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!
1991 MX5

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.



Terry
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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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