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Datsun 610 coilovers what spring rate?

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This is like asking how long is a piece of rope. There is no generally accepted rate as it is all pretty subjective. If I said 200 lb/in it may be a bone jarring ride that makes driving a chore. Younger owners tend to go stiffer suspension because they can handle it or accept it as being 'just right' because everyone else does. The car almost never gets driven at speeds where the suspension needs to be 'that stiff'. So why not run something that suits your driving style and comfort? Emphasis on comfort and enjoyment. I'm saying start low and work up. Also saying that I can't tell you what you will enjoy.


The stock 610 front coil spring rate is 96 lb/in. slightly stiffer than the original 510 at 89 lb/in. I find all stock spring rates very soft so that it is comfortable for all new buyers and for general driving transportation. Full out racing spring rates for the 510 are about 300 lb/in or 3 x the stock rate. Call that the upper limit. 'Probably' your range is likely between 175-225 lb/in. I have a 710 and the spring rate calculates to 100 lb/in stock. I trimmed the stock coils to get 150 lb/in and do not plan going higher mostly because I am no longer young, and I enjoy the ride plenty as it is. I go on week long trips, so ride enjoyment is as important as handling.


So... how to compare stiffness. You can measure a spring and set a value of 100 and another at 200 in lbs/in. but how does it 'feel'??? How do you measure feel? What is twice as stiff?? Well you can't really. All you can do is try it and like it or not. Adjust either way and try it again. Only YOU can know when it's right.


Try this.... "It's better to have springs that are softer and want stiffer than to have springs that are too stiff and want softer."


Some thoughts...

You will need to stiffen the rear coils a similar amount too. Because of control arm geometry the spring rate must be 3.8 times what you want. If you want a 200 lb/in rear spring you will need a 760 lb/in spring.

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Hello . Looking at coilover front struts what spring rates you guys using ?I have the L20B with A/C and 280zx disk brakes . I notice the 510 guys using 200lbs units .



If you get a chance go for a ride in 510s with a variety of different spring rates and compare. See what fits.

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Thanks for the reply. The main problem I am having is too much positive + camber up front . I have the 1969 510 front struts very short with S.T. lowering springs and no room in the spring tower for camber plates . My only option I see is going coilovers .with camber plates. The wheels I have are the xxR 521 series and are 16x8 with a 25mm back space so I made up spacers with long wheel studs . This is now compounding the + camber problem.

For now I am going to order the 200lb spring kit and convert over to 280zx front brakes . I need 1/2 inch to put the camber at 0 I also have adjustable lower arms to move the strut in or out .

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Wheel offset and width doesn't add or subtract camber or make better or worse. There is no angle change. But it can interfere with fender and strut clearance.


A smaller diameter coil spring will allow more camber adjustment. And so will adjustable LCA (lower control arms)

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Remember, shock dampening rate must match spring rates.

Too stiff of a spring on a stock dampener meant to control an under 100lb spring will make the car pogo-stick.

When you see some import 'tuner' car that's sitting low, bouncing down the street, this is why.


Years ago, when I first started upgrading the suspension on my Cressida beyond cut stock springs, I went to Tokico Illumina shocks, weld-on threaded bodies for adjustment, and tried 10k springs (kilogram/meter which multiplied by 56 gives you about lbs/inch) or about 560lbs spring rate.

The thing bounced pretty noticeably, even with the Illuminas set at their highest setting.

Had to go down to 7k springs on the front, and 4k on the rear (about twice the stock spring rate).

Not quite track type spring rates, but the bouncing was gone, and the car handled less like a grandma-mobile.

Wasn't that bad around town on ride quality, but 200+ mile trips became more of a pain in the ass, partly due to 'racing seats'.


Now I've gone more toward a track car, with real coil-over dampeners, all custom suspension arms, with heim joints, and all rubber removed from anywhere in the chassis. Spring rates are now 12k/8k (still soft for a 3200 lb car), and may go higher depending on what track I put it on.

And using it to bop around town is a pain in the ass.

But it is extremely stabile in a 120 mph sweeper, and rock solid handling at 160+ in a strait line.


Better to go soft to start, as springs are not that expensive to replace, neither are shocks, to dial it into what you want the car for.

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If you still have the original oil filled dampers you might look at just replacing the thin hydraulic oil with thicker oil. The compression/rebound ratios stay relative to each other but the effort increases (stiffens) I replaced mine with 20W BellRay motorcycle front fork oil. (comes in a variety of viscosities) This is how motorcycle owners 'tune' their bike rides. Cost me $17 CDN and a liter will do 3 strut refills.


After market inserts are generic or for some other vehicle and not an exact match for a 610 and though some say adjustable, how is this possible when installed in the strut??? Replacement after market struts are hundreds of dollars each. 

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Forgot all about the bike shock oil thing......

Getting old, and forgetting my roots :(


If you go to Z-car struts, there are a little more options for inserts.

Tokico used to make really stiff Z-car inserts, and they still pop up new in the box in Japan.

There were 3 grades under their 'Prodra-G' series, the blue, a slightly stiffer insert made for stock springs,

Then the Brown & Green. Brown was damn stiff, and the other was stupid, damn stiff meant for really strong springs.

Koni Reds were adjustable, and faily easy to find still, and Bilstein makes some too, that are good performance dampeners meant to use with stiffer springs.

Good thing about Bilstein, is that for a fee, they will re-calibrate their stuff for a small fee.

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Good information guys thanks.

I have some NOS Kontrolle shocks made by Tokico seem to have a very stiff rebound and down motion . the part number for these are for the 710 but these have a tootsie roll pin that can be cut off for shorter struts .

I have 35 years of old stock for the Datsuns  I may have some Koni's and I think these can be rebuilt too.

For now I will just build the struts and see what I have to use first.

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