What do I need to change to fix my problem?

[UFO]

I've tracked various cars over the years: a 2003 Evo VIII, a 2005 Evo VIII, a 2001 Porsche 996 C4, and a 2008 Evo X. I was always faster than everyone else in my run group because, well, 300HP and AWD. I used to think I was a pretty good driver but now realise it's not hard to drive a fast car fast!

I've been driving a local track in the FR-S and next weekend will be my 5th time there. I've gone from a lap time of 2:15 to 2:06 and during that transition all I've changed is track time, brake fluid and pads. I'm mostly stock suspension, just have RCE yellow springs and crash bolts with -2.3 camber up front. Also running Enkei RPF-1s 17X9 +35 with 245/40 Hankook R-S3 V2 tyres.

There are at least 2 corners that I feel I could be flat through but the car pushes too much and I have to modulate the throttle. I feel that I need to change something suspension wise but I don't know what. I see so many suspension options but how do I know which option will fix my problems? Will going to coilovers help? Bushings? More camber? Other adjustable suspension components?

I realize this is an insanely ambiguous question but how do I know which suspension part will fix which issue I'm facing?

[swarb]

Play with tire pressures.
Try a different line.
Try different alignment settings. Less toe in rear, more toe out front. More camber up front may help or less in the rear, with a pyrometer it would give you some data.
Have someone more experience sit with you, or sit with someone with the same car.
Whatever you change to make it better, it might make it worse at another part of the course.
You could describe the turn or when/how you experience the issue.

[steve99]

If its understeering you could try a slightly stiffer rear sway bar.


hopefully you might be able to lend one and see, as it might cause you other issues.

[strat61caster]

My suggestion is more camber up front, in my experience the car was happier up at about -3 to -3.2 degrees camber on stock suspension than the -2.5 I started out with after getting camber plates, I'm even higher now but on autocross oriented coilovers.

imo changing other things and buying other parts doesn't make much sense if your tires aren't pointed in the optimal direction, you're just band-aiding the fact that you're not using all of the tire available. Getting tire temperatures will help point you in the right direction but it isn't foolproof and ultimately experimentation will get you where you need to go.

[nikitopo]

Originally Posted by UFO

I've tracked various cars over the years: a 2003 Evo VIII, a 2005 Evo VIII, a 2001 Porsche 996 C4, and a 2008 Evo X. I was always faster than everyone else in my run group because, well, 300HP and AWD. I used to think I was a pretty good driver but now realise it's not hard to drive a fast car fast!

Exactly, it is much easier to be fast on a powerful and more forgiving (AWD) car.

Originally Posted by UFO

There are at least 2 corners that I feel I could be flat through but the car pushes too much and I have to modulate the throttle. I feel that I need to change something suspension wise but I don't know what. I see so many suspension options but how do I know which option will fix my problems? Will going to coilovers help? Bushings? More camber? Other adjustable suspension components?

Coilovers will be very helpful to fine dial your car, but don't go on cheap options. Bushings are also very helpful and will give you a more linear suspension feel. The current setup is optimized more for the road.

[Sleepless]

These cars generally oversteer once in a corner so I'm guessing you might be entering the corners too slowly and the making up by accelerating to hard too soon. Try different lines (like double apexing large radius corners) and entering faster with trail braking.

[Twinz]

I recommend having a good instructor/ veteran drive / ride with you through these problem turns first.

Try to nail down if it's the car or the driver that needs to change before you spend a lot of money.

[ls1ac]

As above, 1) good instructor 2) tire pressure. Learn, experience, then change setting, and finally change parts.
These cars are very good out of the box, and can teach a lot about doing most every thing right. Good parts should make you faster but only the clock will tell the truth. Seat of the pants feel is often biased by how much you spent on parts. Change parts only after you think you know what each piece will do then verify it is doing what you thought it would. Changing many parts at once makes it very difficult to find what is doing what.

[redlined600]

Originally Posted by Twinz

I recommend having a good instructor/ veteran drive / ride with you through these problem turns first.

Try to nail down if it's the car or the driver that needs to change before you spend a lot of money.

THIS. The fact that you dropped 10 seconds on a 2 min course indicates there might be more out there. That doesn't mean you can't tune to your preference but the car might not be the limiting factor at this point.

Imo.
Start with the instructor
Add more front camber
Try a rear sway bar

From there one needs to be sure they have the ability to properly setup the car or have a good relationship with a good shop to set it up.

[solort]

Sounds like you may be entering corner too fast, overheating front tires, too much front tire pressure (should be pretty low with that wheel/tire combo and will go up quickly as tires heat up), too little front camber, or too much rear toe in....

I found my car better balanced with a larger 20mm front bar (adjustible Whiteline with adjustable end links to remove front bar pre load) and the stiffer bar minimized front camber loss by keeping car flatter in corners...

And turn off most nannies with either 6 sec traction control button press, or the all nannies off "pedal dance" so that the car handles as God intended...

[UFO]

Thank you everyone for the suggestions. I will have an instructor with me again this weekend, each time I go they want to bump me up but I would rather have the instructor in the car with me as I'm there to learn. I don't have a pyrometer but I do have one of those laser temperature readers which will have to suffice for the time being, I'm running 35ish PSI hot right now.

They're both pretty high speed corners, 90 MPH and 85 MPH mid-corner on each so I'm pretty sure that some of my issues are me. Confidence is building though!

[UFO]

Originally Posted by swarb

Play with tire pressures.
Try a different line.
Try different alignment settings. Less toe in rear, more toe out front. More camber up front may help or less in the rear, with a pyrometer it would give you some data.
Have someone more experience sit with you, or sit with someone with the same car.
Whatever you change to make it better, it might make it worse at another part of the course.
You could describe the turn or when/how you experience the issue.

Here you go. first corner

. First corner is a pretty big lift (no brakes) and mid corner my power steering goes completely dead for a split second and the steering gets super heavy. The car's not tracking out to the edge of the track by itself so I know I could carry more speed through. The only issue is on the gas at corner entry makes me feel like I'm going to be in the grass because the fronts don't turn in the same as they do off the gas. Second corner is the same, on the gas at turn in the car just doesn't want to turn but, again, I know I can carry more speed through the corner.

[swarb]

Originally Posted by UFO

Here you go. first corner

. First corner is a pretty big lift (no brakes) and mid corner my power steering goes completely dead for a split second and the steering gets super heavy. The car's not tracking out to the edge of the track by itself so I know I could carry more speed through. The only issue is on the gas at corner entry makes me feel like I'm going to be in the grass because the fronts don't turn in the same as they do off the gas. Second corner is the same, on the gas at turn in the car just doesn't want to turn but, again, I know I can carry more speed through the corner.

What turn numbers are they called in the video?
So I can look at the line you take before entering the corners.

Guess would be to add more camber in the front for more turn in grip(I see lots of people at -3 up front) and less rear toe in(or close to zero) for more rotation.
What are your alignment settings?
And an adjustable rear sway bar would also help with some rotation. This car does understeer with equal spring rates front and rear. Some people say the car is oversteer prone, but I disagree, they usually have harsh steering inputs and a heavy foot. The camber gain from macpherson strut isn't ideal under compression so the car needs a lot of camber up front.

[Ultramaroon]

Stock geometry is still way understeery. Like strat said, negative camber up front is your friend.

And get yourself a decent oil cooler.