I'm in the process of getting all the parts needed to convert my stock struts to coil overs.

The only problem, what kind of spring rate do I need?
The vehicle in question is a Datsun Ute with a A14 in.
Will be used for gymkhana racing.

Some clever okes reckon 500lbs others say 200-250lbs.

Does anyone know the rate on the standard springs on a ute, because that is way to soft.

Standard front springs are 90 lbs/inch
Typical recommendations be:
* Serious street racer: 175 lb
* Dedicated track racer: 250 lb

The 500 lb/in is probably people thinking about new VW Golf, a much heavier vehicle, and other similar overweight "small cars"

On my street/autocross 1200 I'm running 250# springs in the front. They seem to match up with the rear leaf springs nicely. If you stiffen the front with higher rate springs and/or stiffer anti-sway bar you will need to add a rear anti-sway bar, preferably an adjustable one so you can balance the handling of the car.

I use 250pd x (200mm freelength) on my 1200 with a ca18. I'm very happy.

250pd with standard length springs would be good for a v8

As you are going coilovers, you will probably run shorter springs so you can fit wider rubber.
When you run shorter springs, you need much larger rate springs to stop the same weight in the same distance.

Keep all this in mind.

I currently run a kings spring 275 lbs 180mm free length spring in my track car and a 5kg/mm generic [280 lb] 180mm free length in my streeter with a tender spring. I would say that its [streeter with 280lbs] just a tad too firm for the street. 4kg /mm [220 lb] would be better

The coil overs in my streeter have a much longer amount of travel when compared to the coliovers in the track car.
I would suggest it is better that the wheel drops into the undulations in the road surface rather than skipping over the top of them on the street. If the tyre is not on the road there is no grip.

500lbs springs in a 1200 would be just plain silly

See that's something I want to sort out now that I have a little more time. What strut\shock combo is used in both instances? I was planning on using 200lbs\in springs with my stanza struts but I don't know how short I should cut them. I had some basic shock options form -1 inch to -4 inches but these are all non adjustable gas inserts for heavy cars (1200kg roughly)

Hey Benny - your kings springs with 275lb rate - are they just std off the shelf 'sports low' - KDFL-57 ?? Or are they a spring originally for a different car that fit the bill, or are they just something not listed in the std catalogue?

In my case the 250# springs are mated up to shortened B310 struts and KYB GR2 gas strut inserts for the Z-cars. IIRC, the struts had to be shortened ~2" to mate up with the Zed strut cartridges. The valving on the Zed strut carts seems to work well with the 250# springs.

Gary

My streeter struts are based on the B110 /S13 brake conversion with KYB golf /rabbit inserts and the track car struts are based on Stanza struts shortened with koni sport adjustables.

JMAC, the 275lbs kings are from the prosport catalogue:

Part # KPS-104-X5K
F-H 180
ID 65
lbs 275
S-H 59

F H = free height
S H = solid height