Ap1 Understeer
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Joined: Apr 2023
Posts: 32
Likes: 10
From: Long Island, NY
AP1's are notorious for oversteer and most run big front bars to battle it. Even the most experienced autocrossers I know spun or nearly spun my AP1 on their first run in it when I was running it street classing. Those coilovers would not be my first choice at all but I do not think they are causing the car to be pushy like that.
I would first focus on your inputs, as you are seeing behavior not typical of this car. If on lower speed corners, focus on your braking points (are you abruptly dumping off the brakes well before turn in, causing the front to get light?), and power point (are you mashing the accelerator too early and the resulting rearward weight transfer is causing the fronts to get light?), are you overdriving the entry to the corner, how smoothly you are turning in (are you turning too fast and too far, causing the fronts to lose traction?). On that latter one, when you feel the understeer happening, start straightening the wheel slowly until the fronts bite again.
Now, 200 TW tires are going to be what you want to be competitive. I am not sure what you are running now.
Does it for sure have a stock front sway bar or an aftermarket bar?
Also, you need to let us know what class you are targeting. You are already in STR with those shocks, is that where you want to stay? You cannot run AP2 wheels on an AP1 in C Street but if sticking with those coilovers you are in STR anyways, but good to know your intentions there.
I would first focus on your inputs, as you are seeing behavior not typical of this car. If on lower speed corners, focus on your braking points (are you abruptly dumping off the brakes well before turn in, causing the front to get light?), and power point (are you mashing the accelerator too early and the resulting rearward weight transfer is causing the fronts to get light?), are you overdriving the entry to the corner, how smoothly you are turning in (are you turning too fast and too far, causing the fronts to lose traction?). On that latter one, when you feel the understeer happening, start straightening the wheel slowly until the fronts bite again.
Now, 200 TW tires are going to be what you want to be competitive. I am not sure what you are running now.
Does it for sure have a stock front sway bar or an aftermarket bar?
Also, you need to let us know what class you are targeting. You are already in STR with those shocks, is that where you want to stay? You cannot run AP2 wheels on an AP1 in C Street but if sticking with those coilovers you are in STR anyways, but good to know your intentions there.
The class I’m would like to target is C street. Glad to know what I cannot run AP2 wheels in c class. As for the coil overs I don’t want to splurge money on new ones. I would prefer to learn the car first and go from there. I would preferred the car to be on the oversteer side.
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Joined: Jul 2005
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From: Michigan
I have Continental Extreme Contact DWS 06+ for the rears with production date of 23/22.
For the fronts I have Good year eagle sports with a production date of 04/20 (damn that’s some old tires, maybe this is the reason why I’m understeering?)
My pressures before was 30Psi all around and after the runs it climbed up to 32-33psi. But I dropped it down to 30psi.
For the fronts I have Good year eagle sports with a production date of 04/20 (damn that’s some old tires, maybe this is the reason why I’m understeering?)
My pressures before was 30Psi all around and after the runs it climbed up to 32-33psi. But I dropped it down to 30psi.
Get a new set of tires (that match) and are summer performance tires.
Joined: Jul 2014
Posts: 13,906
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From: Chesterfield VA
Like Sam wrote. Get a new set of tires (that match) and are Extreme Performance Summer tires. Run stock tire sizes this season and wear them out just learning handling and driving. Next season decide if a "square" setup makes sense. Square = Oversteer^2 since the S2000 oversteers more than what most folks are used to. Any form of racing is a money pit. Don't dig a hole you can't get out of.
-- Chuck
-- Chuck
Joined: Apr 2017
Posts: 441
Likes: 82
From what I found online site that the previous owner brought from the spring rates are 560 Lbs (10Kg) for the fronts and 175 Lbs
(3 kg) for the rears.
I would like to go squared setup, but what tires should I be running? I would like to keep the car as stock as possible. I’m open to flaring my fenders if I gotta buy 2 sets of s2k wheels
(3 kg) for the rears.
I would like to go squared setup, but what tires should I be running? I would like to keep the car as stock as possible. I’m open to flaring my fenders if I gotta buy 2 sets of s2k wheels
10/3k spring rate bias would be a terrible match even for nonstagger cars. If it's the Tein Flex Zs you have then other sites say they are 10/10k which is more reasonable. If it's truly 10/3k then that's likely part 1 of your problem. You have way too much front roll stiffness on a staggered car. Part 2 is that you have mismatched tires. Don't have experience with the good years but I have driven on the Conti's which are decent. Regardless if you have a rear grip mismatch that's the other reason you're understeering. Part 3 as others have mentioned is your alignment and who know where it is right now.
I'd start out getting new tires and alignment. I wouldn't worry about going nonstagger just yet, that was probably bad advice of me to mention it since it would introduce even more variables. Get a good proper baseline of your car first before changing anything else. Understand your car and what it does so you can make an educated decision on what to do next. The car is very capable even in stock trim. Unless you're at nats and at the pointy end of the pack it's all driver mods. I have a very fast local in a stock AP1 that can match local ND2s with driver mod.
Thread Starter
Registered User
Joined: Apr 2023
Posts: 32
Likes: 10
From: Long Island, NY
10/3k spring rate bias would be a terrible match even for nonstagger cars. If it's the Tein Flex Zs you have then other sites say they are 10/10k which is more reasonable. If it's truly 10/3k then that's likely part 1 of your problem. You have way too much front roll stiffness on a staggered car. Part 2 is that you have mismatched tires. Don't have experience with the good years but I have driven on the Conti's which are decent. Regardless if you have a rear grip mismatch that's the other reason you're understeering. Part 3 as others have mentioned is your alignment and who know where it is right now.
I'd start out getting new tires and alignment. I wouldn't worry about going nonstagger just yet, that was probably bad advice of me to mention it since it would introduce even more variables. Get a good proper baseline of your car first before changing anything else. Understand your car and what it does so you can make an educated decision on what to do next. The car is very capable even in stock trim. Unless you're at nats and at the pointy end of the pack it's all driver mods. I have a very fast local in a stock AP1 that can match local ND2s with driver mod.
I'd start out getting new tires and alignment. I wouldn't worry about going nonstagger just yet, that was probably bad advice of me to mention it since it would introduce even more variables. Get a good proper baseline of your car first before changing anything else. Understand your car and what it does so you can make an educated decision on what to do next. The car is very capable even in stock trim. Unless you're at nats and at the pointy end of the pack it's all driver mods. I have a very fast local in a stock AP1 that can match local ND2s with driver mod.
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Joined: Jun 2023
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im pretty sure i have a stock sway bars, damn now you got me thinking m. Gonna try and jack up the car and see what I have.
The class I’m would like to target is C street. Glad to know what I cannot run AP2 wheels in c class. As for the coil overs I don’t want to splurge money on new ones. I would prefer to learn the car first and go from there. I would preferred the car to be on the oversteer side.
The class I’m would like to target is C street. Glad to know what I cannot run AP2 wheels in c class. As for the coil overs I don’t want to splurge money on new ones. I would prefer to learn the car first and go from there. I would preferred the car to be on the oversteer side.
Registered User
Joined: Jul 2020
Posts: 425
Likes: 87
From: Massachusetts
Hey everyone,
Just wanted to share my excitement after attending my first autocross event with my 2001 S2000. It was an absolute blast, and I can definitely see myself going again!
However, I did encounter some understeer issues, especially through slower corners.
Currently, I’m running on stock 16-inch wheels with 205/55R16 on the fronts and 225/50R16 on the rears. My suspension setup consists of Tien Flex Z, which came with the car when I purchased it, and everything else is stock.
I’m wondering what I can do to reduce the understeer. Would switching to 200-300 TW tires help? I also have a spare Ap2V1 wheels at my disposal, wondering if going bigger wheels can help with that. Any advice or insights would be greatly appreciated!
Looking forward to hearing your thoughts. Thanks!
Just wanted to share my excitement after attending my first autocross event with my 2001 S2000. It was an absolute blast, and I can definitely see myself going again!
However, I did encounter some understeer issues, especially through slower corners.
Currently, I’m running on stock 16-inch wheels with 205/55R16 on the fronts and 225/50R16 on the rears. My suspension setup consists of Tien Flex Z, which came with the car when I purchased it, and everything else is stock.
I’m wondering what I can do to reduce the understeer. Would switching to 200-300 TW tires help? I also have a spare Ap2V1 wheels at my disposal, wondering if going bigger wheels can help with that. Any advice or insights would be greatly appreciated!
Looking forward to hearing your thoughts. Thanks!
For slow/sharp corners, it's easy to try to turn the wheel and expect grip beyond what the car is actually capable of. Setting up properly for these can help, that involves slowing enough and entering wide to backside the cone so you require less steering input for the turn.
Thread Starter
Registered User
Joined: Apr 2023
Posts: 32
Likes: 10
From: Long Island, NY
So after quite some time I pulled the trigger on some continental o2 for all 4 sides. And man the car does not understeer at all.
But on the other hand the rear wants to kick back whenever I’m mid corner. Now I can finally learn the car and dial it.
But on the other hand the rear wants to kick back whenever I’m mid corner. Now I can finally learn the car and dial it.
Thread Starter
Registered User
Joined: Apr 2023
Posts: 32
Likes: 10
From: Long Island, NY
So after quite some time I pulled the trigger on some continental o2 for all 4 sides. And man the car does not understeer at all.
But on the other hand the rear wants to kick back whenever I’m mid corner. Now I can finally learn the car and dial it.
But on the other hand the rear wants to kick back whenever I’m mid corner. Now I can finally learn the car and dial it.
