Since this is the tech thread, I'll reply here...
Quote:
|
Originally Posted by scoobanader
i got coilovers from guilbert for 100 bucks so i went ahead and bought them because i knew i could sell them for more then that if i did not like them. when my car was stock i was having camber problems. i had positve camber so i decided to lower my car with new springs so i could get a litter better tire ware and it would look a little more agressive. the car still had ware on the outside of the tires and i was able to notice by eaye that it still had a little bt of positve camber and guilbert from guilsons said he had a set of ground control coil overs for a 100 bucks. so i went ahead and got them and installed them. the car now has a little bit of negitve camber witch i want but because of the height of my car(very low) my stock struts are not doing them what i want them to do, so i am going to go with the tenabe 5way ajustable struts. the cars alinement is fine but the car is a little bouncy. i took a couple corners to see if the car handled better...it did handle slightly better but i did not put the new coils in the back yet(just the lowering springs due from lack of time) so the car is getting some understeer. i think when i do the coils in the back it will tighten up the rear of the car so it will be a little looser(right?!?) i am sure with the new struts with the ground control coil overs it will do the job for right now, it will give it a little better handling, more agressive stance and get rid of my positve camber problems...in responce to libala, i need some new brake pads, mine are prety wore out, and as well as the tires.
|
1st... I swear to god, this looks like an ESL student... if I were your english teacher, I'd fail you. It's been said before, on a forum all we have to go by is your written word, the way you type directly effects the results and replies you get. Typos, minor mistakes, occasional spelling error... no big deal... but this is pretty hard to read. However, I think I know what you're trying to say so I'll answer as best as I can.
I'm assuming the GC "coilovers" you got are height adjustable sleeves and springs, yes? If that's the case, you need to be careful with the height you choose to run them at. Lowering the car may make it look better, and may make the handling seem better, but chances are it's not going to grip nearly as well as it did stock.
1st of all the stock struts are designed to work with a particular spring rate, at a particular height. When you stray too far from these parameters, the stock struts are forced to operate in a way they weren't designed to handle.
Let's look at spring rates. If you go up a lot in spring rate on stock struts, you end up over-powering the strut's ability to prevent bounce. Many people believe that the stock STi struts are a little to hard for the stock springs, so you probably have a bit of room to go for a stiffer spring than on other cars, but I'll bet anything more than 10% - 15% stiffer is too stiff and will lead to underdamping. Reports are that the STi pink springs (like the ones MattR put on his STi) are actually the best match to the STi struts... they're just slightly stiffer than the stock springs. (I don't remember the rates, if anyone knows them post 'em up!)
Now let's look at the ride height. A strut is designed to be at a certain length when it's at rest. At this "ideal" height there is adequate throw on both the compression and rebound side of the strut. When you lower the car excessively, the strut is forces to rest at a shorter length than it was designed to. So when you hit bumps, not only is the valving potentially not quite right to damp the spring, you also have a much greater chance of running out of travel and hitting the bump-stop. Plus when the strut is operated at a less than ideal length, you will wear it out much quicker than normal.
So, if you're using the GC's with a stiff spring at a low ride height, you will probably get a harsh, bouncy ride, and quickly wear out the stock struts.
However, there are some advantages to a GC sleeve setup. Because they are height adjustable, you can use that and a set of automotive scales to corner weight the car. If you use springs close to the OEM spring rates, as well as leave the ride height near stock levels, then get the car corner balanced, you will have a handling demon. The STi has terrific suspension right out of the box (save the excessive understeer that Subaru builds into it). By going a bit stiffer, and getting things balanced, the car should handle well, for relatively cheap.
Getting to the alignment and tire wear issues. You used to have lowering springs on the car, yes? IIRC they were pretty low too, weren't they? Anytime you lower the car, you will run into alignment issues. Without camber bolts and/or adjustable strut tops and/or adjustable lateral links, you will probably end up with camber outside of the stock specs. Specifically, IIRC, Subaru's tend to gain positive camber when lowered too much... (that sounds contrary to what I would think would happen, but that's been my experience). So you could have been out of alignment due to your lowering springs... and going even lower with the GC's would be even worse. Positive camber will indeed wear the outsides of the tires, plus it will also generate toe-in with is also bad for the tires. Also, hard driving on a "street" alignment will result in worn outsides of the tires.
So, if you really want to go low there are some things you need to do.
1) Get struts that are matched to the height and spring rate you plan to use.
2) Use stiffer springs to prevent bottoming out
3) Use camber bolts, adjustable strut tops, and/or adjustable lateral links (in the rear) to deal with the camber issues.
It sounds like you've got #2 taken care of with the GTC sleeves/springs. You mentioned going to some adjustable struts. If they're matched properly with the GC's then you've got #1 covered, and that will make a world of difference. I'm not sure if the GC's came with adjustable strut tops (doesn't sound like it at that price). GC makes some great caster/camber strut tops that would work with the sleeves and struts, and that would take care of the camber issues up front. I'm using H&R camber bolts in the rear of my car to help with the camber... you might want to try those, or some adjustable lateral links in the rear like Dean's using are another good solution, albeit much more expensive (but they have other advantages too).
Finally, you should talk to Nate at S-Squared... he's the man (used to work for Ground Control developing suspension kits for cars). Not only can he get your car lower than shit, he can make it handle too. You should see how low his shop car is, and it's on GC sleeves, GC top mounts, and Koni inserts IIRC... a very similar setup to what you're working on.