I have a 87 Formula with WS6 suspension.

I've always found it way too hard (though handles a bit better than my 99z28). All the shocks are fairly new, but I need to change the front springs as one has broken.

These Moog springs to be equivalent of original but has a spring rate of 748 !!! -that's really hard compared to pretty much any cars I've compared and I think maybe even harder than stock (which would be unbearable), bearing in mind a stock 4th gen TransAm is closer to 300.

MOOG 5662 Formula & T/A (with 16" Wheels) Rate: 748

Has anyone tried this one in a V8 WS6 car -I'm hoping it will be similar ride height and a bit softer ride??

MOOG 5608 Formula & T/A (exc. 16" Wheels) Rate: 424

I'm just a bit worried as mine has 16" wheels and it says exc. 16" wheels -is it going to affect ride height? Thing is, smaller wheels usually have fatter tires so the ride height is about the same anyway I would have thought?


I'm in the UK and the supplier here has limited choice (though they or I could ship something else over if Moog is really no good).

Any ideas?
thanks

 

The original WS6 springs were in the neigborhood of 400 when new.

Keep in mind, the spring rate is given AT THE SPRING, meaning, if a different design suspension gives the wheel either more or less mechanical advantage on the spring, that will have the same effect as giving the spring either less or more rate, respectively. And the design issue includes the effect of wheel offset. So it's impossible to compare the spring rate #s on a 3rd gen to those of a 4th gen, directly.

The Moog 5662 or 5664 are the ones to get. For the rear, either 5665 (constant rate) or CC635 (variable rate). I have the 5664/CC635 combo on my car and love it.

Put new struts on the car, regardless of how "new" they are. (unless they have like less than 5000 miles or so) They make a HUGE difference. As well, since you have to have the ball joints apart, might as well renew those; and as long as you're that far, might as well put in new control arm bushings. All of those things will dramatically reduce the harshness of the ride.

 

4th gens have coil overs...the coil spring is "over" or around the shock/strut. the mechanical advantage mentioned above is a huge factor. shocks/struts normally attach to the suspension arm very close to the tire therefore a lower spring rate is required to achieve the same end result as a conventional coil spring setup like our cars use.
That being said, a 7xx lb spring in the front of one of our 3rd gens is by no means excessive. A 300 or 400lb spring in the front of our cars probably would not work too well. It would take a very tall spring to hold the nose up at the desired height without collapsing too far.

 

these cars dont ride smooth, just the way it is. the harsh ride has more to do with the shocks than the springs. I have 1050 lb springs in the front of my 86 and its far from what i would call rough. Crappy shocks will make the car ride like crap and they wont live long anyway, and a broken spring will cause the rate to increase a lot, so that can add to the harness. It should not be anywhere near the realm of "unbearable", but the car will never ride like a modern car.

the factory v6 springs are 425ish lbs, so i dont see how the ws6 springs could be less than that.

The moog springs will probably raise the car, they always seem to.

 

Thanks for your advice guys. The car's not been used for about 4 years but the shocks only have a few 1000 miles on them so probably isn't worth swapping them out yet. I'll certainly change the control arm bushings though -good idea.

Yeah, I drive the 4th gen as a daily car and I guess I was trying to make it ride more like that which is totally different.

You're probably right -the spring might have been broken a long time so it's not surprising it feels like driving a flintstones car.

Ok, think I'll stick with the 5662s as if I start messing putting softer springs in, the roll bars etc won't be designed for each other and I might end up with new, unexpected problems.