spring rates

[renovationinnov]

ive just rang KING springs to find out how to get the correct rated springs
i was told they make to your requirements
my question is how to find this ??
i told them i was running jag front & rear ends with a corner weight of 250 to 260 kgs & asked how to work out a spring rate
the phone when silient .. to the reply is ' we need to know what inch /pound rebound rate is then we will make them to suit your requirements
s@#t what a waste of time !!
so does any one have a formula to work this out or is it a try /try again or do i just get a coil over shock [ avo's ]any help please
ROB

[boxhead]

Check out these.
https://www.box.com/shared/gcuutlsgbd

[mickmate]

I have changed a few Jag suspended cars back to stock E-type springs from heavy duty versions as they work well with cars of this weight. Coil springs on the back measure 7/16" dia wire standard with 1/2" for heavy duty, torsion bars measure .785" dia stock with .865" being the HD version.

[Rob. Smith]

Years ago I spoke to the manager at King springs and he admitted then that they didn't know how to make springs to a required rate. ( I hoped they might have learned by now) He admitted that they just copy the OEM wire sizes and just make them shorter or longer.
I ended up doing a lot of maths with an old engineering formula. There are several "calculators" on the net....much easier !

[Merv and Sharon]

I used QA1 springs from Summit. They have been better than the Kings I had. Rate depends on many things. How vertical are the mounts? Don't use AVOs.


There is this thread on spring rates from earlier this year: Spring rates

[Zedn]

Try calling eibach instead. I have heard they are really good to deal with.
Also talk to other people with your chassis.

[renovationinnov]

thanks for all your in put i think ill just buy some qa1'sfrom summit
after some more wasted phone calls to day i think most suppliers dont have an idea ether & just want to sellyou what ever
most common responce was " this is my best guess ; i'd probaly use bahbahbah "
& the second was " i heard these will probaly do the job ""

rob

[Outwest34au]

I've just been through the spring thing lately for the rear of mine. I needed to gain another inch for ground clearance rules and practicallity so called Kings fron work and was told to meausre the spring in situ then jack it under the body to desired height and measure again, send them the coilover in a box and they would figure the weight from it and sort it. They sounded like they had a fair clue what I wanted and how to do it.
The Cobra has monroe gt gas touring shocks on it that date way back but never been driven on but the design wouldn't allow for a qik fit adjustable thread kit to fit over the bottom mount pont or poly spacer discs.
Being good at pulling stuff apart I did that, after measuring current and desired spring lengths. After compressing the coil enough I could move the spring base plate and get to the external circlip that holds the base plate at height. Get that off and it all comes down to where the circlip groove is located.
I called Fulcrum who we deal with several times weekly and always find them good value for assistance, asked them about bilstiens, same deal as the monroes, the bilstien has one circlip groove also, but there is a jag guy somewhere who orders his with the groove 10mm different, but this also seemed too hard as the groove Maybe at the same spot.
I was just about to sling the coin and go the QA1's when a guy in town offered to lathe new circlip grooves, so we did 1 groove 15mm higher and 1 at 25mm higher which gives me a passable ground clearance. It's not the most efficient way probably, I don't yet know how the car will ride but that was also a reason I didn't want to spend up on suspension yet.
At the end of it all, $100 for the lathe work on 4 shocks. I had other options but this will get me plated.
The good bit is, if it rides OK and then I want it lowered a wee bit I just move the circlip to the extra new groove.

[Outwest34au]

Originally Posted by renovationinnov

thanks for all your in put i think ill just buy some qa1'sfrom summit
after some more wasted phone calls to day i think most suppliers dont have an idea ether & just want to sellyou what ever
most common responce was " this is my best guess ; i'd probaly use bahbahbah "
& the second was " i heard these will probaly do the job ""

rob

Rob, I'm hearing what you're saying, but mostly they are distributors.
I have always found that if a car is on road (so to speak) it's easier for a good suspension bloke to get it where you expect it.
I'd hate to see you spend a motza to have to do it again later.
I am however very very sure there are others out there brighter than me that can give you the answer in part numbers.

[Modena]

Best bet is to ask others with the same chassis as you, and even ride in their cars for a bit if possible, then modify from there. As you're running Jag front and rear I would think many more people on here would have chimed in with that they're running on their Jag setups. As far as brand goes any reputable brand should probably be ok (such as Eibach or QA1).

Personally I'm getting Hyperco springs, they are used and recommended by Penske. Hyperco make all the springs for F1 so I'm told, and many top teams in other motorsport. Welcome to Hyperco | High Performance Coil Springs & Suspension Components You can get them from NT Tyres in Adelaide.

Also you haven't mentioned what shocks you have?

[renovationinnov]

modena i have koni shocks for front & rear had monroes for both but sold them to a friend for there jag as they needed them yeserday so to speak
the koni's are stanard ride lenth for jag

[Merv and Sharon]

Rob, I played around with King Springs and even 'keeper springs' to ensure that on full droop they had correct/some tension. A critical factor is the length of the spring in relation to the shock and suspension travel. You want the shock to operate over most of its range, not be wound right up because the spring is too short.

There may also be a front to rear difference in spring and shock length, depending on your suspension set up. My springs are more vertical now than before and that changes the equation again. As Ben has said, I would have a chat with the guys who have the same suspension. I have my old King springs, if you want to play around with them.

If you don't want to deal with Summit, try The Car Shop in Moline. I found they were cheaper on many items and gave great service and advice. (High Performance Parts & Accessories - Car Shop Inc. )

[AC-460]

You also need to look at the size of your sway bars... the heavier the sway bar means you can back off slightly on your spring poundage...you need to get the right balance you need to look at the whole picture not just the pounds on the springs...Talk to someone with a similar car.....

[sjelby]

Rob, you dont need springs yet,
You need to get the car first.
LOL

[renovationinnov]

ah ah stan get back to your shed & do some work on yours

[sevenohms]

Anyone wanna go for a drive? HAHAHAHA

You both better get into the shed! HAHAHAHA

[renovationinnov]

well guys i.m no better off as i still after a size or product no# for coil springs for the front
as some have suggested i need to talk to members with the same chassis & now there is only 3 i know of myself , sjelby & sevenohms all have different front ends so !!!
HELP
ROB

[Magicalab]

Hi Not sure if you have your springs sorted yet, SA Springs in Aderlaide have off the shelf for Jag suspension on Cobras, I got mine and the quality is 1st Class and powder coated I think I paid $60 each for them, hope this helps! Mark.

[legenmetals]

I'm using 300 lb. springs on my Contemporary with Jaguar rear set up. Four shocks on the rear. Keep in mind the more angle that your shocks are at the higher the spring rated needed. I used Qa1 adjustable shocks with spring adjustment.Bought everything from Summit Racing.