----- Original Message -----
Sent: Wednesday, May 31, 2000 12:54
PM
Subject: Re: U2L Club class
Wayne,
Do you know what rate springs you are running in
your racer? If it is not giving too much away could you let me know what
brand springs you run etc and specs for them if you know and if you are happy
with them etc.....
Thanks,
Russ
Russ, Sorry, wouldnt have a clue
what the springs are in my 1600, as I brought it as an ex racer that needed a
lot of repairs.( Bushes, diffs etc).From what ive been told it was pretty good
handling beast. The springs in it now have the following
dimensions.
REAR
17 mm diameter coils
x 6 3/4 coils.
FRONT
10 mm diameter coils
x 5 3/4 coils.
You can calculate spring stiffness
by raising your coil diameter to the power of 4 then dividing by the number of
coils. This is only good for doing a comparison though.
eg. A spring of 10 mm diameter and
6 coils
10x10x10x10 divided by 6 = 1667
compared to the same spring, but
shorter (4.5 coils)
10x10x10x10 divided by 4.5 = 2222
This makes the shorter spring 1.3
times firmer.
You can use this
formula to compare spring rates.
(courtesy of Fast 4's &
Rotaries TECH TIPS #1, pare 91)
The following spring rates were recommended to
me.
SPRINGS
King springs are good, they also now make a progressive rate
front and rear spring for a 1600 (read 240k). Also a group in the US
called specialty enginneering for which I have a contact make a set of springs
specifically for racing a track 1600, lots of guys over there use these
springs and they are a proven commodity.
The spring rates also depend on how stiff your shell is, if
you have a cage in your car (I assume you do if your racing) or the body has
been seam welded, and some decent strut braces, all these things help stiffen
the car and the stiffer it is the higher spring rate you can run without
getting a twisted shell.
I have found these rates to be a good starting
point.
Rear Springs:
680ish lbs if you are running a decent road tyre and some good dampers (koni
adjustable)
800ish lbs if you can run slicks instead of road tyres.
Front Springs:
250lbs if you are running a decent road tyre and some good dampers (koni
adjustable)
280lbs if you are running slicks instaed of road tyres.
Hope it provides some
help
-Wayne
