Hi, as follows:
wire diameter (WD) 11.5mm
total number of turns (T)(including the flat ground top and bottom coils with the zero pitch gap) 8.2
outside diameter (OD) 97mm
spring rate (SR) 250 lbs/in
free height (FH) not sure
heavy duty rear:
SR 428 lbs/in
FH 205mm (sits about 1.5 - 2 inches lower than stock)
stock V12 front:
SR 466 lbs/in
FH not sure
heavy duty front (civilised fast road spring):
SR 652 lbs/in
FH 245mm (sits about 1.5 - 2 inches lower than stock)
super duty front (hard core fast road and track day):
SR 800 lbs/in
FH 230mm (sits about 1.5 - 2 inches lower than stock)
be careful with free height - very hard to preduct exactly where ride height will end up car to car. Often requires fine tuning with packers or even getting the spring reset to a new free height.
also, total number of turns assumes that both the top and bottom coils have a zero picth gap and consequently provide no effective contribution to spring rate, and are flat ground for spring seating.
I currently run the SD front, HD rear spring, 27mm front bar and 16mm back bar in my tarmac rally and circuit car, which has about the same weight on each end as an early stock V12 XJS, and it is pretty firm but not bone-shaking.
Hope this helps,
Andrew Robertson, New Zealand
Xj S1 454TT, Xj S1 383
From: “Travis Harper” firstname.lastname@example.org
Date: 2006/02/17 Fri PM 02:29:32 GMT+13:00
Subject: [racing] XJS spring specs???
Hello all, does anyone have the front and rear specifications for
the springs on the XJS V12.
//please trim quoted text to context only