Single leaf rear springs. (longish post)

[Daryl Smith]

Durable? Here's a 4x4 application....
http://www.bc4x4.com/inthenews/default.cfm?ID=138" onclick="window.open(this.href);return false;

From http://www.eatonsprings.com/monoleaf.htm" onclick="window.open(this.href);return false;
"Do not compare the current composite (fiberglass) mono-leaf spring being used by GM and others to a steel mono-leaf.
The composite mono-leaf spring is a completely different animal in its composition and it works. It is extremely rare for composite springs to suffer catastrophic failures."

http://en.wikipedia.org/wiki/User:Danie ... eaf_spring" onclick="window.open(this.href);return false;
According to Wikipedia, the Corvette has been using composite mono leaf springs since 1984......Smart car uses them now I think, possibly a Volvo or 2......

Considering the weight bias (I know near nothing about the 'handling' equation of a car), would not the fact that the spring simply works so much better make up for the difference in weight? Then move the battery to the parcel shelf area........First Aid kit and small tool kit in the trunk....Roll bar puts some more weight back near there......

Really tho, as attractive as the composite spring is, and I will wait for information on it, probably the Volvo springs would be the most cost effective.
Is that $75 each set or each spring? If we know what they weigh we can calculate approx. shipping costs........Anyone taking a trip to Europe soon?

Thanks for having a look Chris! We'll sort something out here soon. Hopefully the Ozzies and Kiwis don't scoop them all up before we decide......

[windy311]

Im going to use some carbon fibre snow skis as i think they will be ok.







Yes my tongue is firmly placed in my cheek.

[Daryl Smith]

Reply from Hyperco:
Daryl,
First off…thanks for the email and your interest in Hyperco products. I took a look at your links…..very cool! You guys certainly have a passion for these cars and they look absolutely great! As for composite leaf springs, unfortunately the manufacturing process for this product requires dedicated tooling / moulds…this makes it highly cost prohibitive on small runs (typical tooling and assembly fixture costs for a specific design is in the $12K to $15K range). We have had customers “adapt” existing designs to their applications. Naturally this works better in some cases than in others. I have included the information below showing the eye to eye, pin to eye etc. specs for the GM Camaro and Chrysler Motorsports leafs. My advice is that you contact a manufacture of steel leafs and give them the dimensions you require and have them produce replacements (it is relatively easy to roll flat steel in the arch / shape you require to produce replacement leafs). I would suggest you contact the folks at Landrum Spring….and speak with Jeff Fuller (800 424 0244) jfuller@mwspring.com.

Sorry I cannot be of more help, thanks for the opportunity and once again………….cool cars!

Sincerely,
Kelly Falls
General Manager

[Chris66]

Guys, i'm on to this, sorry for not spotting this topic, i called a car junk yard today, price is $75 a piece + shipping, maybe there is other places with better prices, that is one thing i have to look in to.

Let me know what's next.

Chris

Bump to this.
Guys, so much discussion on this topic, now i chime in and offer to help, call and get a price and the thread dies, i really don't get it .

Chris

[Linda]

Chris,
More stuff gets talked about than ever gets done. So plan accordingly.

Linda

[SLOroadster]

Guys, i'm on to this, sorry for not spotting this topic, i called a car junk yard today, price is $75 a piece + shipping, maybe there is other places with better prices, that is one thing i have to look in to.

Let me know what's next.

Chris

Bump to this.
Guys, so much discussion on this topic, now i chime in and offer to help, call and get a price and the thread dies, i really don't get it .

Chris

I did ask what approximate shipping for a set would be.

Will

[Chris66]

Will, you did so, to find the shipping price i will need to know of the size and weight, then it will be a piece of cake to find a quote, however i do think that the far cheapest way is to ship 5 set as sea freight, give me the measurements and weight of a stock spring and i will find a quote.

Chris

[Daryl Smith]

Shipping weight? From first post ".....Weighing about half of a standard rear leaf,......"

Chris,
Sorry if we've put you out. Information is an odd thing. What seems like a great idea and works well for some, doesn't for others. And I found out I had options! Although I am very interested in the mono leaf suspension, it has some drawbacks in the safety aspect of the steel leaf, as well as putting it to use. A lot of what I've read over the last 3 weeks has me wondering.
Being as the Volvo 360 are very stiff springs it would require an upgrade to the front springs, and shock modifications as well.....basically a complete revamp of the suspension system.
I would prefer to do just the leaves if I could....

“…the factory valving that Koni set for the Datsun roadsters seems to be much stiffer in the rears than in the fronts - which sets up that oversteer problem, and doesn’t control the heavier front end very well. So the valving was swapped, front to rear, essentially.”

How is this accomplished??

“some 360's had a higher spring rate than others. The one to get, ideally, is this one, with the spring eye "in line" with the centre line of the spring.”

“I believe that my springs came from a 360, around '86 or '87. You can pick the right ones by the loop at the end. Have a look at the pictures of mine to check it out. At the rear eye, it should "lift" and loop, so that the spring eye is in line with the centre line of the spring.”

“….we fitted 15mm, 780lb springs to the front – about 50% stiffer than standard.”

A good discussion on the composite springs: http://forums.caranddriver.com/showthre ... 750&page=8" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;

I really like a lot of what I've read on the composite springs and am considering that option, but there are cautions there as well. Heat and some chemicals can cause delamination of the spring, physical damage may shorten it's lifespan, and it is quite expensive in comparison. There is a roadster owner here with a set on that I will look at tomorrow morning at Ross's shop and will take some pictures. He put me onto this site yesterday:
http://www.flex-a-form.com/" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;

So again, Sorry if we put you out, and I thank you for looking into it for us, but I think IF I were to go with a mono leaf spring, I will likely go with a composite and a tad lighter spring rate than the Volvo's (125 -150 lb/in maybe?).

[Chris66]

Daryl, you did not put me out, there is also other members that have shown interest in this, it doesen't help me anything knowing it is half the weight of the stock spring and you are not getting me to go out and pull off a spring just to put it on a weight , sure there must be some here with a spare stock spring.

Even if the avalability is big over here, it is not for me to do the upgrade, it is just that there is so many members here ready to help me out, so i'm glad if there is anything i can do in return.

Chris

[Daryl Smith]

Funny, I just borrowed a leaf spring from Ross this morning for measurements and never thought to weigh it....

My bathroom scale says...22lbs for a brand new, early 4 leaf spring. Part #55020-10500

I was skeptical 'cause it felt heavier than that, but the scale says 25 lbs of dumbells weighs 25 lbs so..........

It also says this particular dumbell wieghs 172 lbs and 27% body fat.......... I don't trust it!

[dbrick]

Never mind, dead link

[Chris66]

I tried to make a online quote on "post danmark" our USPS, based on 40 pounds, witch is the biggest parcel they have online, it is $200 in shipping as economy, so unless it have to be shipped to me first it will have a total of $350 for two springs shipped, it's not the first time i have experinced shipping to be higher than parts.

Chris

[Daryl Smith]

Chris,
Thanks for checking. That kind of shipping cost is unbelievable!

Does anyone have the bolt diameter for the bolt which goes through the eyes of the leaf springs? Front bolt and rear shackle? I really don't want to take mine apart to check it.

Can anyone also confirm the stock spring rates @ ~700 lb/in front and ~150 lb/in back? (found by searching forums)

This site lists the front at 522.5 lb/in, but doesn't seem to list a rating for the rear....
http://dsoanews.tripod.com/specs_66_1600.htm#suspension" onclick="window.open(this.href);return false;

Thanks

[DJ-01447]

G'day all.

Further to Volvo rear spring saga, when you finally get hold of a set, they still need to be modified before fitting them to your Roadster. The spring requires the following mod's to be carried out:
1. Cut the spring(front half only) to the correct length,
2. The cut end then needs to be re-rolled into the correct eye shape, and finally
3. The spring has to be re-tempered.

All of this should be carried out by a competent spring shop/works.

Then they can be fitted to your Datto!

Dave

[st3ph3nm]

Hi guys,

Sorry, I've been offline for a bit. First of all, a head's up to Ebay:

http://tinyurl.com/l2c5d4" onclick="window.open(this.href);return false;

It's a set already pre-made.

As to the safety of the springs, I can't imagine Volvo, of all companies, having *any* component in their vehicles that wasn't thourougly tested for safety. One of the reasons we can't get hold of these springs easily is that they don't fail, (nor do the cars) so they aren't available as an off the shelf spare part.

As for the shock absorber settings, the Koni shock absorbers are designed to be re-valved. Any Koni distributor should be able to do this for you - I was quoted $100 per shock when I got mine done. The key is to communicate with them that you *don't* want the original settings kept. I can't remember the actual terminology used, but you need to essentially swap the settings front to rear. BTW, this is a good thing to do on an otherwise stock roadster. Changing those shock settings around will improve ride, handling and turn in - without going to the trouble of changing springs. And yes, if you *do* go down the path of the Volvo springs, as I mentioned in the original article, you will need to change the front springs - otherwise the rear end will be way too stiff, and the car will become quite tail happy, and really dive under brakes.

Cheers and good luck,

Steve