WhiteKnight '01

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So I got a brand new set of tires on my '01 Z28. Firestone Firehawk Wide-Oval Indy 500 tires, they seem to be a good tire with good traction, and handling is decent, but it seems like at speeds over 70MPH if I wiggle the steering wheel a little bit the back end sways and wobbles a bit. This was greatly increased by checking the tire pressure and setting it to 36PSI, rather than 46 which came in the tires when I bought it. They are 245/50-16, original equipment tire size. However I was wondering about some other things to increase my handling. Here are some things I have thought about.

1. Tower strut brace bar - I believe this goes in the engine bay, anyone know exactly what this does and how much it helps? Is it worth it?

2. Panhard bar - I heard this goes in the back, near the axle I believe, and it keeps the rear end of the car aligned with the front end of the car, so the rear end becomes better balances and predictable, I think. Is this true? Is it worth it?

3. Sway bars - Front and rear sway bars, I think thicker is better, but is there a a preferred brand or certain size I should aim for? Should I keep the stock bushings or go for polyurtherane ones? And how does this help the car's handling?

4. Tie rods - I've heard the inner tie rods affect steering tightness, do they really? And do they do anything else in the handling department?

5. Shocks - I have brand new bilstein shocks on all 4 wheels, they barely have 10,000 miles on them.

Is there anything else I can add or change to increase my handling? All ideas and advice is appreciated, thank you.

camarokid91

Sway Bars are good place to start people typically run 35mm in the front and a 21mm in the back. BMR and Stranos are common brands.

redbird555

iTrader: (14)

I think if your concerned with the "swaying" or roll of the car, which it seems you are I'd go with new sway bars. Strano offers a nice set usually the preferred is 35mm up front and 22 out back this will greatly decrease the body roll on the street and in turns puloy bushings in those areas only would be nice also.

The panhard bar is really to just give a little more stiffness and get the rear end centered for wide tires. Another thing you could also look into is a Watts link as that completely limits the movement of the rear end and really changes the hadnling aspects of the car.

z28bryan

iTrader: (7)

From reading tirerack reviews, the general consensus on those tires is their sidewalls are pretty soft. So I'm going with soft sidewalls as being the culprit. Plus you're on a 16 inch wheel/tire which makes it worse. It's probably similar to driving on some of the winter tires I've driven on on my Camaro with the 16s.. even my BMW with the 16s feels wobbly on the winter tires and it's got the sport suspension.

I don't think its the swaybars. While the sways will allow more roll, at least they should feel stable. The Bilstiens should keep the car under control very well.

You could change other things, but I believe you still still feel unstable until you ditch those tires. Sorry, probably not what you wanted to hear

z28bryan

iTrader: (7)

Also.. just wondering. Did your car not feel as wobbly before you changed the tires? What type of tires did you have before?

WhiteKnight '01

The car has almost always suffered from this wobbly feeling. At cruising speeds of 65-70MPH and in hot weather the car feels somewhat wobbly when tilting the wheel to the left or right, the rear end sways a bit. However, at night time when the temperatures are cooler the car feels much stiffer and more nimble. Part of this problem was addressed by lowering the tire pressure. The idiots at Firestone loaded the tires with 46PSI in the back left and 40PSI in the other 3, reducing it to 32-35PSI has helped it a lot, but not completely.

My previous tires were a cheap set of Fuzion tires, only cost $96 a tire I think, these Wide Ovals were $120 per tire, and have pretty good traction for a street car. They're considered the low profile tire, because they are a 245/50-16, so the top tier of low profile tires, and they're factory equipment sizes.

I had been thinking of upgrading the car to the 17 inch rims, seems like there's a lot more tires to choose from in that tire size. Would the sidewalls be stiffer and the slightly taller tires increase handling a bit?

Carlos01SS

iTrader: (4)

Going to the 17" wheels is actually a good idea, in 01 & 02 the 17"X9.5" wheels were coupled with 275-40-17" tires, ride height will still be close to whatchu got now but with less sidewall, two things will occur:
1.). Your car will feel much more stable and responsive due to less sidewall compared to the 50 series tires you got right now, will lessen the wallowy feeling that u got right now
2.). It won't feel as plushy smooth due to less sidewall, bumps will feel more harsh

OH!!!
3.). Your car will track grooves more due to the wider tires especially when you're close to wearing out your tires.

WELL worth it though IMHO

Sam Strano

iTrader: (41)

The fact the car is better when it's cold points to shocks. The oil in the shocks is thicker, adding damping force. This happens with all shocks, though with Koni's you could get that extra damping control when it's warm too.

That said, whether or not you would be up for a shock change you'd love a set of 35/22 bars. The roll stiffness would increase greatly. The car will be more stable, react quicker, and of course roll less. And it's balanced. You don't want too stiff a rear bar (like a 25mm). You can really still trust the rear end of the car when you run my combination of bars. They are well proven, I've been doing them for years.

Just to be clear: Shocks control how fast you generate motion, and how the motion is damped out. The bars control how much roll you get (along with the springs), but not how fast what roll you get is generated. Because you like the feel of the car better when it's colder that tells me that your desire is likely more one of greater shock control than lesser body roll. Not that less roll is bad either way. It's not an either/or thing. You can do them both....

Latch

iTrader: (8)

If you've already spent the money on Bilsteins, the next upgrade is a set of bars. Get you some Stranos.

leadfoot4

iTrader: (1)

The car is over 10 years old...how many miles are on it? Control arm bushings, panhard bar bushings and ball joints don't last forever, and they are the basics for a good handling car. All the fancy shocks, swaybars, etc will only do so much, if the "pivot points" of the suspension are worn out due to miles or dried out due to age....

garygnu

.maybe have your front alignment checked.check your suspension bushings for wear .consider some new bushing for the sway bar links.