Jump to content

Square Tire Set-Up


MidNiteFury01

Recommended Posts

MidNiteFury01

is a tire combination which has identical sizes on all corners. Anyone running a set-up like this on a C5 / C6? Most folks that have a square set-up are running 18's on all fours such as 295 / 35 / 18 and seem to do allot of track work & autocrossing events.

I suspect there will be some rut hunting while driving, but would it reduce the understeer normally present in the Vettes?

Link to comment
Share on other sites

I'd think it would throw the active handling handling out of whack due to wheel speed sensors being out of parameter. Dedicated track car I could see

Link to comment
Share on other sites

I would think some different sway bars or adjustable socks would be the way to dial out any understeer.

If I sway at the bar I slip on my socks too.

Link to comment
Share on other sites

I have driven my wife's 04 on track with 275 40 17's on all 4. I found the car well balanced with a hint of oversteer. This was on bondo west, scooting around the paddock, a basically constant, fast right hander. It is not a throttle induced oversteer. The oversteer gets real stupid, real fast.I have not driven it on track with the factory 245 17 front and 275 18 in the rear. But would assume it would be a bit snug in the front. Maybe disconnecting the rear sway bar would balance the car a little more.

Link to comment
Share on other sites

MidNiteFury01

I have driven my wife's 04 on track with 275 40 17's on all 4. I found the car well balanced with a hint of oversteer. This was on bondo west, scooting around the paddock, a basically constant, fast right hander. It is not a throttle induced oversteer. The oversteer gets real stupid, real fast.I have not driven it on track with the factory 245 17 front and 275 18 in the rear. But would assume it would be a bit snug in the front. Maybe disconnecting the rear sway bar would balance the car a little more.

It's the oversteer part that I'm not to fond of, especially real stupid, real fast oversteer.

Various references state engineers induce "safety related" understeer within the Vettes to minimize spinning out (becoming dynamically unstable). It's not that I don't want the understeer, its that I want to increase the frictional boundaries to the maximum without inducing oversteer conditions. Whats too wide of a contact patch, or is it simply keeping the front contact patch just slighter more narrow than the rears - will that bring the car to a more neutral state w/o inducing stupid fast oversteer?

Various classes limit the amount of vehicle changes - i.e. adjustable shocks & coil-overs which places one in a race-prep / modified category. My car is surely no where near that, nor is the driver...

Link to comment
Share on other sites

I'm running square for auto-x on teh Z-28, 295's all around on 18x10.5 C5 Z06 wheels (with 2" spacers), teh oversteer is near negligible.

Link to comment
Share on other sites

MidNiteFury01

I'm running square for auto-x on teh Z-28, 295's all around on 18x10.5 C5 Z06 wheels (with 2" spacers), teh oversteer is near negligible.

you & I need to do some chatting. Seems like you have a near balanced ride then. Do you auto-x w/Tucson group at Marana or NCCC? I was thinking 295 all around as well on C5 ZO6's in the near future.

Link to comment
Share on other sites

Dropped a set of 19", all four corners on our '04 coupe after we bought it last year. 275/30 up front, 305/30 out back. Seems to handle just fine.

Chas

Link to comment
Share on other sites

Dropped a set of 19", all four corners on our '04 coupe after we bought it last year. 275/30 up front, 305/30 out back. Seems to handle just fine.

Chas

I have a similar set up with 18s, but that is not a true square set up because the front and rear tires are different sizes. Ben is looking for what Shifty has which is a true square setup - wheels the same size and tires the same size all the way around.

Link to comment
Share on other sites

I'm running square for auto-x on teh Z-28, 295's all around on 18x10.5 C5 Z06 wheels (with 2" spacers), teh oversteer is near negligible.

you & I need to do some chatting. Seems like you have a near balanced ride then. Do you auto-x w/Tucson group at Marana or NCCC? I was thinking 295 all around as well on C5 ZO6's in the near future.

It might be teh difference between Y-body and F--Body...come to think of it, I did try them on the C5 (with 1/4" spacers to clear teh C6-Z0 calipers), and it didn't feel as nice, though it was only on teh street.

When I could, I'd hit teh Marana airport auto-x....

Link to comment
Share on other sites

I think going square is more a tire rotation and purchase issue, there are way to many varibles involved to say putting smaller tires on the rear will cure oversteer.

If you really want to control it, move weight forward, having a 50/50 balanced rearwheel drive with plenty oh HP will make the rear happy.

Try this, go into a sweeper faster than normal, but don't touch the brakes or throttle, sure your going to slide but it will be very controllable with no braking or acceleration forces to throw off the balance of a stock setup.

So now you want to power out of that corner, less weight on the rear will do 2 things, limit your input and if it does start to oversteer there will be less of a pendulum affect.

Now that you have more weight on the nose and you can power out of any corner with no stupid drift effect but your understeering more, then play with tire pressures.

p.s. I can also help with your holiday shopping at Jared's...

Link to comment
Share on other sites

I have driven my wife's 04 on track with 275 40 17's on all 4. I found the car well balanced with a hint of oversteer. This was on bondo west, scooting around the paddock, a basically constant, fast right hander. It is not a throttle induced oversteer. The oversteer gets real stupid, real fast.I have not driven it on track with the factory 245 17 front and 275 18 in the rear. But would assume it would be a bit snug in the front. Maybe disconnecting the rear sway bar would balance the car a little more.

It's the oversteer part that I'm not to fond of, especially real stupid, real fast oversteer.

Various references state engineers induce "safety related" understeer within the Vettes to minimize spinning out (becoming dynamically unstable). It's not that I don't want the understeer, its that I want to increase the frictional boundaries to the maximum without inducing oversteer conditions. Whats too wide of a contact patch, or is it simply keeping the front contact patch just slighter more narrow than the rears - will that bring the car to a more neutral state w/o inducing stupid fast oversteer?

Various classes limit the amount of vehicle changes - i.e. adjustable shocks & coil-overs which places one in a race-prep / modified category. My car is surely no where near that, nor is the driver...

dale68z's mention of the oversteer at the sweeper Bondo West is a little confusing, EVERY car that exits that right hander at speed experiences wild oversteer! my favorite corner of all our local tracks.

try messing with your camber/toe settings. costs you nothing and makes a huge difference.

Camber - 2.5* up front and 1* in back

Toe - 1/8" OUT in front and 1/8" IN in back

if you have never done this before, ask for help!!

also, it is possible to help the car turn using the brakes and/or throttle... the driver mod is FREE!

Brake Oversteer pic attached - Also Bond West

post-2121-0-48073900-1418749880_thumb.jp

Link to comment
Share on other sites

MidNiteFury01

Dropped a set of 19", all four corners on our '04 coupe after we bought it last year. 275/30 up front, 305/30 out back. Seems to handle just fine.

Chas

I have a similar set up with 18s, but that is not a true square set up because the front and rear tires are different sizes. Ben is looking for what Shifty has which is a true square setup - wheels the same size and tires the same size all the way around.

Exactly Donna! I would like to consider 18" all the way around and put on 295's but leery of the oversteer condition...

I think going square is more a tire rotation and purchase issue, there are way to many varibles involved to say putting smaller tires on the rear will cure oversteer.

If you really want to control it, move weight forward, having a 50/50 balanced rearwheel drive with plenty oh HP will make the rear happy.

Try this, go into a sweeper faster than normal, but don't touch the brakes or throttle, sure your going to slide but it will be very controllable with no braking or acceleration forces to throw off the balance of a stock setup.

So now you want to power out of that corner, less weight on the rear will do 2 things, limit your input and if it does start to oversteer there will be less of a pendulum affect.

Now that you have more weight on the nose and you can power out of any corner with no stupid drift effect but your understeering more, then play with tire pressures.

p.s. I can also help with your holiday shopping at Jared's...

I just lost 40lbs so know you are telling me to get fat again to shift the weight forward? Holy hell, I think we better stick to shopping at Jareds. I don't know what smaller tires on the rear would do? That would certainly induce more oversteer don't you think or did you mean something else?

I have driven my wife's 04 on track with 275 40 17's on all 4. I found the car well balanced with a hint of oversteer. This was on bondo west, scooting around the paddock, a basically constant, fast right hander. It is not a throttle induced oversteer. The oversteer gets real stupid, real fast.I have not driven it on track with the factory 245 17 front and 275 18 in the rear. But would assume it would be a bit snug in the front. Maybe disconnecting the rear sway bar would balance the car a little more.

It's the oversteer part that I'm not to fond of, especially real stupid, real fast oversteer.

Various references state engineers induce "safety related" understeer within the Vettes to minimize spinning out (becoming dynamically unstable). It's not that I don't want the understeer, its that I want to increase the frictional boundaries to the maximum without inducing oversteer conditions. Whats too wide of a contact patch, or is it simply keeping the front contact patch just slighter more narrow than the rears - will that bring the car to a more neutral state w/o inducing stupid fast oversteer?

Various classes limit the amount of vehicle changes - i.e. adjustable shocks & coil-overs which places one in a race-prep / modified category. My car is surely no where near that, nor is the driver...

dale68z's mention of the oversteer at the sweeper Bondo West is a little confusing, EVERY car that exits that right hander at speed experiences wild oversteer! my favorite corner of all our local tracks.

try messing with your camber/toe settings. costs you nothing and makes a huge difference.

Camber - 2.5* up front and 1* in back

Toe - 1/8" OUT in front and 1/8" IN in back

if you have never done this before, ask for help!!

also, it is possible to help the car turn using the brakes and/or throttle... the driver mod is FREE!

Brake Oversteer pic attached - Also Bond West

I take it these alignment settings are for the staggered set-up and will help induce neutrality in the handling on street tires, or are these settings for some super sticky barely legal DOT tires? Also do you mean negative 2.5* camber up front & positive 1* camber outback? The placement of the "-" has me a bit confused.

I know at INDE Slammer taught me quite well that "driving the car" and using the throttle does INDEED help to steer the car where I want it to go, much better than I had thought.

It seems from the inputs that 18's all around or 17's all around (depending on what's available) with a slightly smaller front tire would be the better option...?

Link to comment
Share on other sites

I think going square is more a tire rotation and purchase issue, there are way to many varibles involved to say putting smaller tires on the rear will cure oversteer.

If you really want to control it, move weight forward, having a 50/50 balanced rearwheel drive with plenty oh HP will make the rear happy.

Try this, go into a sweeper faster than normal, but don't touch the brakes or throttle, sure your going to slide but it will be very controllable with no braking or acceleration forces to throw off the balance of a stock setup.

So now you want to power out of that corner, less weight on the rear will do 2 things, limit your input and if it does start to oversteer there will be less of a pendulum affect.

Now that you have more weight on the nose and you can power out of any corner with no stupid drift effect but your understeering more, then play with tire pressures.

p.s. I can also help with your holiday shopping at Jared's...

I just lost 40lbs so know you are telling me to get fat again to shift the weight forward? Holy hell, I think we better stick to shopping at Jareds. I don't know what smaller tires on the rear would do? That would certainly induce more oversteer don't you think or did you mean something else?

if you put 18's all around, aren't you putting a smaller tire on the rear?

.

Link to comment
Share on other sites

I think going square is more a tire rotation and purchase issue, there are way to many varibles involved to say putting smaller tires on the rear will cure oversteer.

If you really want to control it, move weight forward, having a 50/50 balanced rearwheel drive with plenty oh HP will make the rear happy.

Try this, go into a sweeper faster than normal, but don't touch the brakes or throttle, sure your going to slide but it will be very controllable with no braking or acceleration forces to throw off the balance of a stock setup.

So now you want to power out of that corner, less weight on the rear will do 2 things, limit your input and if it does start to oversteer there will be less of a pendulum affect.

Now that you have more weight on the nose and you can power out of any corner with no stupid drift effect but your understeering more, then play with tire pressures.

p.s. I can also help with your holiday shopping at Jared's...

I just lost 40lbs so know you are telling me to get fat again to shift the weight forward? Holy hell, I think we better stick to shopping at Jareds. I don't know what smaller tires on the rear would do? That would certainly induce more oversteer don't you think or did you mean something else?

if you put 18's all around, aren't you putting a smaller tire on the rear?

.

Not if you're a C5...

Link to comment
Share on other sites

I take it these alignment settings are for the staggered set-up and will help induce neutrality in the handling on street tires, or are these settings for some super sticky barely legal DOT tires? Also do you mean negative 2.5* camber up front & positive 1* camber outback? The placement of the "-" has me a bit confused.

I know at INDE Slammer taught me quite well that "driving the car" and using the throttle does INDEED help to steer the car where I want it to go, much better than I had thought.

It seems from the inputs that 18's all around or 17's all around (depending on what's available) with a slightly smaller front tire would be the better option...?

These alignments are a good starting place for any tire set-up. They are not absolute, but they are way better than factory... try new things making small adjustments, and see what is comfortable/fast for you.

Camber is negative, I cannot imagine a need for positive camber, ever. sorry, I see how my format was confusing.

I use 17s all the way around because the tires are less expensive, not because of any performance differences.

Link to comment
Share on other sites

I have driven my wife's 04 on track with 275 40 17's on all 4. I found the car well balanced with a hint of oversteer. This was on bondo west, scooting around the paddock, a basically constant, fast right hander. It is not a throttle induced oversteer. The oversteer gets real stupid, real fast.I have not driven it on track with the factory 245 17 front and 275 18 in the rear. But would assume it would be a bit snug in the front. Maybe disconnecting the rear sway bar would balance the car a little more.

It's the oversteer part that I'm not to fond of, especially real stupid, real fast oversteer.

Various references state engineers induce "safety related" understeer within the Vettes to minimize spinning out (becoming dynamically unstable). It's not that I don't want the understeer, its that I want to increase the frictional boundaries to the maximum without inducing oversteer conditions. Whats too wide of a contact patch, or is it simply keeping the front contact patch just slighter more narrow than the rears - will that bring the car to a more neutral state w/o inducing stupid fast oversteer?

Various classes limit the amount of vehicle changes - i.e. adjustable shocks & coil-overs which places one in a race-prep / modified category. My car is surely no where near that, nor is the driver...

dale68z's mention of the oversteer at the sweeper Bondo West is a little confusing, EVERY car that exits that right hander at speed experiences wild oversteer! my favorite corner of all our local tracks.

try messing with your camber/toe settings. costs you nothing and makes a huge difference.

Camber - 2.5* up front and 1* in back

Toe - 1/8" OUT in front and 1/8" IN in back

if you have never done this before, ask for help!!

also, it is possible to help the car turn using the brakes and/or throttle... the driver mod is FREE!

Brake Oversteer pic attached - Also Bond West

i second that motion. you could also try different type tires front to rear, maybe a slightly more sticky aggressive tire in front, but definitely play with the alignment either way.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...