SStoRX8

Hey guys, so I recently purchased some new tires because I noticed my rears were getting a little bald, so the other day as I was installing my BHR midpipe, I noticed my rear tires both went flat, and I took them off and saw that the insides of the tires were completely bald and torn in some areas, exposing the metal. The guy at the tire shop told me that's a sign of bad rear shocks, is this true? The fronts have no issues, only the rear, so could it be in need of an alignment?

SStoRX8

Btw these are my old tires that tore, after I saw they were flat I removed the wheels and had the new tires put on them.

RIWWP

iTrader: (2)

Is there anything in the rear wheel wells on the suspension components which are showing signs of rubbing? Polished metal, transfered rubber, etc...

J8635621

iTrader: (10)

Alignment is a big deal. And so is rotating tires. I see no mention of these two things.

SStoRX8

Not that I can see no, the rear tires are however slanted, the bottom juts out while the top goes in slightly. Oh and the BHR midpipe is awesome haha, thanks for the suggestion.

SStoRX8

Yeah of course, but this car had an alignment about 10k miles ago before I purchased the car, the old owner gave me the paperwork from the Mazda dealer.

J8635621

iTrader: (10)

Slightly is not very scientific. Your description is that of negative camber. You are supposed to have some. Toe in is harder to see but even more important to wear

J8635621

iTrader: (10)

There are tires that can wear out in 10k miles all on their own. What tires do you have? How many miles are on them? What specs was the car aligned to? Were they ever rotated? What kind of suspension was on the car and has it always been that suspension? How many miles on the car?

SStoRX8

Yeah I'm not very familiar with suspension, most of my work consists of engine and exhaust work. Okay so it's normal to have some negative camber on these cars?

J8635621

iTrader: (10)

Absolutely. Most cars are that way. Considerable amount of negative camber? No. Without an actual reading it is hard to know.

SStoRX8

The car itself has about 97k on it, all stock suspension, they were goodyear tires, the fronts are still about 60%, although I'm not sure if they've been rotated. The sheet he gave me says this for the rear:
Rear: Left- Actual -1.4 degrees 0.19 degrees Before- -1.4 degrees 0.19 degrees.
Rear: Right- Actual- -1.5 degrees 0.21 degrees Before- -1.5 degrees 0.22 degrees

SStoRX8

Cross Camber Total Toe Thrust Angle:
Actual: 0.1 degrees 0.40 degrees -0.01 degrees
Before: 0.1 degrees 0.40 degrees -0.02 degrees

Ride Height: 14.5" for both sides.

J8635621

iTrader: (10)

I wouldn't be surprised if your struts need replaced. I don't have the normal alignment specs in memory but that seems excessive. It looks like their alignment didn't adjust anything either. Does the rear of the car sag down? Ride really bouncy? Not sure you have an appropriate baseline to know lol

SStoRX8

The rear does sag a little, there's less space between the rear tires and the body than the front, I'm talking about half as much, I can barely fit my hand horizontally. As for the bouncy ride you're right lol, I can't really determine, I've never driven an RX8 until I got mine :P But I guess you could say it feels a bit spongy going over speed bumps.

J8635621

iTrader: (10)

Yea sounds like the rears are hurting. Here is my suggestion.....new struts all around and springs too if you wanted to be lowered. Then get an alignment at a place that will do the specs you give them (like a place that autocrossers or track guys would go to). They are usually pretty reasonable as far as alignments go. Suspension is the main thing the rx8 has going for it so do it right. There are threads here that discuss great alignment settings.

There are multiple options for springs depending on the ride height you are going for. Coilovers are an option too but more expensive if you get ones worth getting.

SStoRX8

Yeah I was considering just changing them all out if I was going to have to change the rears, might as well. I wouldn't want the ride very low, its current height is pretty nice, maybe half an inch lower wouldn't hurt. As far as struts go, I heard KYB makes good ones for our cars, or should I just get new stock struts?

J8635621

iTrader: (10)

Bilstein is what I would get. S-techs are a common spring to choose. KYB is probably fine. Stock is fine. Tokico is fine. Koni lowers the car a bit extra and I've heard of people having failures with them. I have no idea what any of them cost though.

SStoRX8

S-techs are the Tein springs correct? Hmm so all together the struts and springs should run me about $700, damn lol, a lot more expensive than struts and shocks on my old SS xD

J8635621

iTrader: (10)

Post a side profile shot of the car please. Just want to verify that the rear looks like it is sagging.

SStoRX8

Alright no problem, just give me a few minutes.

SStoRX8

Front:
[IMG][/IMG]

Rear:
[IMG][/IMG]

The front I can fit about 3 fingers vertically, the rear only about one, oh and I couldn't get an entire sideview of the car right now, it's in a tight area. And I apologize in advance for the crappy camera quality lol.

SStoRX8

Oh and the picture of the rear isn't as level as the picture of the front, I'm not very good at this lol.

J8635621

iTrader: (10)

Hard to tell and it's been a while since I was stock......

I'd say get a lifetime alignment somewhere and reduce the toe to 0 or very very close to it and put the camber closer to -1. Get struts when you can.

SStoRX8

I'll do just that, and hopefully I'll get the new struts and springs as soon as possible, thanks a lot for your help man.

J8635621

iTrader: (10)

I said lifetime alignment so that you can get it aligned after the struts/springs too. (install yourself if you are halfway mechanically inclined). Look up the robin yang DIY webpage and set aside a full saturday. The alignment after messing with the suspesion is important lol. Look up good alignments on this forum. There is plenty of info. Just use what I said as weak guidance in the correct direction.