Handling characteristics with a low offset and narrow wheel width

[surfwaxsmitty]

Some related threads I have read:
16” wheel thread http://www.ft86club.com/forums/showthread.php?t=27023
Effect of wheel offset http://www.ft86club.com/forums/showthread.php?t=69190

In addition to this, various posts discussing wheels such as the kosei 17x8 +36mm and other similar setups, have mentioned the changes in handling that to me sound undesirable.

The closest comments I have read with first hand experience of 7 in wide +35 wheel came from this thread http://www.ft86club.com/forums/showthread.php?p=2692902
Quoted: “I was going for a more flush look than stock with as little change to OEM wheel spec as possible. My theory was that the stock wheel width would provide a similar feel but I didn't account for the fairly moderate/aggressive offset on these wheels. To be honest it feels like I kind of ripped the soul out of the car...steering is very numb with much less feedback and the steering wheel travel "feels" a lot looser now...giving a kind of balloonish feeling when taking even the slightest turns. To be honest I don't have a lot of confidence right now, it feels like one bad move could put me into a tree."


So, when people run 17x9 +35 it seems all is well? I understand that the 2 additional inches (~51-52mm) is distributed half inner side and half outer side, and when paired with +35 (13mm lower than stock) the wheel would have additional 39mm beyond the hub and an additional 13mm on the inner side of the hub.

Comparing this with 7 inches wide and +35 it is simply shifting the wheel outward with an additional 13mm outer side of the hub, and 13mm reduced on the inner side of the hub. How different is this?

How much should I be concerned about the handling changes with a 16x7 +35? Will it be nearly the same as the experience had by the guy with 17x7 +35 referenced above?

My reasoning for considering 16x7 +35 is that the RPF1 is the only lightweight and affordable new option available. I just moved to New Orleans, and for anyone familiar with roads down here, its just crazy how chopped the surfaces are and the amount of potholes. I also would enjoy having a 35lb wheel tire combo. The only other 16x7 wheel option I’m considering that isn’t also a +35 offset is the rota slipstream 16x7 +40, but damn near refuse the black wheel form black car, and would be happier with an enkei wheel. Is the +40 worth it?? Just have to paint em lol

If I didn’t buy this set up I would end up with the 6ul 17x8 +40. Noting that with this set up, only a 4-5mm difference, it seems all the affects felt with say 17x8 +35 or +36 wheels are resolved? Os the balance really this delicate??


Thank you for all the thoughts on this subject


***Edit
To help with the subject discussion I have removed the 16x7 +35 from the title and am leaving a few assumptions i hope can help.

Since this is mostly about offset and wheel width, but also began with the wheel diameter variable... I'm thinking it will work best to just assume that a proper tire choice was made for the 16s and that even with that, it will feel different from a lower profile tire on a 17" or 18" wheel.

to pin offset and width down, thinking with these assumptions might help?

1) the same diameter wheel
2) identical tire brands
3) tire and wheel width fit in accordance with the wheel/tire manufacture recommendations

[churchx]

People running 17x9 for look reasons won't care about changes to handling. People fitting 17x9 to fit widest tires for extra grip in auto-x are willing to do sacrifices for that grip. I'm not sure both cases are of "it seems all is well" if you are not from those camps but just daily drive or do mostly HPDE.
Though i'm not sure if less by 10 offset then stock is THAT noticeable and THAT much affecting handling either. I'd rather bet that it would pass under change detectable by my "butt dyno" or would pass as something i'd quickly adapt to and won't notice later on. Scrub radius, yes, heavier steering, yes .. but my butt dyno may err within rather wide margins, that can easily float around due placebo effect too
At the end my personal choice was to not care about flushness/looks at all. Only about price/strength/weight. Close to stock size (and offset) used forged wheels fit the bill for me, with 17x7.5 +47 & 16x7 +43 for winter. Light, cheap, strong. Yes, not flush, but i didn't care in first place, which widened acceptable choices, and certainly didn't affect handling much vs stock. Among classifieds one often may see fine forged wheels for cheap, but as they often come in common for old subaru-s offsets of +42 to +48, flushness shouldn't be among main priorities

[Icecreamtruk]

For what its worth. Changing from +45 to +20 (25mm spacer) in the front, for clearance issues made the car handle very differently, specially on track. Going from +45 to +40 made no noticeable change to me. This was all done on the same tire (225x45), on the same wheel (17x8 +45), on the same day, just using spacers to "tune" for lack of ajustable suspension.

Currently running 17x9 +35 on 245/40 tires. They feel better than all of the above combinations on track. On street, I really dont care, I just want to go faster on track.

[venturaII]

Hmm...I'm running 16x7 +40 and while I've never tried the same size wheel in a +35 offset, I have a hard time believing that just 5mm would turn it from the fun, responsive car it is now, into something as described above. Perhaps tire choice was more to blame than the change in offset?

[mav1178]

You are not going to see a huge difference in handling if you look at front/rear track. What you are proposing is the same as adding 10mm spacers to stock wheels.

What WILL make a big difference is going to 16" wheels and much larger sidewall. You will lose quite a bit of steering response and the steering feedback will be much more vague.

[venturaII]

Originally Posted by mav1178

You are not going to see a huge difference in handling if you look at front/rear track. What you are proposing is the same as adding 10mm spacers to stock wheels.

What WILL make a big difference is going to 16" wheels and much larger sidewall. You will lose quite a bit of steering response and the steering feedback will be much more vague.

While I'm full aware that that's the theory and I understand it thoroughly, I believe tire selection has FAR more impact on feel and response than the extra 1/2 of sidewall. Obviously, if you went from a 17" to a 16" wheel and kept the tire brand and model the same, then the statement above would most certainly apply.


What I find funny is everyone getting all hung up on 'response and feel', and yet every bushing in the car is still stock, stock sway bars, stock alignment, etc.

[mav1178]

Originally Posted by venturaII

While I'm full aware that that's the theory and I understand it thoroughly, I believe tire selection has FAR more impact on feel and response than the extra 1/2 of sidewall.

I always make my statement assuming "all else is equal"... the last thing I want to do is to get into threads where we are discussing 3-10 points of variables.

Too many owners of this car simply do not have enough experience to know what a car with blown bushings feel like.

[surfwaxsmitty]

Originally Posted by churchx

People running 17x9 for look reasons won't care about changes to handling. People fitting 17x9 to fit widest tires for extra grip in auto-x are willing to do sacrifices for that grip. I'm not sure both cases are of "it seems all is well" if you are not from those camps but just daily drive or do mostly HPDE.
Though i'm not sure if less by 10 offset then stock is THAT noticeable and THAT much affecting handling either. I'd rather bet that it would pass under change detectable by my "butt dyno" or would pass as something i'd quickly adapt to and won't notice later on. Scrub radius, yes, heavier steering, yes .. but my butt dyno may err within rather wide margins, that can easily float around due placebo effect too
At the end my personal choice was to not care about flushness/looks at all. Only about price/strength/weight. Close to stock size (and offset) used forged wheels fit the bill for me, with 17x7.5 +47 & 16x7 +43 for winter. Light, cheap, strong. Yes, not flush, but i didn't care in first place, which widened acceptable choices, and certainly didn't affect handling much vs stock. Among classifieds one often may see fine forged wheels for cheap, but as they often come in common for old subaru-s offsets of +42 to +48, flushness shouldn't be among main priorities

Good thoughts! Lap times likely plays a big role rather than car fun/feel for a few of these wheel setups. and yeah, same perspective on wheels here. That's why i am considering the 6UL wheel, similar in weight to RPF1 yet stronger and seem to be made very well made.

Im frequently searching the classifieds, ebay, and CL for wheels like you described. Yet many of the forged wheels frequently posted on ebay look to have a tough race/daily history, and just don't feel it. Definitely waiting for a nice lightly used set that is already stateside to pop up!

Originally Posted by Icecreamtruk

For what its worth. Changing from +45 to +20 (25mm spacer) in the front, for clearance issues made the car handle very differently, specially on track. Going from +45 to +40 made no noticeable change to me. This was all done on the same tire (225x45), on the same wheel (17x8 +45), on the same day, just using spacers to "tune" for lack of ajustable suspension.

Currently running 17x9 +35 on 245/40 tires. They feel better than all of the above combinations on track. On street, I really don't care, I just want to go faster on track.

Definitely, thanks for sharing. Comparisons made after no additional changes are very helpful!

Originally Posted by venturaII

Hmm...I'm running 16x7 +40 and while I've never tried the same size wheel in a +35 offset, I have a hard time believing that just 5mm would turn it from the fun, responsive car it is now, into something as described above. Perhaps tire choice was more to blame than the change in offset?

Originally Posted by mav1178

What WILL make a big difference is going to 16" wheels and much larger sidewall. You will lose quite a bit of steering response and the steering feedback will be much more vague.

This is certainly true. I was considering mentioning tire choice in the initial post but had already written so much haha.

For the sake of this discussion, let's assume that tires chosen for the 16s have a good sidewall stiffness, street tread, and an average tire weight.

Even with a good tire, as expected, there are differences in the feel of a 16" wheel with a taller sidewall; that's all fine.

Originally Posted by mav1178

You are not going to see a huge difference in handling if you look at front/rear track. What you are proposing is the same as adding 10mm spacers to stock wheels.

True, anyone who has added larger spacers to stock wheels feel free to chime in! People who have had their driven a stock or aftermarket any set up for a while and then, only, changed by adding 10-15mm spacer... Those experiences would help as well!

Originally Posted by venturaII

While I'm full aware that that's the theory and I understand it thoroughly, I believe tire selection has FAR more impact on feel and response than the extra 1/2 of sidewall. Obviously, if you went from a 17" to a 16" wheel and kept the tire brand and model the same, then the statement above would most certainly apply.

What I find funny is everyone getting all hung up on 'response and feel', and yet every bushing in the car is still stock, stock sway bars, stock alignment, etc.

Originally Posted by mav1178

I always make my statement assuming "all else is equal"... the last thing I want to do is to get into threads where we are discussing 3-10 points of variables.

Too many owners of this car simply do not have enough experience to know what a car with blown bushings feel like.

Good points! Lets try to assume all variables are controlled.

Since this is mostly about offset and wheel width, but also began with the wheel diameter variable... I'm thinking it will work best to just assume that a proper tire choice was made for the 16s and that even with that, it will feel different from a lower profile tire on a 17" or 18" wheel.

to pin offset and width down, thinking with these assumptions might help?

1) the same diameter wheel
2) identical tire brands
3) tire and wheel width fit in accordance with the wheel/tire manufacture recommendations


Thanks for all the responses and discussion!

[venturaII]

The one other issue I haven't seen mentioned is that more scrub will equate to more steering kickback. That said, I make an extra effort to avoid road damage when I run my summer wheels since I don't want to try and find a replacement for a discontinued wheel, so I can't really say whether I've specifically noticed more kickback or not. My winter setup is 205/55-16 on 16x6.5 +50 steels - a combo that feels quite a bit heavier than my summer setup, so there's too much changed to definitively say what I feel is caused by the extra 10mm offset.