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In stock form, ITR is dead neutral at WOT in any gear - for example -- can accelerate at WOT in 2nd gear around a constant radius turn with no steering input.

Now that I have 'improved' the car by lowering it 15 mm (on stock springs via Koni Sports), adding bigger rear bar and 15x7 rims (1" wider and +5 offset rel. stock), the thing pushes like mad on the gas in turns - have to dial in aggressive steering against the throttle to maintain line.

Just swapping back to stock rims eliminates about 80% of the push problem. Is this some kind of torque-steer effect from increased scrub radius or what - maybe something to do w/LSD ?

Has anyone else ever experienced something similar ?

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01 NBP ITR
88 Blue Civic DX Hatch
02 GPW S2000

Maybe you get increased rear grip with the larger rims/tire that leads to understeer?? Changing the ride height will effect the scrub radius also won't it?

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Silver Honda
Green Ford
Blue/White Suzuki
Red Triumph
Grey BMW

"Never let life be shaped by fear of its end"

No, you're a towel!

What kind of tires are we talking about? Streets or Stickies?

Lowering the car 15mm (nearly 5/8") will certainly change the handling characteristics. Do you have adjustable length endlinks up front? I bet you're getting preload on the front bar causing a binding situation, and shooting the effective rate through the roof. You'll want adjustable links to get the bar with zero preload, so it can progressively load and allow the car to take a 'set' like it used to.

The wider wheel with the same tire is changing the shape of the contact patch, which even with the bigger bar, may be increasing rear end grip.

With my STS Celica, I ran a 22mm rear bar and a 17mm front bar, both adjustable. (stock front was 23mm and the rear was about 14mm) On concrete I ran the mid setting up front and the full stiff in the rear. On asphalt, I would go full soft up front. Granted, my car had DA shocks all around with 375# linear Eibachs on coilovers up front with 900# linear Eibachs in the rear, so I could make the car do about anything I wanted. - AB

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'14 Toyota Sequoia Platinum 4WD
Super Westerfield Bros - '93 Integra - LeChump Du Jour
STX 93 - Scion FR-S

I haven't driven an ITR, but I had no idea that it worked that well stock. I can't imagine being able to run WOT in second in my Civic without the front eventually loosing traction because I am asking the front tires to do too much by accelerating and turning at the same time and eventually having the car push out. I guess it just depends upon what the radius is of this theoretical turn is? At some point the turn is tight enough that it can’t just act as you say. Is this for example maybe something like an onramp you are talking about? While it is now pushing, are you actually able to go faster than when it was stock?

Anyhow, I am not a suspension tuning expert (Aaron would know much more than me), but overall it seems like you changed a lot of things at once and the car SHOULD be handling differently. The things that you did sound like they should have helped, but they have apparently changed the balance of the car in a way you don’t like. You mention that the car pushes and that moving back to the stock wheels seem to help. You don’t mention what tires and sizes you have mounted on the new and stock wheels.

I am somewhat at a loss, but one thing that you might think about is that it may be pushing not due to a loss of grip on the front, but maybe it increased grip in the rear relative to the front (basically same comment as Marcus). You also mentioned that you have a larger rear bar. Is it adjustable? For example, could it be on the “soft” setting that might actually be softer than the stock bar? This could be transferring some grip that would have been at the front previously to the rear.

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Richard Casto
1972 Porsche 914
2013 Honda Fit Sport
2015 Honda Fit EX
http://motorsport.zyyz.com
Money can't buy happiness, but somehow it's more comfortable to cry in a Porsche than a Kia.

15x7's have 205/50-15 RT615's and stock rims (15x6) have 195/50-15 Bridgestone S-03. Not 100% apples/apples on tires - S-03's have shorter and significantly stiffer sidewall.

Neither sway bar is adjustable. Note that turn-in is pretty good (little/no understeer), getting plenty of lift-throttle rotation (can get more or less than stock depending on rear tire pressure) and have good transitional response. So car is quite well balanced everywhere except when getting on the gas - and it's not just a slight push - it's as if front tires are on ice (w/15x7's) using anything more than 30% throttle.

The WOT neutrality comment was referring to a relatively large radius situation where I start the WOT well below the limit and the car 4-wheel drifts as limit is reached.

I have tried shock, tire pressure, alignment tuning and loosening front bar all with limited / no impact compared with the wheel swap effect.

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01 NBP ITR
88 Blue Civic DX Hatch
02 GPW S2000

Out of curiosity, which scenario has the higher speed (using the same radius turn)?

* Stock (point at which you have steady state four wheel drift and can't accel anymore)

* Modified (point at which the front starts to push and you can't accel anymore).

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Richard Casto
1972 Porsche 914
2013 Honda Fit Sport
2015 Honda Fit EX
http://motorsport.zyyz.com
Money can't buy happiness, but somehow it's more comfortable to cry in a Porsche than a Kia.

Sorry I neglected to answer that part of your question earlier...

The modified setup (push and all) results in slightly higher ultimate grip (or speed, on the same turn) compared with stock car on the same RT-615's. Difference is pretty small however (<5%).

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01 NBP ITR
88 Blue Civic DX Hatch
02 GPW S2000

Did you have the car Alinged after you lowered it? I know its just a little but it could have change your toe and camber settings front and rear. More rear Camber and toe in and the car will not rotate as easy.

I have never driver an ITR either however on my del sol when I had it lowered with 275f and 400 r springs I could also not expect the car to not push at WOT.

The other thing could be you are probably going faster and could be reaching the limits of traction on the front of the car so it is washing out, also you could be over driving since you feel like it should be faster with the new suspension, just a thought.

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David Teague
2015 Lexus IS 250c
1994 Honda Del Sol HS 39
2009 Dodge Journey R/T
http://teaguefamily.us

You're stating that you're basically accellerating around the equivalent of a skidpad and that the radius isn't changing???

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Has no responsibility whatsoever.

I had it aligned after lowering - similar toe numbers before and after and gained camber (more in front than rear). The weird thing about this is turn-in, lift-throttle, trail-brake and transition balance are all just like stock (which is to say very good) while the on-gas phase is way out of whack compared with stock. I am sure the rims are responsible - guess I just want to figure out why...



Yes - I have a remote, constant radius ramp where I can do fairly repeatable testing, so I know exactly how on-gas and lift-throttle behavior has changed with each modification.

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01 NBP ITR
88 Blue Civic DX Hatch
02 GPW S2000

Sorry, but testing on the street is DUMB.

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02 Focus SVT
STF 9

Are you taking the recent fall in temps into consideration? Just asking because cold tires/pavement will cause what you're describing

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In need of car.

Yeah, if you're changing stuff and testing, you should be playing around in a deserted parking lot (or a field, in certain cases). Streets and "remote, constant radius ramps" aren't wide enough to really test stuff.

The one coming off Western to South Saunders is...

Just kiddin'