Tranzor

Ok, I went out on Hwy 167 the other day to test out my new tune from James... and I when I went WOT in 4th gear, I couldn't really look at my Predator data because the damn rear end was skipping in and out of the ruts on the road!

Man... I forgot just how crappy our roads are around here because my 275s I had on before fit a lot better in those grooves... these 295/35/18s don't fit at all!

For any of you that don't have fatties in the back yet, just remember... hold on to that wheel real tight when you floor it on our freeways!

Poik

Yeah when I switched from 245 all around to 275 and 315s.. Wow, it's like the car is on rails, and not in the good way! Especially that area of road just north of Lynnwood, I feel like I am going to get flung into another car every time.

burbman

Try it with 305's all the way around. Makes you wonder what just broke in the steering box.

Tranzor

heh... I can imagine. At least I have 265s up front, so the front was holding steady. However the rear was trying to yank the car into the other lanes.

DrEvyl

iTrader: (5)

The stretch of road between Olympia and Centralia used to be absolute HELL for F-bodies before they resurfaced it. The ruts were really bad. I had 285's on my Trans Am, and when I changed lanes it was like being launched out of the lane into the other...

Damn scary.

93TAWicked1

iTrader: (28)

You know its kinda wierd. 315 nittos on the WS6 and it was ALL over the place. You had to pay attention on the highway although if you go faster it seemed to smooth out.

The Z06 with 295 tracks straight. Its responsive so you can just go to sleep there is not play in the steering but if you hold it tight it goes straight pretty good.

A good alignmnent will help f-body with the rut steer but I wonder what else is playing a role in the vette not having the same problem... IRS?

Shoot even going from 245's to 17 inch 275's I noticed a difference in the 93 and the 98...

WAHUSKER

iTrader: (4)

And dumping your STB didn't help matters either Jason!

Tranzor

The front of the car is fine... can't tell the difference between STB on and off. I think that's because the tires up front are actually skinnier than the ones I had on before (265s vs. 275s). It's the damn rear of the car that squirrels all over the place in those ruts.

Probably has something to do with my big *** 25mm sway bar... that can't be helping those big *** tires with the freeway ruts.

Tranzor

I'm thinking the IRS is a big plus for you over me with the same size tires... my axle bucks when hitting those ruts, while your IRS is flexing nicely to allow for the uneven road.

And a front alignment did help me before... but you can't really do any kind of alignment with the rear, being solid rear axle and all, except maybe adjusting the panhard here and there.

97BlackT\A

That's why my wife won't drive my car on the freeway anymore, although they did fix the worse areas of I205.
Her exact words were, " I looked over to the right to change lanes and the car went LEFT!"
I felt like an ***. I totally forgot to tell it was a handful in the ruts.

Thank goodness the left lane was empty....

Rokko

iTrader: (2)

That stretch of I-5 from 164th to past the mall is fookin pathetic. That's a both hands on the wheel area.

I think the Vettes might be better on these if they have a narrower wheelbase. Is this the case? Do the y-bods have a narrower wheelbase than the f-bods?

ram-it

One thing about fat rear tires is to let them do their thing. Even when you think its going to throw you onto the dividing line just hold the wheel. It will come back. No matter what you do you will look drunk driving I5 north around 164th. Just hold the wheel and feel what the car is doing. They preach listening to the car at driving school and feel what it is telling you. Hold the wheel. Minimum steering input is all that is needed. I know that is hard to remember when riding next to a semi but trust me. I have been running 315's and those 295's on I5 for over 50k miles. I used to be jerky with it but had to learn to be smooth.

ram-it

The y-bodies have a longer wheel base than the f-bodies I think. But don't quote me. Having owned both they are damn near identical in how they react in that stretch of road.

WAHUSKER

iTrader: (4)

My car wasn't too bad with the ruts until I put 315s on the back. And then when I put the STB on the front it settled down quite a bit. But then I tend to drive like Eric was talking about. Just hold the steering wheel steady & let the car come back home.

IMO this issue is all about play....slop....whatever you want to call it. And I'm talking front + rear combined. True, bigger tires grab the ruts & throw you around. And the tires being different widths make sit worse cuz they don't track each other. But the front IS in control. That is why Vettes & Porches don't seem to have as big a problem. Their suspension is tighter.

And I don't think your big rear sway bar has much affect on lateral side-to-side movement. It's for keeping both sides on the same plane horizontally. So under torque the right rear tire doesn't lift off the ground. Tho trackbird & mitchx say a big rear sway bar makes cars with 315s more stable in the turns.

Now a big front sway bar might actually affect this slightly....in a good way.