I've got around 175 lbs in my trunk worth of stereo gear. This weight caused awkward wear on my Advans that I recently replaced. Any suggestions on a stiffer spring that would hold that weight better? Is there more to it than just springs? Even with that weight, I still feel like the car handles great, and that's through some SoCal canyons. So I don't really want to lose any handling. The easy answer is ditch the stereo, but for me that's not an option. Thanks.

ps...thanks Neil, I just got some RE750's from you guys and I really like them. Got here in two days and at a great price. TireRack RULES!!

 

Ok, after 30 views and not a single reply, let me add this. All I want to know is if the stock rear springs are rated at 225 lbs., and my box weighs ~175 lbs., does that mean I need springs rated at (175/2 + 225) = 312.5 lbs. in order to make the suspension think there is no box there? Is a ~310 lb. spring appropriate for the shocks? Do I need to look at coilover's? Anyone?

 

Please don't take this the wrong way, but have you tried reevaluating your needs as far as a system is concerned? Maybe losing a sub or redesigning the box to distribute the weight differently? Secondly, are you sure the wear is from the equipment? Just some thoughts. Good luck.

-J

 

i got an amp, and 12" woofer, with a box works for me, i know what you mean when i was running 2 (10s) with a box? it was heavy so i decided to go with single 12

 

Thanks, I have thought of some other options, but at this point I have too much time and money in my trunk. Besides, I think this is an easier solution then redesigning my system.

I understand that most people here are performance orienated, but this is a simple question that anyone with good suspension knowledge should know. I unfortunately don't have good suspension knowledge.

 

I would suggest merely getting a 4 wheel alignment done with the stereo present in the car. (Preferably with you sitting in the driver's seat as well - or at least equivalent weight in ballast.)

The stock springs on an Evo are stiffer than stock springs on most cars, and should be able to handle the extra weight no problem -- which makes me thing you've just got a bad alignment.

But anyway, if you're trying to mathematically figure out what springs to use to maintain stock ride height in the rear... The stock Evo carries about 40% of its 3263 pound weight on the rear tires -- that's about 1305 pounds. If you've got 175 pounds of additional weight all on the rear axle, you could go with a spring which is about 13.4% (175 divided by 1305) stiffer than stock, with same length as stock. That would restore ride height in the rear (with the load) to stock unladen ride height. If the stock rear springs are 225 lb/in, you'd go with 255 lb/in springs.

With those springs, the change in ride quality would probably be fairly subtle. The rear end would ride about 4/10 of an inch higher.

But like I said, check your alignment first before upgrading the suspension. 175 pounds is not a big load for the stock suspension to handle...

 

Thanks man , that's what I was looking for. I should have mentioned earlier that I did have an alignment when when I had my new tires put on. They couldn't make the alignment like the computer said because of the weight in the trunk. I figure that the weight loaded the suspension down and actually caused the rear tires to camber out. All Advans were worn to nothing on the inside, but still had about 3/16's on the outside.

 

That's surprising that they couldn't get a decent alignment... The rear camber of the car actually has a fairly wide range of adjustment.

The wearing away on the inside but not the outside indicates either too much negative camber or too much toe out. If it was toe out, the car would be very "spin-happy" when pushed, and in general would feel unstable. So you're probably right about the weight causing the negative camber to increase. If it's truly outside the camber adjustment range of the car, then stiffer rear springs could be one solution -- as long as you stay close to stock spring length, the alignment should be able to be tamed...

 

Thanks again, that's great advice.