rear spring rate
Turbo Mini Forums

so having had the rear coil overs on the car for a while , i need to get a problem with the left hand going coil bound on big bumps .
it is woulnd up a good inch further on the shock than the other side to get it level , and i assume its gone soft .
the q is ,what spring to go for ?
so far the data i have is that the old speedex beam kit ,from europa ,had 110lb progressive springs on it for a stock mini . i have some old auto grass mini shocks on the shelf ,and they are 75 lbs non rising rate .
i know a chap with 90's on his and he feels stiffer may be better (oh dear).
so i searched fori over the net ,and found

a) a chap had the same prob with one spring higher by an inch to get the car level ,and
b) talk of 125 springs being good .
so
for a nice firm ride and not too joggly (oh dear nic,,, calm! )
my plan at the mo is to measure the rate i have on there and go from there . im thinking 110 with the lighter car may be good ?

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

300lb rear springs do the job on The DON Robert!! LOL

er ...do they actually compress at all tom ?

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

Not particularly......!

this little bit from mini mania may be indicative ...

These should be replaced every 5-7 years depending on use and climate. Measured at the wheel, the spring rates at the static load position are 118 lb/in at the front and 98 lb/in at the rear. With three passengers and 50 lb of luggage, the loads per wheel at the same position are respectively 468 lb and 355 lb. These loads rise to 1,050 lb and 670 lb at full bump and fall to 240 lb and 100 lb when the rebound check is in operation. Early cones were SAE (UNF 1/2x20), all current cones now have metric threads (14mmX2)

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

On a more serious note we do have some 90lb rear springs for the DON that will be going in for Castle Combe.

Robert, how do you find your beam axel on the road? My subby will need replacing in the next 18 months or so and im tempted by the beam conversion.

Ive heard bad things about them for road use, but considerng mine is only driven to shows and nice days in the summer im tempted to give it a go?

https://www.facebook.com/pages/Fusion-Fabri..._homepage_panel

www.fusionfabs.co.uk



1/4mile in 13.2sec @ 111 terminal on 15psi

150lb for mine but 125lb if a road car.

On 5th Sep, 2011 Vegard said:
I stand corrected. You should know

tom thanks thats usefull .

matty , i find on the plus side , its smooth ride wize apart from the bottoming out ..and lost about 40 lbs off the car , negs are it brings more road rumble into the car from the wheels ,cos it is not rubber mounted .please come and ill take you out in it if you want .

scruffy ,thanks for that ,how heavy is your car ,? and did you do much experimentation with the rates ?
regards robert

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

Robert, it's funny but Rob H asked me this question last week.

The SPAX "low/track" kit runs 110 - 135 progressives (at fitted lengths) on the rear. This what I have on my car and they are fine on the road (so long as it's got some surface!!!).

My car isn't what you'd call light either as it has a full COBRA retrim (based around the Daytona 2 seats) 6pt bolt in cage etc. Was built to be a quick road car that you could do a few hundred miles in when you wanted to (used to commute to London from Evesham daily in her!!!)

Forgot to mention she is still running a full rear subframe too .... original beam got bent when some muppet hit her in London and I never got around to replacing it!

Edited by RogerM on 1st Sep, 2007.

Every day is a school day ...........

How fast and how expensive ...... the same question...

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

The 350lb ones that carl gave me might be a little harsh for the road lol!

1/4 Mile 14.3secs 96Mph Terminal 10psi of boost.


Fibreglass Parts? - http://www.tdkracing.co.uk/
Split Rims? - http://www.force-racing.co.uk/

Good question robert

I took my car to the super market yesterday and i was amazed how much better the shopping trolley handled

Im going to have to order some springs before combe

Nick-When you say 125lb for a road car is that due to comfort? or to allow for the rougher surfaces?
Im taking note of your experience and trust your judgement on it

excellent, thanks

I may even see about ordering some thinss week

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

I'd guess mine weighs about the same as your Rob ... maybe a little more 690kg ish.

The springs on mine are based around it's core usage .... fast road work. Is still good on track though ... normally pull out a lot of unecessary stuff out.

Every day is a school day ...........

How fast and how expensive ...... the same question...

no longer a series, but still 1.3 turbo.

75lb progressives aparently-theyre absolutly wrong for the car, they squash far to easily and eject the car off the ground as the boing back up

another point nic , is that a harder spring will stop the back dropping on launch ,so may reduce the 60 ft

thanks for that rog that is interesting ,maybe a 125 would be better .

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

so for lighter cars should you go for harder springs?

Im thinking of fast road use, and the odd track day

cheers

no nic .deff the lowr the weight on the spring
the softer it has to be ,,,all things being equal

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

Very bumpy Robert but I live in the race track capital of Bucks MK!

98% of the use of my Mini is on a circuit but is T&T & Insured

On 5th Sep, 2011 Vegard said:
I stand corrected. You should know

Out of interest Robert, have you checked the corner weights.

I found that although my car was level the hi-los were different side to side. This resulted in the weight of the car being mainly across one diagonal of the car. It looked right, but drove crap.

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

thats a very good point wil ,thanks . i havent got the kit to do that at the mo , but it does seem to drive well apart from the banging !

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM