Spring rate needed... Help!

fxbill · #1 (**permalink**) 11-16-2010, 10:29 PM

Hi,
It's been a long time since I've been here and just sold my CR yesterday, but need some info for it if anyone can help.
Initially I had 15" wheels on the car and installed upper and lower adjustable "A" arms on the front. I used the coil over shocks and springs that Don was selling for the cars at the time. It was an off brand that he got a good deal on and they worked quite well. I changed to Team Three 17" wheels though and now the suspension is way too stiff up front. The anti sway bar was removed long ago when Don felt it was a smart move for a better riding car. It's an early model with the big block tunnel.
Does anyone know what the spring rate was on the coil over shocks he was selling and/or does anyone know about what rate I would need to soften up the ride? It's running a Dart Iron Eagle 351W block to give you an approximate weight idea of the engine.
Any help would be greatly appreciated.
I'm pretty sure that Double Venom knows what Don was using so if you happen to read this could you possibly help me out?
Thanks in advance,
Bill

Tim Brewer · #2 (**permalink**) 11-16-2010, 10:47 PM

Well, going from 15" to 17" wheels won't make your car stiff, except the fact that you will have a little less rubber between the wheel and the road. You may have annother problem. An average front spring rate is 350#.

fxbill · #3 (**permalink**) 11-16-2010, 11:19 PM

Thanks Tim, but yes, it did make a big difference. The 15 tire gave the car quite a bit of cushion and bumps and small pot holes weren't a big problem, but as soon as the 17s went on it started riding like a truck! 350 is a good starting point though and I can measure these and possibly soften them up a bit. I don't own the car as of today, but would like to help the new owner out as much as I can. I can't remember what Don originally sent these with, but can pull one and measure it and go from there. I just don't want to get too involved in the car again since after owning it for over 10 years it's time for someone else to take the helm. He's new to these though and I'd like to offer what help I can without going overboard. I appreciate your input!
Regards,
Bill

Double Venom · #4 (**permalink**) 11-17-2010, 03:08 AM

fxbill,

Usually the 350 lb. rate was for any small block. BB's were anything upwards to 550 lbs. If Don picked your springs out I would guess they are the 450's to 550 range?

DV
PS. The rates should be stamped on the bottom of the coil. Height of the coil isn't much good for determining spring rate.