Datsun Roadster Forum-311s.org

Daryl Smith wrote:I have only seen the 150 lb/in rating. Don't know which spring it applied to.

Would be nice to be able to document:
Stock Early Leaf: ?
Stock Late Leaf: ?
Competition Leaf: ?

I also see people saying that you want the front suspension stiff and the rear suspension soft, but then that the early stiff springs were better than the late softer springs??? I'm assuming the comp leaf was stiffer than the early leaf?? Does the stiff front suspension and soft rear suspension have more to do with the shock valving than the spring rate?

I was looking for info on the MG springs, but couldn't find any. Somebody have an MG to take some measurements off of?

Daryl, all things are relative. The Volvo springs are quite a bit stiffer than the standard leafs, and probably a similar rate to the competition springs (though they may be slightly softer). The trick is that the mono leaf is much more compliant and moves more freely than a leaf pack - a combination of the reduced weight & no friction of leafs in the pack moving against each other. They've been tried with a standard front end setup, but were found to be too stiff - the car turned into a tail happy oversteer monster. See my first post for the ideal setup. It's true that retuning shock settings and upgrading front suspension will give you some of the benefits of our experiments, but those mono leafs are just indescribably good!

Cheers,
Steve

Very cool! Now get busy boxing up your old springs and send them to me...

From what I can tell, the Volvo springs are in the 185-190# range. I'm about 190#s, and when I step on the center of the spring, it deflects about 1 inch. Yes, very rudimentary, but its close. The ride is revolutionary, likely in the way Alvin found with going to the 4 link. These are a very worthy upgrade for anyone. The one caveat is that KYBs likely won't be able to handle the spring rate (can't say for sure since I don't have any.)

Will

The following is a 'cut and paste' of the questions and answers to and from Flex-A-Form regarding the group buy of their composite fiberglass leaf springs.
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Thanks Mark,
A few more questions have popped up, Your answers will be forwarded to the group/forum:

>1. Can we also order different ride heights? I have read in a forum where the eye bushing/clamp at the end of the spring may be 'flipped' to lower the ride hieght?
1. Yes, what is described on the forum is reversing the eyes, which reduces the ride height. There is a plastic insulator pad in the center that is available in increased thickness when additional lowering is specified.

>2. Is it acceptable to use lowering blocks with these springs? Maximum block thickness? Extra stress on the springs with lowering blocks?
2. Yes, lowering blocks are frequently used with our springs. We've never seen a problem, although extremely thick blocks can get to be a concern. I can't see any reason on this application why there would be problems with any block.

>3. Are we able to spec the spring bushing material and hardness?

3. Our standard polyurethane bushings work well in 95+% of the the applications we do. We have Delrin bushings available as an added cost option. We have also occassionally provided purchased poly bushings or aluminum bushings.

>4. For the weight of the car, might you recommend a slightly softer rate? 135 lb/in maybe? (rate used/recommended in MG's with composites). Higher than 150 lb/in for racers?
4. The main thing to remember about rate is that the subjective "feel" of composite monoleafs is quite different from that of steel multi-leafs. A general rule-of-thumb is that our springs feel like a steel multi-leaf that is about 20% lighter. We can provide 135 lbs. or any other rate specified, but that is a very light rate for a composite monoleaf. The road racers that are performing the best with our springs have, in most cases, gone heavier than they originally thought would work. For example, one of our MGA customers has gone to 265 lbs. and several others use 225s. I'm almost certain your racers would end up going substantially heavier than 150.

>5.Scott's composite springs were only 2" wide. He had to adapt somehow (haven't got an answer from him yet). Would you include/recommend the fix for this if the springs supplied to us are not 2 3/8" wide?
The chances for a higher volume of sales goes up if we have a completely bolt in product.

5. If you specify 2-3/8, that's what they'll be. Scott's springs were made before the ownership change when there was virtually no quality control. (Sorry Scotty......)

>6. I have had one inquiry about the Flex-Track torque arrestor system cost, and possibility of use on our cars?
6. We've never made a Flex-Track for this size car, so we would be developing it for the application. It certainly can be done. Price would be about $375 per pair with exact price depending on how much work is required to fabricate the center plate that the U-bolts go through.

>7. I'd like to streamline the ordering process if possible for this group. The spring is the same for all Datsun 1500, 1600, and 2000 Roadsters from about 1963 - 1970.

>If it works for the group buy, could we order with the following:
>Model: Datsun Roadster '63 - '70
>Ride hieght: Stock to maybe -2" ?
>Spring Rate: 135 - ? lb/in.
7. The data you listed is fine for orders as long as we can get confirmation on a few dimensions before we start the first ones just to make sure we're on the same page.

>8. If some of the group wanted higher or lower rated springs (ie: 130 lbs/in, 150 lbs/in, 170 lbs/in) would this also qualify in the quantity buy or would that be a separate quantity?
8. Any rate will apply to the quantities for discounting.

>9. Questions regarding the Warranty......

>I read all this info that the composite is 'stronger/more durable than steel', 'good for over 200,000 cycles vs steel at ~50,000 cycles', 'no sagging', 'corrosion resistant', 'incredible service life'.............(okay, not your site.....but still composites.....)

>With all this on different sites on the internet, WHY is there only a ONE year warranty? Seems very short, especially since most of these cars will only be used a short period each year, or low milage anyway.....I understand that there are certain situations which are more detrimental to composite springs than steel, but a properly installed spring, it seems, should have a longer warranty considering the proposed benefits/strengths......? I'm afraid I don't quite understand, unless there are recurrent problems which I have not seen yet........??

>An explanation would be appreciated. Hard for me to explain to others when I don't understand why........
9. The best answer to your warranty question has to do with the automotive aftermarket. A one year warranty is common for aftermarket parts, which these are, because they frequently are subjected to demanding, even harsh use that pushes them to, and beyond, their design limitations. Thus, a longer warranty would subject us to a lot of claims by people who acquired a part but were not the purchaser and/or who don't remember the warranty conditions.

These should not be represented as being "stronger than steel." That claim is too general at best, and probably more accurately is just plain wrong. Failures of composite springs that are not being used in a correct application are not uncommon. That being said, in practice we almost always stand behind our springs beyond the official 1-yr warranty period when we are familiar with the owner and the application and when we can examine the problem first hand.

Hope this helps in the explanation of the warranty.

Thanks for the inquiry.

Mark
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I haven't been following this 311s topic but just checked it out briefly. Since it's 8 pages long now, I haven't read thru it all yet.

However, my 1998 NISMO catalog indicates the rear comp springs are rated at 207lb/in. Front comps are 862 lb/in.

For my autocross purposes, it seemed the rear comp springs were too stiff, so I removed the short leaves from the springs. It softened it up enough to make it handle more neutrally. I also removed the NISMO rear sway bar and added a panhard rod. But after removing the short leaves from the rear comp springs, the rear end bottoms out on the bump stops on severe road bumps on the street and it hurts.

Since haven't bought a NISMO catalog in several years, today I googled NISMO catalog and they have it online now. I found that the online catalog does not have anything for our roadsters. But it was amusing that they comp parts for a 240ZX. I haven't seen a 240ZX yet. Has anyone else?

I'll post this on the 311s forum too.
Gary Boone
1970 SRL311 with EFI'd U20, running better all the time, but more tuning ahead.
http://www.picturetrail.com/sfx/album/view/271132" onclick="window.open(this.href);return false;

I'm looking to spend 2 days autoXing this weekend. I might even do a track day before I pull the springs. I want to be sure they are the ticket before I go and try to reproduce them. I will say this again, for the street they are awesome. They feel even better with a full tank of gas. On my way home from work this afternoon, I really stuffed it into a corner and for the first time ever, it felt like there was a hint of understeer. The car feels settled, and poised. I'm going to run with the PCA on Sat, and then head down to Marina for the NORCAL UFO event (since I have the season championship wrapped up in Vintage Stock class, I might as well run the roadster and get some more testing in.) I might go as far as to bring my 21mm swaybar out to the PCA event if I have an understeer issue in the morning. I'm also going to have in car video going so the ride should be pretty easy to tell.

Will

st3ph3nm wrote:

SLOroadster wrote:HOLY COMPLIANT RIDE Batman! These things are unreal. Ride quality is very good. I'm talking better than a Miata, in the realm of a BMW 3 series. I can put power down and go in the direction I want to, even on rough pavement with 3 year old, bald, hard Falkens. I can't wait to run the car this weekend.

No doubt about it, this is the way to go. It did raise my ride height in the back a substantial amount, but the car feels really good, even on semi rough roads. Seriously, the springs are no joke.

I'll post some pics soon.

Will

Told ya!

After watching your escapades on the youtube footage, I knew that this would solve your woes. I'm glad it worked out well for you. Congrats. It's hard to describe the improvement, isn't it. Railway tracks are no longer a fearfull hazard!

Cheers,
Steve

Railroad tracks become a "what railroad track?" Or "Uneven pavement? Oh, uh yeah that was uneven" (specifically 101 north and South in Santa Rosa. There is about a 2" difference in road height between the fast lanes and the slow lanes right now.)

So, autoX #1 is done for the weekend, now for the 2.5 hour drive south for #2 tomorrow. I can say this, these springs work wonders. No I didn't get TTOD, nor was I really even close, but I was more consistent than a quartz crystal. in 8 runs, (well, 7, had a minor issue on run 6) I managed to only vary my times to +/- 0.2 seconds from my first run (that I did without a walk through.) with cold tires. I played with tire pressures, and nothing really made any difference. You will be able to notice how much better the car rides just in the video quality. It will be a night and day difference when I post the old video shot on the same course (different layout, but the tough parts both run the same way.) and todays runs. I'm also planning on shooting some at Marina tomorrow. (good pavement, and different style course.) I truly don't really know where I could pick up 5 seconds on my runs. Its got to be there someplace, but I don't know where.

I'll post more findings and a brief write up tomorrow. I'll also do a race report in the racing area. I do have video, and there will be lots of pics from tomorrow.

Will

Will, I look forward to your progress report, and video. This is cool!

Kyle

Results from yesterdays race. I finished 2nd in class, but I did another 5 runs that didn't count and beat the winning class time with a passenger in the car by about a second. The word is the car corners much more flat, and will drift in an easily controlled manor. My fastest time of the day I was actually drifting the corners, making all the drift guys look slow (15 seconds slower or so). A better write up of the weekend to follow this afternoon/evening. It will be in the racing part of the forum.

Will

Will, I am interested in where this is going. After about 150 miles of road testing, trying to get all the little things adjusted after a total teardown, I'm thinking I may dump my Nissan Comp leafs. The ride is harsh to say the least. I took my Wife for a ride on Saturday. No seat belts yet, hit a big bump going about 50. I thought I was going to launch her right out of the car.

So, what is the difference between your springs and Daryl's? Are yours the composite ones, or are Daryl's? What is the weight of your springs? Was yours a custom build? I'm looking forward to your race report.

Kyle

Will,
Great that the springs are working for you. I'll look up the racing post as well!

Just to update those interested in the composite spring, I am going to order my set tomorrow, and when it gets here and installed we will have a reference for everyone else to order from as far as ride height and rating.

I have sent a couple more questions in and will post the answers when I recieve them, as well as a clarification on the 'feel' vs rating.

http://cgi.ebay.com/Datsun-Roadster-Sus ... 286.c0.m14" onclick="window.open(this.href);return false;

anybody see this, kinda expensine though

Kyle, what shocks do you have? I went to the GR2's and it made a world of difference.

fixitman04 wrote:http://cgi.ebay.com/Datsun-Roadster-Sus ... 286.c0.m14" onclick="window.open(this.href);return false;

The whole setup, wow!
So is this the same "aus" seller of the earlier posted springs?
WTF is going on here?
Who is making what?
Where is it coming from?

The guy who built Phil Brook's car is the one making the springs, and modifying the Bilstein shocks. A friend of his is selling the stuff. His name has been mentioned several times in this post. I'd say the whole 9 yards is worth the $$$$, too bad the shipping is going to cost about $500 or so.

Will