Car feels strange/less responsive after coilovers

[steverife]

I know track days are a little different, but for autox…


Even at stock power, there are huge benefits going to a 245 on a 17x9 wheel. I can't really imagine any performance scenario where you wouldn't want at least a 245 wide wheel at any power level.

[Racecomp Engineering]

Originally Posted by Milhouse86

How much HP was your shop car putting out? Is there certain power levels? Areo levels? Or what to justify wider wheels?

Better question may be...What am I really looking for the car to feel like, to know whether a wider would be beneficial or detrimental?

Sorry new to track days. I have some Tarmec 2's sitting on my shelf waiting to go in this winter. I plan to keep running stock wheels with Hankook RS4 225 for now but after FI I was thinking 17x9. I liked what I have read on the Maxxis VR1 and was thinking probably in a 255 after the SC. (Built engine with 10.1 this winter) I'm going to lose a few horse by staying naturally aspirated this summer but I need to work on my line more than anything anyway.

Sorry to hijack but I though the similar question could help OP.

Sent from my Pixel 2 XL using Tapatalk

It was still NA but had most things done (headers, tune, shorter final drive, etc). More power and overall level of prep does make wider wheels/tires more useful. More driver experience is also a big one.

Your plan for 225s now, 255s later with FI is good. Get some experience and skills as is and you'll be more ready when the time comes in the future.

- Andrew

[NoHaveMSG]

Originally Posted by steverife

I know track days are a little different, but for autox…


Even at stock power, there are huge benefits going to a 245 on a 17x9 wheel. I can't really imagine any performance scenario where you wouldn't want at least a 245 wide wheel at any power level.

Sometimes it is hard to get the car to do what you want at speed with the wider tire. Like if I need the car to rotate a bit mid corner. The car feels more lively and responsive to inputs. I don't feel traction limited. There is also the the weight/drag factor which is not as severe as people make it out to be, but it is noticeable.

If you check out rice_classics thread on his SCCA T4 car, they came to a similar conclusion.

[steverife]

Originally Posted by NoHaveMSG

Sometimes it is hard to get the car to do what you want at speed with the wider tire. Like if I need the car to rotate a bit mid corner. The car feels more lively and responsive to inputs. I don't feel traction limited. There is also the the weight/drag factor which is not as severe as people make it out to be, but it is noticeable.

If you check out rice_classics thread on his SCCA T4 car, they came to a similar conclusion.

From what I understand, the T4 car is on Hoosiers (or comparable R-comps) on a 7" wide wheel. When rule limited by wheel size, sometimes you can get better feel and balance running a tire that fits the wheel a little better. I totally agree in that context. Running stock classes in autocross that require stock width wheels, I've beaten competitors that were running wider wheels.

In the context of street tires and the freedom to run an appropriate wheel (say a 17x9), the 245's will pay dividends, even on stock power.

[NoHaveMSG]

Originally Posted by steverife

From what I understand, the T4 car is on Hoosiers (or comparable R-comps) on a 7" wide wheel. When rule limited by wheel size, sometimes you can get better feel and balance running a tire that fits the wheel a little better. I totally agree in that context. Running stock classes in autocross that require stock width wheels, I've beaten competitors that were running wider wheels.

In the context of street tires and the freedom to run an appropriate wheel (say a 17x9), the 245's will pay dividends, even on stock power.

Stepping down in width worked better for me so I dunno.

[strat61caster]

Originally Posted by steverife

I know track days are a little different, but for autox…


Even at stock power, there are huge benefits going to a 245 on a 17x9 wheel. I can't really imagine any performance scenario where you wouldn't want at least a 245 wide wheel at any power level.

A scenario where your lap time hinges on being foot to the floor for >1 minute and you're turning for <30 seconds.

The 949 car was on 255s iirc.

[wparsons]

Originally Posted by steverife

I know track days are a little different, but for autox…


Even at stock power, there are huge benefits going to a 245 on a 17x9 wheel. I can't really imagine any performance scenario where you wouldn't want at least a 245 wide wheel at any power level.

CSG did a ton of testing, and found that on most tracks a 225 is faster than a 245 on stockish power (not FI).


Autox is very different because speeds are lower and you spend way more time (as a percentage of run time) cornering and way less time WOT in a straightaway.

[CSG Mike]

Originally Posted by wparsons

CSG did a ton of testing, and found that on most tracks a 225 is faster than a 245 on stockish power (not FI).


Autox is very different because speeds are lower and you spend way more time (as a percentage of run time) cornering and way less time WOT in a straightaway.

Just to clarify for a lot of folks, this is ***COMPLETELY*** track and driver dependent. It 1. depends on the driver to maximize the grip of a lesser tire, and 2. it strives to find the balance between cornering speed and straight line speed. To a lesser degree, it is vehicle setup dependent.

The average driver will usually find more value in a larger tire giving them more thermal capacity, rather than seeking the theoretical "fastest" setup that they may not be able to fully exploit.

[new2subaru]

FWIW, I've been running 205 RS3's on track for the last couple of years. They run as wide as stock 215's and because of the narrow width have taught me a lot about car control.


Narrow tires = fun

[mrhayes1]

There could be many suspension issues; I have no idea on that. I can tell you that what you are experiencing is likely a direct result of going with a much wider tire. I run 245s and noticed a difference so your will feel even worse. Its what happens when you run wide wheel/tires. Running a different tire probably wont even help you because 4s should already be pretty stiff high performance tire.

[csol]

Taking it to the shop tomorrow will update you guys

[86MLR]

Something to read > https://mcasuspension.com/technical

[Spacemane969]

I had these exact symptoms after lowering and changing to a lighter 17x7.5 wheel so I would not count on wider wheels being a factor. The hard truth that I have learned about this platform is that because it is so finely tuned from the factory, it becomes very clear that handling won't get much better once you start tweaking even the most minor things. You have so much room to screw things up and very little of not zero room for improvement.

[strat61caster]

Originally Posted by Spacemane969

it becomes very clear that handling won't get much better once you start tweaking even the most minor things. You have so much room to screw things up and very little of not zero room for improvement.

You have clearly not experimented with camber yet.