.2 spring on certain models from 1992 on - perhaps thats the one conv90 has.
Please let me know if you want to do a swap or sell that soft rear spring
S'nut
I do not remember the code. I remember that when I checked it (something like RTZ or similar) someone in the forum said me it was the weakest one on the 96 production.
Tempest's caculations were referred to the REAR spring. I agree with you that the Front is 93.1.
I was using the Rear Stock spring in my car (supposed to be the 39.9 N/mm) and I really liked it. When it developped a little crack in the middle I searched for a replacement one. I found only this really weak one (I think its the 26 N/mm) so I'm looking for a stiffer one. The max rate I want is the rear Z51 with 57 N/mm.
The corvetteactioncenter link is far to be perfect...
They say that my rear Sway bar is 24mm (I measured and it is 22 mm)
-Beppe-
Burning Brakes
Joined: Dec 2002
Posts: 1,199
Likes: 4
From: Cairns Australia
Beppe, I'm in Australia ! - is the spring currently fitted to your car or have you removed it? I'm not sure what the postage would cost, do you have any idea ?
I haven't been able to find the code for the soft front spring yet, but the rear code should be RHZ - according to info I got on this forum recently - send me an email at make_contact_@hotmail.com
S'nut
I haven't been able to find the code for the soft front spring yet, but the rear code should be RHZ - according to info I got on this forum recently - send me an email at make_contact_@hotmail.com
S'nut
Burning Brakes
Joined: Aug 2001
Posts: 1,238
Likes: 0
From: walled lake MI
Originally Posted by Stingraynut
tempest, your maths may be wrong somewhere- the stock 90 front springs are rated at either 93.1 or 115.5N/mm - although there is a 73.2 spring on certain models from 1992 on - perhaps thats the one conv90 has.
Le Mans Master
Joined: Jan 2004
Posts: 7,276
Likes: 3
From: Why are there squished peanut butter cups in my underware?
I thought I answered that for you before.
http://forums.corvetteforum.com/showthread.php?t=864696
BTW, the 450lb rate spring is an aftermarket rate, it is not a factory rate.
Originally Posted by Stingraynut
I haven't been able to find the code for the soft front spring yet
S'nut
S'nut
BTW, the 450lb rate spring is an aftermarket rate, it is not a factory rate.
Burning Brakes
Joined: Dec 2002
Posts: 1,199
Likes: 4
From: Cairns Australia
Hi Z07 freak, No, you could only give the rear 3 letter prefix (for which many thanks, half the unknown is known!) here's your reply to me -
"Stingraynut,
26.0 rears are code RHZ
The code for the 60.0 fronts is a little tricky. I believe it will have either code HA or JA. The 60.0 front spring is the only C4 spring I can not confirm 100%."
and here's the link to the post, http://forums.corvetteforum.com/showthread.php?t=864696
you'll see I replied there and asked re source for the front spring codes -
The 60N/mm front springs were used with various configurations so it's extra difficult to ENSURE that I get the correct spring - no point shipping to Australia, paying import duty, sales tax and getting them fitted only to find I got the wrong spring !
I'd bet that the 60N/mm spring has one 3 letter code for all configurations. Anyone know how I can find it ?
S'nut
"Stingraynut,
26.0 rears are code RHZ
The code for the 60.0 fronts is a little tricky. I believe it will have either code HA or JA. The 60.0 front spring is the only C4 spring I can not confirm 100%."
and here's the link to the post, http://forums.corvetteforum.com/showthread.php?t=864696
you'll see I replied there and asked re source for the front spring codes -
The 60N/mm front springs were used with various configurations so it's extra difficult to ENSURE that I get the correct spring - no point shipping to Australia, paying import duty, sales tax and getting them fitted only to find I got the wrong spring !
I'd bet that the 60N/mm spring has one 3 letter code for all configurations. Anyone know how I can find it ?
S'nut
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Le Mans Master
Joined: Jan 2004
Posts: 7,276
Likes: 3
From: Why are there squished peanut butter cups in my underware?
S'nut
I'll clearify my answer. When I say I'm not 100% sure, I mean I don't know which one is the early production and which one is the late production. The 60.0 rate spring will have either HA or JA code stamped on it. There is no three letter digit code for the 60.0 spring.
I'll clearify my answer. When I say I'm not 100% sure, I mean I don't know which one is the early production and which one is the late production. The 60.0 rate spring will have either HA or JA code stamped on it. There is no three letter digit code for the 60.0 spring.
Burning Brakes
Joined: Dec 2002
Posts: 1,199
Likes: 4
From: Cairns Australia
Sorry Z07 freak, I misread your answer - and the 2 letter code also made me misunderstand and think there was another letter to come.
Thanks for explaining - my friends in the city say they have to type slowly when they email me ;-)
S'nut
Thanks for explaining - my friends in the city say they have to type slowly when they email me ;-)
S'nut
