Author Topic: What Were 14" Front Springs Originally On?  (Read 817 times)

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Offline thehackmechanic

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What Were 14" Front Springs Originally On?
« on: Friday,December 06, 2019, 05:51:38 PM »
I'm doing a budget front end refresh on my '74 TCS. My presumably original front shocks work (the car sat for 40 years), but they feel awfully soft. A few weeks ago, there was an old set of Spax adjustable shocks and springs (non-adjustable perches) for a Europa on eBay. I took a risk for $225 shipped and bought them. The guy selling them didn't know much about them; they apparently were with some stuff in a storage unit. There is a 14-day return on them, so I thought I'd pull them apart to make sure the shocks worked (e.g., that they weren't blown or seized and the adjusters worked). At first I thought I'd just install them and bounce the car to check, but that seemed like more work (the front end of the car is currently completely apart) than simply pulling the springs off the Spaxs and exercising the shocks by hand.

This led me down the rabbit hole of finding/making a spring compressor that'd work on these itty bitty springs, as none of the three compressors that I owned fit. I cobbled something together with S-hooks and turnbuckles, and finally managed to pull the front strut assemblies apart tonight.

Both front shocks appear to work--they're neither blown nor seized, and the adjusters increase and decrease damping--but I'm, uh, shocked at the front springs. They're 14" long uncompressed.

I pulled apart one of my presumably-original front shocks. Its spring is 12" uncompressed. Both it and the fron springs on the Spaxs were the same 9.25" length compressed.

I can't find any reference online to a Europa spring this long. I suppose the adjustable Spax shocks (if the rears are good too) are still a good enough deal to keep, and I suppose that I can put my original 12" spring on the front. But, if anything, I was hoping to get the nose a little lower as part of this procedure. I know that it's the compressed length, not the uncompressed length, that dictates space above the tire, but I can't imagine that this 14" spring is going to settle MORE under load than the 12" ones.

Any intel as to what these 14" front springs were from?

Thanks.

--Rob Siegel


« Last Edit: Friday,December 06, 2019, 06:06:41 PM by thehackmechanic »
'74 TCS, 24k miles, up and running after 40 years
'72 BMW 2002tii
'72 BMW Bavaria
'73 BMW 3.0CSi
'79 BMW Euro 635CSi
'99 BMW Z3M Coupe
'99 BMW Z3
'96 Winnebago Rialta

Five books available on Amazon (www.amazon.com/s/ref=nb_sb_noss_1?url=search-alias%3Daps&field-keywords=rob+siegel)

Offline Certified Lotus

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Re: What Were 14" Front Springs Originally On?
« Reply #1 on: Friday,December 06, 2019, 08:39:59 PM »
I never measured my OEM springs when I took them off my 72 TC. I wouldn’t be surprised if they were 14”. I installed 8” springs on my new AVO shocks which were too short for road use. Then I changed to 10” springs which are a perfect stance and great handling.
The first photo is the OEM springs and shocks. Second is 8” springs on AVO adjustable shocks. Third photo is 10” springs on AVO shocks.
« Last Edit: Saturday,December 07, 2019, 02:15:04 AM by Certified Lotus »

Offline cwtech

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Re: What Were 14" Front Springs Originally On?
« Reply #2 on: Friday,December 06, 2019, 09:29:07 PM »
I don't know the origin of the 14" springs, so no help here.

The TC Manual lists the front springs as:  13.5 coils of .40" wire diameter, free length of 12.51", fitted length of 7.88", and rate of 116 #/inch.

Offline 1970EuropaGuy

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Re: What Were 14" Front Springs Originally On?
« Reply #3 on: Friday,December 06, 2019, 09:49:46 PM »
Those look very similar to the old shocks on my S2. The springs were close to 14 inches, raising the car to a legal height in the US. My cheap solution was to cut them down to 11 1/2 inches. made a huge difference in front ride height while giving me a better feel on the front end. I will likely cut them down again to about 10 inches. It seems 1 inch cut will lower the car about 1/2 inch.
« Last Edit: Friday,December 06, 2019, 09:56:01 PM by 1970EuropaGuy »

Offline thehackmechanic

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Re: What Were 14" Front Springs Originally On?
« Reply #4 on: Saturday,December 07, 2019, 06:30:10 AM »
The other thing is that, counting coils, the original springs I pulled off the car have 13 coils, and the ones that came on the Spaxs have 14. This seems to imply that, given both the length and the number of coils, they're from an S2, which is certainly possible.

http://www.lotus-europa.com/data/xr1/r89.html

S2 after September, 1971
No. of Coils       14.75
Wire diameter      10.16mm (0.400")
Length, free      34.90cm (13.75")
Length, fitted      ?.??"
Rate         ??? lbs/in
Load, fitted      ??? lbs
'74 TCS, 24k miles, up and running after 40 years
'72 BMW 2002tii
'72 BMW Bavaria
'73 BMW 3.0CSi
'79 BMW Euro 635CSi
'99 BMW Z3M Coupe
'99 BMW Z3
'96 Winnebago Rialta

Five books available on Amazon (www.amazon.com/s/ref=nb_sb_noss_1?url=search-alias%3Daps&field-keywords=rob+siegel)