dbs1vette

For those who have done enough of both, what is your expert opinion? Issues solved? Issues created?

crimlwC6

Not an expert but I've run square setups for years. Matter of personal taste, square means oversteer is going to happen.

sean.b

but at the same time if you square up on wider tires, it can handle it a little better, the smaller sidewall ratio increases turn in (adding to oversteer, but it has a snappier feel) etc.

a lot of people will run staggered or square depending on the track. if you're going for a perm setup, or street the car, you're probably better off staggered.

if you just dont give a damn and want one single setup and dont care if it rut hunts or handles poorly in rain, rock on with a square

18x10.5 on 285/35/18 here

RDnomorecobra

It will add oversteer, but think about it, there is understeer baked into the stock setup so in my experience it tends to move it more toward neutral. I have a stock c5z with '04 shocks, stock springs, and T1 sways. I run 315/30 and or 305/30 or 35's. Track alignment and car is very neutral.

dbs1vette

Well the 07 Z I had, had a nasty habit of snap oversteer and I DANGED sure did NOT like that. On this 04 Z I run nitto nt-01 315/30/18 rear and 275/40/17 front and the first couple of short tracks it handled very well. Then we went to a little longer track and it was everywhere.

It could have been the tires finally running out of tread, or the rear main dropping a little oil on the rear, but...not good.

With it being 70% street car and 30% track it sounds as if I'd be best served staying with what wheels and track tires I currently run, and I'm due for some new tires.

Thanks for all the info!!!

Dan H.

subscribed

One of my winter to-dos is pick up some rear wheels/tires and get a track/street alignment.

JeremyGSU

When I first bought my '04 Z I was running 275/40/17's and 305/35/18's with Nitto NT555 RII's. I thought the car had noticeable understeer with this setup.

I then add the JOC Stage 1 suspension and felt that a lot of the understeer was reduced, however it was still there when really pushed.

I then swapped the JOC shocks for Doug Rippie and went to 18's in the front.

I now run 285/35/18's in the front and 305/35/18's in the back and I think the car handles much better. Understeer has essentially been eliminated and the car is very predictable.

The reason I haven't gone wider in the front is I read it was harder on the stock steering pump and would reduce its life. Not sure if it's true or not but didn't want to chance it since my car is still a street car.

Bill Dearborn

Go with a square setup. When I first starting running C5s in 97 I noticed they understeered less than my 86 C4 did but had a greater tendency for trailing throttle oversteer that at first was unnerving. That was on stock size tires. Then I went to 275/315 front/rear on C4 GS wheels for my 97 that I carried over to 03Z for a couple of years. With that setup the understeer was about the same but the trailing throttle oversteer became more manageable and actually usable. After two years running that setup on the Z I went to 315 square on 17x11 C4 GS wheels. The difference was night and day. The understeer was reduced so I picked up speed on corner entry and mid corner while trailing throttle oversteer seemed to be about the same. The car became a track and autocross monster. On the track it was phenomenal on an autocross course it was a shade slower than the 86 had been but still allowed me to set many FTDs over the years I ran the car. After a few years I couldn't get any more Kumho 315/17 710s at a reasonable price so moved to a square setup with C5Z rear wheels running 305 Hoosiers. Equipped that way the car was never as fast as it was with the square 315 setup.

Bill

sean.b

ive noticed a stack lack of 315s lately, and when you do find them, they're insanely expensive. i was hoping to hear anything but what you just said, with the extra 30mm being that noticeable :/ just ordered 285 hankook rs3's, after reading a lot of guys here winning events with them. ill let you know after Oct 4th..