Stock spring rates

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jerrah
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Stock spring rates

Postby jerrah » Wed Jul 11, 2012 12:32 pm

I currently have King springs that were fitted by the previous owner to Koni yellows. Even on maximum height setting I still find the car too low for most speed bumps and driveways.

Does anybody know the stock spring rates and/or King springs rates?

I could do with a bit firmer than the Kings springs when at the track and I'd like a little more ride height. If the stock springs are firmer than the Kings (which feel pretty soft) I can always lower the car through the adjustable perch to get the right height.
1991 MX5

93_Clubman
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Re: Stock spring rates

Postby 93_Clubman » Wed Jul 11, 2012 1:08 pm

NA6, NA8, & NA8 Clubman stock springs: 154/94 lbs/in
Believe conversion is: 55.9 lbs/in = 1 kg/mm => 154/94 lbs/in = 2.8/1.7 kgs/mm.

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jerrah
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Re: Stock spring rates

Postby jerrah » Wed Jul 11, 2012 2:27 pm

That can't be the same kg measurement that people are using for aftermarket springs or they're REALLY soft!
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sailaholic
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Re: Stock spring rates

Postby sailaholic » Wed Jul 11, 2012 2:40 pm

Rule of thumb for kings I was told was 30% stiffer than stock

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hks_kansei
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Re: Stock spring rates

Postby hks_kansei » Wed Jul 11, 2012 2:45 pm

jerrah wrote:That can't be the same kg measurement that people are using for aftermarket springs or they're REALLY soft!


It's about the same as what I remember the OEM ones being when I looked it up.
MX5 stock springs aren't really that stiff, you can compress them a good 10mm or so by hand.


For reference the Mazdaspeed springs in my NB are:
Front: 4.5kg/mm
Rear: 3.7kg/mm
1999 Mazda MX5 - 1989 Honda CT110 (for sale) - 1994 Mazda 626 wagon (GF's)

93_Clubman
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Re: Stock spring rates

Postby 93_Clubman » Wed Jul 11, 2012 6:23 pm

jerrah wrote:Does anybody know the stock spring rates and/or King springs rates?

Think the King spring online catalogue has their spring rates, or at least used to.

jerrah wrote:That can't be the same kg measurement that people are using for aftermarket springs or they're REALLY soft!

USDM spring specs:
manga_blue wrote:
Fatcat Motorsports wrote:NA
1990 164.17 96.94 Linear 59.0% No Red Dot Front, Blue Dot Rear Mazda - Manual Trans
1991 164.17 96.94 Linear 59.0% No Red Dot Front, Blue Dot Rear Mazda - Auto Trans
1991 153.52 93.53 Linear 60.9% No White Dot Front, Orange Dot Rear Mazda - Manual Trans
1992 164.17 96.94 Linear 59.0% No Red Dot Front, Blue Dot Rear Mazda - Auto Trans
1992 153.52 93.53 Linear 60.9% No White Dot Front, Orange Dot Rear Mazda - Manual Trans
1993 164.17 96.94 Linear 59.0% No Red Dot Front, Yellow Dot Rear Mazda - Auto Trans
1993 153.52 93.53 Linear 60.9% No White Dot Front, Green Dot Rear Mazda - Manual Trans
1994 153.52 96.94 Linear 63.1% No White Dot Front, Yellow Dot Rear Mazda - Auto Trans
1994 153.52 93.53 Linear 60.9% No Blue2 Dot Front, Green Dot Rear Mazda OEM 'R Package
1997 153 105 Linear 68.6% No Â
NB
1999 Stock 162 118 Linear 72.8% No Â
1999 Sport 168 130 Linear 77.4% No Â

posting.php?mode=quote&f=30&p=398739

tbro
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Re: Stock spring rates

Postby tbro » Wed Jul 11, 2012 6:56 pm

viewtopic.php?f=30&t=20996&hilit

Also depends how old springs are, late springs are progressive, so no real rate as such. The above is old type, get new std height rates they work well.



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noobee
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Re: Stock spring rates

Postby noobee » Wed Jul 11, 2012 9:47 pm

i found this somewhere(maybe even here,I can't remember) when I was looking for king spring info a while ago.


Quote:
Victor,

Part numbers,

KMFL-52 - 165-215lb/\" (progressive rate)
KMRL-53 - 105-160lb/\" (progressive rate)

Hope this is of some help.

Regards,


Kris Tarrant

Sales and Technical Services

IT Manager
KING SPRINGWORKS PTY LTD



KMFL-52 - Front NA springs
KMRL-53 - Rear NA springs

Mick

project.r.racing
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Re: Stock spring rates

Postby project.r.racing » Thu Jul 12, 2012 9:38 am

Kings are soft springs, especially their low ones. If you want some stiffer springs, then buy performance springs. Not cosmetic springs.

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jerrah
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Re: Stock spring rates

Postby jerrah » Thu Jul 12, 2012 10:31 am

Happy to. Kings were on the car when I bought it. What would you recommend?
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