Is (front/back) 380/250 lb/in a stiff spring rate? was thinking about buying some ground control springs for my 94' integra, i wanted a decent race spring, im used to reading spring rates by "kg's" (thanks to Grand Turismo), so if someone could shead some light one the situation (approx. metric conversion) i would appreciate it

 

380/250 lb/in is something near 6.8/4.5 kg/mm. You basically just take the kg and multiply by 56, and vice versa. So 10 kg = 560 lb.

Those are off-the-shelf spring rates and are pretty soft. They'll ride fine for stock shocks, but aren't near "racing spring rates."

 

those rates are relatively mild. i have 400f 450r, which is firm, but not as bad as i was expecting them to be. IMO it's fine for daily commuting

 

everyones answer are correct but your shocks and your adjustment you can do with your suspension plays alot on how stiff your car is...

for example on my last car I had TEIN SuperStreets that was de-stroke 180mm in the front and 120mm in the back, and the were valved for 7kg in the front and 8kg in the back...

Because the Tein SS are twin tube and they dont adjust actual ride height... I had to un-load my springs soo I could corner balance the car. Which was a problem because even with the 7kg and 8kg spring from SWIFT... The car was still too soft for me ... The way to go is to make sure you can adjust ride height and spring load separately... And having MONO tube design shocks would be great too

 

spring rate is very personal taste, some ppl think it is too stiff, some think it is too soft. for me, i run 12k front and 8k rear, and it rides not bad as long as the piston position is set right. a coilover system with separate ride height and preload adjustment is ideal for easy tuning. a single adjustment is fine as long as the it got enough stroke after u set the ride height. i would say for a 2600lbs integra/eg civic, a 7 or 8k spring is not going to cut it if u drive aggressively.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RippSpeed &raquo;</TD></TR><TR><TD CLASS="quote"> The way to go is to make sure you can adjust ride height and spring load separately...</TD></TR></TABLE>

why?

I corner weight cars, pro and club racing, quite often and have zero issue doing it with only the spring perch.

 

wouldnt that unload the springs ??? and you lose some shock travel by doing so which would make the suspension be less effiecent...

 

yeah man, I run 8K fronts and 6K rears on the del Sol, and it is a little too silky smooth for my taste. If you want to know what hard feels like, talk to poison the hybrid *****. He is running 22k fronts and 18K rears on his 2060lbs H22 hatch. Its like he doesn't even have springs, just really stiff shocks. When his ITR brakes slam home @ 120, the nose doesn't even dip remotely. Its retarded.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RippSpeed &raquo;</TD></TR><TR><TD CLASS="quote">wouldnt that unload the springs ??? and you lose some shock travel by doing so which would make the suspension be less effiecent...</TD></TR></TABLE>

It's possible in extreme cases of lowering. In which case, your performance is shot anyways and the driver most likely doesn't care a whole lot about performance. But for anyone else, it's not really a deal breaker it seems.

 

yup but if you really look at the original posters question ... he is asking about spring rates... And that means he does care about performance... So thats why I posted my original post...

And my personnal prefference is running stiff suspension for a daily driver... I like it around 14kg in the front and maybe 16kg in the back ... But this would actually damage a cars chasis on the street because there is no flex in the suspension but theres flex in your chasis... This is the reason why I had my last car's chasis stitch welded DTM style ( one inch of weld for every four inches of seam)

 

i think PIC is not talking about the op, he is just trying to say when u drop it too much(while u need to unload the spring so much to get the rife height), then the performance will be down to drain. when u low the car so much, suspension is not work well anyway, since the roll center is lower than the ground.....

 

You wouldn't want to run any sort of stiff springs without upgrading the struts. The springs will overpower the struts and blow them out. All the car will do is bounce as it rolls down the road. If you stiffen on, you must stiffen all. Those stock struts can manage about 5K at the max, and that is really pushing it. Anything over that, you need a stronger strut to keep up with the springs.

 

Yes I was just speaking in general, because your question seemed to be about the design of suspension and not a specific question from the op.

 

understood...

I answered slammed_93_hatch's question...