As revealed earlier, I don't know about suspension. I did know enough to listen to the pros and have taken Eric's set up advice. (guess who has new Bilsteins coming ) My question is this; how do I identify what I currently have? Is this done by the number of coils? Is it stamped somewhere? Color coded? Here is a shot of mine. And...what does 100,120,140lb represent? What happens at a given value? TIA, kent

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If my math is right, I think all the stock springs listed below are around 150 pounds. AFAIK, the three variations are about 14 pounds between the lowest rate mentioned and the highest.

EDIT: I am wrong.

I think your math is wrong, McMark. Specifically, not accounting for the "P at L1 = 239mm". I believe they're talking about a pressure at a given spring length, though it is possible it could be a given amount of reduction in length.

The oldest info we have is that the stock springs are on the order of 60 lbs.


The way we rate springs in the US is in "pounds per inch". That means pounds of force that it takes to compress the spring one inch. Most springs are relatively linear in rate through most of their range, meaning that compressing the spring two inches takes twice as many pounds as compressing it one inch.

Some are "progressive rate" springs, where compressing the spring two inches takes more than twice as much force.

--DD

Hey guys, thx for the quick response but I guess you went over my head because I still don't know what I've got or what was said. I did find this but doesn't mention the 914. http://forums.rennlist.com/rennforums/924-...color-code.html Maybe someone could tell me who sells 140# replacement springs or how to test existing springs to determine which I have.

I'm wondering too about this. Since mine has non-stock shocks, I'm guessing the PO also replaced the springs. I'd like to be able to figure out what I've got.

The rate is "pounds of force per inch of deflection". That suggests how you would test it:

Weights to put on the end of the spring, and a ruler to measure how far it compresses. Take measurements with different amounts of weight.

lbs of weight / inches of compression == lb/in spring rate.

...Or you take them to a shop that has a spring tester, which does the same sort of thing with much more precision.

--DD

Yup. I was wrong. Found a spring rate calculator that takes into account wire size, number of coils, etc. And came up around 80 pounds. Of course, that's just rough numbers and for new springs. I don't have any idea of the rate of decay on spring rates. But between 60-80 pounds for stock springs may be about right.

Measure spring length at rest. Put a known weight on top of the spring. Measure difference in length.

Plug the known weight (in lbs) and the difference in length (in inch) into the formula above, normalize to 1 inch and voila!

If those are KYB's it wont matter..

Spring ID for the simple minded.

Remove springs, toss them.
Order springs you want, install them.
Now you know what you have installed.

Rich

As I recall, 100 pound works well for 914-4 for street driving and once-in-awhile autocross or WCC track day. Any reason to go higher for such use?

I plan on doing just that after I drop the trailing arms. Then I'd like to follow up with a spring test by a pro to verify what I think I already know.


They are and your right. Erc is sending me some Bilsteins.


I agree. I want 140# springs. Now tell me where to buy them.

All over. Performance Products, GPR, Pelican, AA.... Most of your favorite places (did I mention Pelican Parts?) will carry them if they carry 914 stuff at all.

--DD

Pelican lists them as NLA as did GPR but I didn't know about Performance Products. They have them for $90 ea., Thanks Dave

I bought 165 lb. progressive springs From Troutman in Temecula. They were at 27831 Sycamore Mesa Road. 909 699 9277. That was about 10 years ago and I'm not sure they are in business anymore. I also got cross drilled rotors from them. Too bad if they're no longer around.
Cheers, Elliot

my Eibach 140's came from Pelican via Rebel Racing but they are for the coil over kit and the diam. is different from stock, call Glenn Sager X240

Troutman moved to the East Coast. House has a caretaker & lots of Porsche parts but they have been gone though.

Springs / brake hoses are no longer being made.

Dont mean to hijack but could someone comment on the meaning of the various color paint dabs used on the OE springs ?
I know that I've read that yellow was for 914 6 specific springs. True ? if so what does red or green indicate ?

If you can't find your 140 lb springs, I have a pair that I bought a couple of years ago that I do not need.

Well Hell, PM me a price. That would be a win/win deal.

Yea, me too. I found a post on Rennlist re: color code on some 911's but those started at 160#, IIRC. Nothing on the 914. I'll find out soon enough when I yank mine off and get a better look at them. Right now I can't tell what is painted over and what might be identifying dots.

If you buy these, I can pick them up for you on the way to the G&R. Unless ww914 is going also.

OK, I'm not done with this subject, yet. Just got side tracked. I removed my factory springs (100lb) and they do indeed have 3 green dots. They didn't appear to be dots when viewed from below but as this pic reveals they are identifying marks.

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and a shot of the new 140lb Weltmeister's sans colour coding.

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I'll do the squash test (as described by DD) to both old and new springs before I button this up. I want to see how well the old springs have held up for 35 + years. More on this, later.

Right behind you on this one...my car has KYB's too, which causes everyone who sees them to make the "stink face" (see scotty b's avatar). I don't know any better after 11 years. Bilsteins, Boge's and Koni adjustables are on my short list. Did you consider either of those when you picked the Bils?

Hey Chris, I'm trying to keep busy until a donor car lands in my lap. I didn't check out Koni's or Boges because I have Bilsteins on Whitey and love them. That and I always try to buy from a member vendor. For me, the most important part of any transaction is service "after" the sale. ps Did you see JC's score. I look every day for a donor and he has one land in his lap. Go figure.

Very good point. I'll check in with Eric once I get the engine/trans sorted....working on the clutch setup now.

Yeah that EZ30 score was huge! $400 for all that? The newer the better it seems like. Had to replace a lot of brittle hoses, a few sensors, etc. on mine due to the harsh weather around here. Lots of snapped bolts too. Which were fun to drill out.

Troll Craigslist...that's where I found mine. Lots of Subies with bad transes out there because its the weak point.

Me Too, Getting ready to do rear springs. I have a set that has a yellow dot and was supposed to be OEM. Someone suggested these were off a 914-6? Is there any reason not to use them on my 914-4? They look like new stock.

Doug

the progressives will have a softer rate for the first amount of compression and then the final will be 140lb.

the tighter spaced coils will compress with the lighter weight and then the coils will stack and the rest of the spring will compress.

I want to see your clutch work. I'll go with a 33 in a heartbeat if one appears. 7 main bearings, 9000 crazy RPM's and best of all....wait for it........an existing Mega Squirt map for it. Seriously, I'd be washing & waxing Bigkats car for that kind of info.


As you can see, I'm certainly no expert in this field but I would if your doing shocks. They're only $99 new. In my case, I had no choice as I'm adding weight so I needed a new suspension.



Thx for taking the time to explain that. I love info.

There, I fixed the quotes for you.

Thx Rich, I ventured into an area unbeknownst to me. Guess what? Another spring question. The new or progressive springs are shorter than stock. Should the shocks have some pre-load just to keep them tight when the wheel drops or the car is jacked up. I needed to adjust the perch 2 rungs above the lowest setting just to snug them up. What is the correct method? TIA once again, kent

Most of the aftermarket springs have a shorter free length than the space for them at full droop. I zip-tied the springs to the upper perches to keep them pointed the right way. And when I jack the car up, I check the spring position as I let it down to make sure the springs sit on the perches.

--DD

Ah hah! Mystery solved. The ass end is so high it looks like an Alley Cat in heat. I'll lower it and use your method. Thx, Dave.

Anyone know what spring strength 3 red dots signifies?

924S and 944 up to end of MY 86 with M030 - 1 to 3 red dots

Sweet pea was wearing 944
Shocks?
I’ll wondering what stiffness the 3 dots signify.