Spring rates
Spring rates
Author
Discussion

hoofa

Original Poster:

3,153 posts

229 months

Saturday 19th December 2020
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Question for those of you on aftermarket shocks what spring rates are you using ? Also what are standard rates ?

QBee

22,014 posts

165 months

Saturday 19th December 2020
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What you need varies from damper to damper, I would have thought. And the use you are making of the car.
I have had 500 lb front and 400 lb rears for track days with Gaz Gold Pros, but when I changed to Racing Reds they were better with softer springs.
Mat races with somewhere between 700 lb and 900 lb springs IIRC, but race tracks are smooth and he wants the car to corner flat.

rigga

8,791 posts

222 months

Saturday 19th December 2020
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Road use protech have 400lb front and 325lb rear springs

Zener

19,284 posts

242 months

Saturday 19th December 2020
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Standard are Fr 325 and Rr 275 IIRC I got 450 Fr and 375 Rr on Gaz Monos hard but not overly but then I'm still on 16" wheels , I have recently driven a factory stock BMW Z4 M sport suspension option on run flats that was bone shakingly hard frown so I have a good compromise & compared to stock suspension night and day handling wise even compared to new old stock Billies and new springs , not referring to the later Ben Lang spec Billies however , I think a standard car is under-sprung TBH 2nd comes damping







Edited by Zener on Saturday 19th December 13:43

J-2

35 posts

82 months

Saturday 19th December 2020
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I had Protech's with 400 front and 325 rears and was not satisfied with them I always found them to soft and the car would bottom out. The shock's did not last very long before they started to leak so I went back to Bilstein's as my car is only used on the road.

MisterT

326 posts

247 months

Saturday 19th December 2020
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From a thread I posted in back in 2013

MisterT said:
I spoke to the man at Eibach a couple of years ago when I was trying to sort my Griff spring rates.

I quoted him my original TVR spring part numbers and this is what he came back with;

Front C0098 48.6 N/mm x 5.709 = 277.5 lbs/in

Rear D0103 38 - 60 N/mm (progressive rate spring) x 5.709 = 217 to 342.5 lbs/in

The conversion factor he told me to use was 5.709 x the rate in N/mm

hoofa

Original Poster:

3,153 posts

229 months

Saturday 19th December 2020
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Well gone for 400 front 350 rear so will see how it goes

Classic Chim

12,424 posts

170 months

Sunday 20th December 2020
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MisterT said:
From a thread I posted in back in 2013

MisterT said:
I spoke to the man at Eibach a couple of years ago when I was trying to sort my Griff spring rates.

I quoted him my original TVR spring part numbers and this is what he came back with;

Front C0098 48.6 N/mm x 5.709 = 277.5 lbs/in

Rear D0103 38 - 60 N/mm (progressive rate spring) x 5.709 = 217 to 342.5 lbs/in

The conversion factor he told me to use was 5.709 x the rate in N/mm
This is very confusing /interesting considering everyone’s been going the other way for years.

This using 15/16 wheels on old style ( harder ) tyres if these are shocks off an original factory car, that’s thrown a spanner in the works!
I think the thinking must have been mild understeer is better than wild oversteer by having the front softer as it’s easier for a none pro driver to deal with and more predicable. Passing brake tests etc etc.
Really weird as I thought it was something like 325 F and 275r as standard or even slightly harder on early Griffs .
Where are all the old factory boys when you need them : D

glow worm

6,887 posts

248 months

Sunday 20th December 2020
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Classic Chim said:
Where are all the old factory boys when you need them : D
He's on e-bay blackdownauto
https://www.ebay.co.uk/itm/TVR-Griffith-Chimaera-E...
smile

J-2

35 posts

82 months

Sunday 20th December 2020
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It was Paul and Heath at X Works that recommended that I went back to Billsteins and they got them from Ben Lang and fitted them. Made my car a lot nicer to drive.

Classic Chim

12,424 posts

170 months

Sunday 20th December 2020
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glow worm said:
thumbup
They are variable rate too, I never noticed that before. Billies from Ben are on my to do list yes