Forgive me if I sound like a broken record on this problem, but I'm still trying to understand an on-gas push problem... Believe I may have discovered the problem - 15x7, +45 rims.

Has anyone else noticed an on-gas push tendency with wider rims / increased offset etc ???

 

I think this can be a number of different things. One of the main things I can think of is going to a wider tire compared to the stock tires. At least, on a stock sized wheel anyway. Not sure if a wider tire on a wider wheel will have the same effect as wider tire on the stock wheel. For instance going from the stock size to 205/50 Azenis sorta gives you that less than pinpoint turn-- in feeling. But I assume that could be related to the tire itself as well (sidewall, compound, etc).

What sort of alignment/camber settings do you have?

 

Setup = lowered 17 mm on stock springs (via relocated snap-rings on Koni Sports), 25 mm rear bar, -1.3 front camber, -1.0 rear camber. I have directly compared 195/50-15 S-03's on stock rims to 205/50-15 RT-615 on 15x7's.

There is very little noticable handling difference between these except for on-gas pushing. I can run WOT 2nd or 3rd gear with stock wheels with no push at all, while the 15x7's cause me to dial in steering quickly to maintain the line.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RTW DC2R &raquo;</TD></TR><TR><TD CLASS="quote">I think this can be a number of different things. One of the main things I can think of is going to a wider tire compared to the stock tires. At least, on a stock sized wheel anyway. Not sure if a wider tire on a wider wheel will have the same effect as wider tire on the stock wheel. For instance going from the stock size to 205/50 Azenis sorta gives you that less than pinpoint turn-- in feeling. But I assume that could be related to the tire itself as well (sidewall, compound, etc).

What sort of alignment/camber settings do you have?</TD></TR></TABLE>

That would be my guess. My Azenis sometimes try to go where ever they wanna go.

 

The scrub radius is definately changed, which is why on lower # offset wheels (also increasing the width) the car tends to follow grooves and tracks in the road. What you're describing I've never heard of, but then again the stock spring rates are rather soft to begin with and you lowered the car on them. Basically the stock suspension setup is very finely tuned, and though certainly not perfect I wouldnt doubt its ability to outhandle another R with just a Koni Sport drop and stock springs...

BTW I notice an incredible difference between the stock 15x6" +50 on 195-55-15, and 15x7" +38~44, theres a big difference in just swapping those setups right there.

 

Torque steer and understeer (on-gas push) are not the same thing (correct me if I'm wrong).

Lower offset wheels will reduce understeer (wider track) but increase torque steer (larger scrub radius).

 

In general, I would say that's right. In fact, I do not have any 'typical' straight-line torque-steer problems with either setup - this is strictly a cornering issue.

Maybe it's not actually torque-steer, but I do know the rims/tires are the issue. The S-03's have a very stiff sidewall compared with RT-615 (and shorter sidewall at 195/50)... Guess that could be the issue...

 

I definitely get more torque steer on the 16" JDMs that I did on the 15" stockers. But the understeer is about the same (i.e. not much, unless you're driving lame :-) )

 

By torque-steer, do you mean in a straight line ?

So no push on the gas hard in a corner ?