Hi all,

Just wondering if you could help??? Anyone..
From buying my MY00 around 2 years ago, I have always noticed when I accelerate hard the car had a tendency to feel vague through the wheel.
I tried changing springs (-30mm) with a full setup and all new tyres. Improve problem but still an issue.
Noticed the rear roll bar links where broken, so replaced those. A slight improvement again.
Other than a pair of drive shaft spacers the car is standard, with standard wheels. Rear Tyres are now 245s though...another failed attempt in problem solving.

I would like to check:
A) Torque sensor calibration.
B) Steering rack pre-load.

Tried looping the pins on the OBD but to no avail. As far as rack pre-load too, hum?? Honda dealer just gave me a blank look and said they can't be done on my model year??

I do have good mechanical knowledge, but everything I have checked looks great.

Just for reference when doing any speeds over 110mph (not on public roads) the car feels very very unstable.
When it rains sometimes have problems doing over 60mph because the car aquaplanes very badly, tried x5 sets of tyres over 2 years, still no improvement.
In the winter it is obviously pretty un driveable. The LSD locks the both back wheels when not on the accelerator, etc etc.

Having owned s Sierra Cosworth previously for 7years some of these traits I can deal with, some are a step backwards.. I am certain my s2000 should be awesome in handling terms when compared to my Cossie.

Ok back to subject. Some more descriptions.
1.When looking at the wheels, the slightest movement in the steering wheel does seem to have a direct effect on wheel movement.
2.When you drive the car it feels as if you can steer it a little through the throttle. I.e, accelerate pulls right, lift off pull left. Very minor...
3.In a corner, both right and left, accelerate and the car runs wide, lift off and it turns in aggesively. Yeah of course when you press hard it will oversteer and is very simple to control and maintain a drift but when not driving hard slight imputs can make the car dive into corners.

Next Steps I'm considering..

Changing wheels soon.
Change Track rod ends.
Lower splitter to improve air flow.
Spoiler.
Diffuser.
Improved Chassis Bracing Front & rear.
Steering rack spacers.
Anti-bump steer kits.
Roll Centre adjusters.
POLY bush kit.
New Steering rack.

My worry is the cost of all of this... eeekk.


ANYONE ELSE HAD THIS PROBLEM? HOW DID YOU REPAIR IT?
Regards,
Andrew.

 

This does not sound normal to me, you might want to change your diff oil and send a sample in for analysis.

 

Start simple...

What are your alignment settings?

 

Changed Didd oil last month, replaced with the genuine Honda MTF gear oil. Still the same. Diff quiet and works well. When it breaks traction both wheels spin up. The only transmission noise I have is the dreaded clutch buzz (soon to be resolved).


Current Alignment =

Total toe - -0°03'

Front Left;
Camber -0°03'
Toe- -0°03'

Front Right (drivers side, uk model MY00);
Camber -0°03'
Toe - 0°00'

Rear Left;
Camber -1°36'
Toe 0°24'

Rear Right;
Camber -1°24'
Toe 0°24'

Castor - Not measured.
Thrust angle -0

Highlight any majors, I rely that my local algnment specialists aren't pulling a fast one.

Cheers Again,
Andrew

 

I mean the LSD locks both wheels under engine breaking. I am not actually concerned about this, its usually only in rain and snow.
Similar to what my motorbike does, when the weight is transferred to the front wheels or in very slippery conditions.

 

That is .8 degrees of total rear toe in. I'm guessing this is heavily contributing to the instability of your car. Each rear tire is trying to swing the rear end around. If both tires have the same grip, they are fighting each other and cancelling each other out. If one tire gains a grip advantage over the other - road surface change, ridge in the road, etc. - the result will be rear steer. At speed this would be a very uncomfortable feeling.

I suggest you back the rear toe down to 0.1 degrees (6 arcminutes) toe in per side, so about 0.2 degrees (12 arcminutes) total rear toe in. This will give you a much more stable feel to the rear end when traveling in a straight line without causing instability when turning.

 

That is .8 degrees of total rear toe in. I'm guessing this is heavily contributing to the instability of your car. Each rear tire is trying to swing the rear end around. If both tires have the same grip, they are fighting each other and cancelling each other out. If one tire gains a grip advantage over the other - road surface change, ridge in the road, etc. - the result will be rear steer. At speed this would be a very uncomfortable feeling.

I suggest you back the rear toe down to 0.1 degrees (6 arcminutes) toe in per side, so about 0.2 degrees (12 arcminutes) total rear toe in. This will give you a much more stable feel to the rear end when traveling in a straight line without causing instability when turning.
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Thanks for the advice. This sounds like it make sense. I wonder what the actual Honda spec is for toe?
Bang on about the uncomfortable feeling- I really start getting worried.

Think i'll get it booked in for a re-alignment.

Any other ideas would be cool too?

 

I believe the Honda spec is 0.16 to 0.32 degrees of rear toe in per side. In my experience, Honda specs too much rear toe in.

 

To some extent, this is normal. The EPS isn't known for giving a lot of feedback, and when you accelerate you unload the fronts, which could give the sensation of further reduction in feel.

If you have 245s on AP1 rims (other than R-compound track tires), you are *guaranteed* to have subpar tires as far as performance goes. So what tires (make and specific model) are you running? This is HUGE. A great stereo will sound like crap through $10 speakers, a great sports car won't handle well on crap tires.

What you're describing is exactly how the car will act with excessive rear toe-in. Too much toe on the AP1 in particular makes for a VERY evil-handling car. You want ~.2-.3 degrees total rear toe (.1 - .15degrees per side).
Any more than that and the car will start to handle non-linearly and become more twitchy/unstable, AND you'll get accelerated tire wear AND worse mileage. Too much rear toe SUCKS, for EVERYthing.

Check rear tire pressures. Also, one rear could be bad (internal defect). Given that you're on subpar tires (if 245s on AP1 16" wheels), you might consider new tires anyway...

This is how cars are SUPPOSED to behave. Perfectly normal handling characteristics for a responsive car. Unfortunately 99.9% of drivers don't realize this because almost all cars are "tuned" to understeer, always.

Regarding power ON oversteer, that only really happens with a stock s2k in first gear. Otherwise, not nearly enough torque at the rear wheels to get this. Generally, power ON => UNDERSTEER. Power OFF (or stab of the brakes) => OVERSTEER.

Regarding slight inputs making the car dive intor corners, PERFECTLY NORMAL for a sports car. Any sports car that DOESN'T behave this way has had the responsiveness tuned out of it.
This is handling dynamics 101, very basic stuff.

Long/short: It ain't the car. Other than the minor pull you mention(which points to tires), the car is behaving NORMALLY. Possible that crap tires playing a contributing role, but you should EXPECT oversteer when you get off the throttle and understeer on the throttle.

A proper alignment with *minimal* rear toe will help with twitchiness and driveability in the rain and over bumps/undulations. For street, something like:
-1deg front camber
0 front toe
-2deg rear camber
0.2 - 0.3 degrees total rear toe (.087" - .131" total)

 

I think this is the 1st port of call. I wouldn't care I bought all new camber and toe bolts (from dealer - ouch) and they ended up managing to free the originals up completly to do the last setup.

Thanks man!!