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Can anyone tell me what the stock spring rates are for a 1992 NA6 in KG please ?

Stock 91-93 is 154/94 lb/in. Conversion factor is 55.9 lb/in = 1 kg/mm. So that makes it 2.8/1.7 Kg/mm

Also seriously recommend that you study Shaikh's suspension bible well before you do any spring or sway bar changes.
http://www.fatcatmotorsports.com/FRC_TU ... TORIAL.htm

manga_blue wrote:Stock 91-93 is 154/94 lb/in.

Same as NA8 then according to this:
viewtopic.php?f=30&t=30644

Thanks for the replys everyone ,

I'm now puzzled as I see that the lowest (and rarest) spring rates I have seen posted in aftermarket set ups seem to be 6 and 5 Kg F/R or approx two and three times the factory rates respectivley and that seems to be mainly for street , with street/track cars going anything up to 10/9 kg F/ R ,

I cannot think that an 8/7 kg F/R set up can possibly be either comfortable or efficient for good ole bumpy road street use and I'm talking ram raid and escape use not just taking Gran to the bingo , and I have reservations about 7/6 s as well.

I have had a read of Shaikh's tables and explanations but unfortunately don't have the basic knowledge to actualy translate them an overall hardware picture in my head though the basic messages on sway bars is clear..

My instinct given the factory rates would be to go for street spring set ups of 4.2 and 2.5 KG F/R respectively with a lowering of 20mm max F/R to give best stickability (street) and leave the factory sway bars alone.

Obviously I'm missing something big time --but what ?

A 9/8kg combo would be very oversteery, 5s like a 3/2 combo. So 1.5/1, 3/2, 6/4, 9/6 etc.

I run a 9/7 which is a little tiny bit oversteery for most, I like to turn the wheel x amount and then trim the car with the pedals.

I wish that I had multiple bars and springs to swap and play with so I could experiment but at the moment I dont so truth is, I ddont really have any authority on the matter.

Dann

You need to have a ride in a few cars with different spring rates. Personal preferences for stiffness and body roll comes into it a lot.

From my perspective I found the stock rates to be far too soft, even for street use. The missus said it was so floaty it was like a yank tank and it made her carsick.

Then I swapped to 5/4 Kg/mm Teins and I thought it was OK as a street /track compromise and it worked well with 20/0mm (57.1% FRC), 22/11 (57.9%) and 24/16 (55.9%) sway combos (with 22/11 being best) but manga-scarlet still found it uncomfortably soft.

Now I run 10/7 with either 0/0 (53.5) or 24/16 (53.6%) sway combos, with 0/0 being better. It's a bit jarring at low speeds around town but super comfy at speed on the highways. Grip is pretty amazing without the bars and it handles rough roads, dirt roads and bumpy tracks better. It's too skittish for public roads with bars. manga_scarlet is happy now that it's no longer floaty.

That 55-57% range worked best for the softer springs. 53% is best for firmer. In both cases it means neutral to slight oversteer with my driving style.

So Basho,
What are you trying to achieve.
Do you want a lowered car, softer riding, replace everything cause you can???????

I've been through all of this in the past in a previous Clubby.

Have a read and see if that is what you want??

viewtopic.php?f=30&t=30330&start=30

Terry

tbro wrote:So Basho,
What are you trying to achieve.
Do you want a lowered car, softer riding, replace everything cause you can???????
I've been through all of this in the past in a previous Clubby.
Have a read and see if that is what you want??
viewtopic.php?f=30&t=30330&start=30Terry

Hi Terry thanks for the reply,

I'm after a better and flatter ride and improved steering characteristics with the minimum of fuss or modification , I think a slight lowering will be part of the process.

The car currently has mind numbingly heavy steering and corresponding suspension characteristics with the stock set up but as I haven't dríven another one thats 20 years old that still has the origional suspension I have no scale of comparison to know whether this is normal or not , I would believe it is.

This is an observation , not a criticism, I have a very bad back and this set up is providing the best excercise I have found to date.

The car had a wheel alignment at Action Tyres who have done excellent work with all my previous cars and the steering is a swag load better for it and a new set of 15X7 34 offset 6ULS with new SIMEX SM8000 195X50 these made no difference to the steering wieght but did improve the overall handling feel.

The car is not destined for the track atall

Mike-(emx005) was kind enough to let me have a spin in his NA yesterday which has 8 and 6 kg Yellowspeed pro sport 's fitted and the difference is mind bogling with the steering much more alive to feel and the ride comfortable the car is also running aftermarket wheels .

As it would appear coilovers will produce the result I'm after this is the way I will be going the only thing I need to sort out is the spring weight .

Given what is essentialy a 3 - 2 kg OE rate and in light of the ride in Mikes car I drove yesterday and the fact I don't want to mess any further with the factory set up than I need to I'm thinking that a 5 - 4 or a 6 - 5 F/R Kg spring rate and a 15 to 20mm lowering with the damper adjustment tuned in for ride should give me what I'm after.

I'm still not confident on my spring rates logic however.

6-5 will be oversteery. You will never notice it dawdling around town, but in the wet and in an emergency situation you will.

Dann

NitroDann wrote:6-5 will be oversteery. You will never notice it dawdling around town, but in the wet and in an emergency situation you will. Dann

Thanks Dann, what would you recomend ?

The penny might have just dropped--if the oe rate is 3 / 2 near as dammit is to sweraing that woud put increases at a multiple of 1 front and .66 rear ?

If thats the case then to increase spring rates but stay with the factory balance overall a front rate of 5 would mean a rear rate of 3.3 and further 6 Front would be 3.96 Rear and so on ?

Am I anywhere near on the money ??

Yes 3/2.

You stick to a 3/2 spring rate, and trim it to your liking with swaybars.

Adjustable sways are popular because you can change the roll couple without removing anything.

If you buy 6/4s, and whiteline adjustables the centre/centre settings on the sway bars are the same stiffness ratio as stock, just stiffer, so then you can adjust the sways to make small trims to front/rear roll stiffness, hence weight transfer, hence grip.

Dann

anyone know if the stock bilsteins had the same 154/94 lb/in rate? I've heard they do but i would have thought they were stiffer.

NA8 Clubman Bilsteins had the OEM NA6/ NA8 springs which were 154/94 lbs/ in:
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