I used to do front end alignments and built quite a few monster trucks. When
choosing a spring rate, test it without shocks with a certain amount of weight.
The job of the shock is to suppress spring oscillation, not to hold up the truck
in any fashion. It bothers me so much to see coil overs and air shocks on any
vehicle. That is a mickey mouse way of fixing a problem. I know there are going
to be disagreements here, but its the springs job to hold up the truck. In high
speed 2 wheel drive racing, a soft spring and a stiff shock works well, by
allowing the suspension to work its whole range while the shock keeps the
springs from oscillating too much. Have you noticed that some big trucks have no
shocks at all? That's because the springs are so stiff that they don't oscillate
much at all..
Robert Welch wrote:
> Mark, my son's 55 1st Series 1/2-ton (with Malibu front clip) weighs 3400
> lbs w/o driver. My 56 TF Cameo weighs 3570 lbs w/o driver and less than a
> 1/4 tank of gas. We weighed them both at the local landfill. As for the
> weight distribution, I can't help there. But the issue of spring rates is
> something I have been working on for some time.
>
> I have a customized IFS on my 56. The original frame was retained - tubular
> upper a-arms, 1x3 lower control arms, and positioning struts were added
> along with Carrera coilovers, Chevelle spindles and the Chevelle sway bar.
> This is essentially the same type of suspension oval track and dirt racers
> run (sans sway bar). We also added a MII Power R&P steering box. When the
> suspension was first done it was setup with 550 lbs springs. It was very
> stiff. I tried a set of 450 lb springs, naively thinking that surely a 100
> lb differential would make all the difference in the world with ride
> quality - wrong! The ride softened a bit but it was still way too stiff.
> To make a long story short, many years went by with that setup but I have
> been addressing the ride quality issue again just recently. Between my son
> (who has been active with the SAE Formula Car competition at college) and a
> local dirt track racer I have discovered a few things.
>
> It is now apparent that when the original IFS was designed (or constructed -
> I'm not sure how much design went into the thought process) in the mid to
> late 80's, stiff springs and stiff shock valving was the way oval track dirt
> cars were setup. Today, that is not the case. Drivers want to feel their
> suspension and understand exactly how their vehicle is performing and be
> right on the edge of being out of control. Consequently, much softer spring
> rates and dual shock valving are used to allow the vehicle to react. So I
> acquired a set of 300 lb springs and was again disappointed in the ride
> quality - it was noticeably better than the 450 springs but it just wasn't
> right. When we checked the shock valving in my coilovers I discovered they
> were a "7" (based on Carrera's scale of 1-9 then) which are considered
> x-stiff. This would appear to be the problem I have been having all along
> with ride quality - at least we think it is. I am waiting to receive
> another set of shocks that are valved softer and see how they react.
> Interestingly, I contacted Carrera tech support and their Street Rod guy
> recommended 450-500 lb springs for a vehicle weight of 2800-3000 lbs. At
> the time, I thought he was crazy. It may be that with the softer valving
> the 450 lb springs will be ok. In retrospect he may have been correct - I
> won't know until I try the new shocks.
>
> I guess my point of all this is be careful what combination you put together
> and understand all the components. Shock and coil spring travel length,
> shock valving, and spring rate all need to be considered for your particular
> application at the ride height you desire. After you have the ride height
> and shock/spring combination, you may need to re-address caster and camber
> issues.
>
> Bob Welch
> Bartlesville, OK
> '56 Cameo
> '55 Belair
>
> ----- Original Message -----
> From: "Mark Self" <markself@discover.net>
> To: "Oletrucks list" <oletrucks@autox.team.net>
> Sent: Wednesday, July 12, 2000 08:57 AM
> Subject: [oletrucks] 3100 AD weight - spring rate
>
> > Can any of you guys tell me the weight of a 3100 AD. I looked in the
> manual
> > and couldn't find it. The ID plate on the drivers side door post says
> GVWR
> > 4800 lbs. Since this is a half ton, does that mean that the truck empty
> > weioghs 3800 lbs.?
> >
> > Also do any of you knopw what the front to rear weight distribution is?
> I'm
> > trying to figure my spring rate for the front coils in the IFS.
> >
> > ====================
> > Mark Self
> > Redlands, CA
> > '55 1st 5-window 3100
> > "Sentimental Journey"
> > ====================
> >
> >
> > oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959
> >
>
> oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959
oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959
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