Will putting 350Z wheels on my S13 cost me sharp responsiveness and steering feel?

[180SXkiwi]

I've a S13 180SX with R33 GTS-T hubs and rotors. I've been on a bit of a journey regarding wheels. When I fitted the the R33 rotors & brakes I fitted R33 GT-R alloys. They made the steering quite heavy and dull/ lifeless. I recently swapped to a R35 17"x7.5" wheel, and that really improved the steering feel and turn-in. I think the main reason is the offset, OEM on an S13 is +40, the GT-R wheels are +30 and the R35 wheels are +45. However the GTR wheels need a 5mm spacer so the inside rim clears the coilovers, and the R35 wheels need to retain the spacer to clear the GTS-T 4 pot brakes, which means they are no longer hub-centric and fixing that is, for various reasons, problematic. So I want to swap them for a 17" Nissan wheel that clears the brakes without using a spacer. So after allowing for the 5mm spacer the GTR wheels in effect are +25 and hte R35 wheels are +40 offset.

I like the look of the 17" 350Z wheels on a 180, and I like the idea of a staggered set (the R33 GTR rims at 9" wide are just too wide on the fronts for the 215's I run on the front, while the 350Z wheels are 7.5" front and 8.5" rear).

What is stopping me taking the plunge with the 350Z wheels is the offset, the offset on the front wheels is +30, the same as the GT-R wheels. I'm reluctant about the 350Z wheels in case that leads to the same loss of responsiveness and feel as the GTR rims.

So my question is, am I right to blame the offset change for the loss of driving feel on the GTR rims, and is there anyone out there running 350Z rims that can describe their effect on handling and turn-in, steering feel and weight etc?

Any thoughts appreciated.

[centralcoaster33]

The mass and leverage will affect your steering input/ feedback. So you want to consider weight as well as diameter and offset. Also, where the weight is will affect your leverage. Putting on wider rims adds weight to the outer edge of your wheels. Moving the center offset of the wheel outward puts more strain on your hub via leverage. There's lots to read about the 'science' of this and you might want to spend some time educating yourself before making your next wheel purchase. For performance, I suggest comparing your desired setup to the stock wheels and weight, not compared to what other wheels you may have installed in the past. FYI - Staggered wheels with directional tread = no tire rotation options... unless you pull the tires off the rims and swap them left to right. A 10mm increase in offset doesn't seem like it would affect feel so much to me, but maybe. I wonder how much heavier those wheels were than your stock ones. No, I'm not running Z car rims so I can't describe the effects. Tire pressure can affect your responsiveness/ feel also.

[centralcoaster33]

I remembered a series of articles called "Making it Stick" from Sport Compact Car magazine. It had great information for wheels, suspension, center of gravity, roll center, etc. I recommend reading them. You can google search for it. Several car forum members actually typed it out. It appears the original articles are no longer available from the source. Super interesting stuff and likely helpful in your quest for good wheels and tires.

[180SXkiwi]

Thanks coaster. For the benefit of others, this http://maxima.org/forums/autocrossing-r ... t-car.html is the best link I found to the Making it Stick series. I'm not sure if you are making a point about the leverage effects of wider rims, or wider tyres. I'd considered the extra scrub of moving the tyres out, but I think you are slso making a point about the gyroscopic effects of wiht wider rims having more rim mass situated further out, which I hadn't considered.

The stock wheels and tyre combo were 17.5kg and +40 offset. The car had OEM rims on it when I got it so I weighed the unused spare. The GT-R and V35 (not R35 sorry) wheel and tyre combo are both just under 20kg. So a little heavier. Obviously lighter is better than heavier. I understand moving the centre out increases loading on the hub and on steering inputs. That goes to my question about whether the 350Z rims are a good idea, rather than whether they will simply fit.

I'm very happy with the driving characteristics of the V35 wheels. The only reason for swapping them is they do not clear the front calipers without using a spacer. My mistake is I assummed a later model 17x7.5" Skyline rim would clear earlier model skyline brakes that were originally inside 16x6.5" rims. I've never had problems with backward compatability of rims before. The 5mm spacer itself isn't a problem geometry-wise, as it results in the offset with the +45 V35 wheels being OEM, but it prevents the rim engaging on the hub centre, as the hub centric hole does not get close enough to the hub to get past the initial chamfered part of the rim. Engineering work-arounds to fix that all have their issues hence I'm leaning to changing the rims. Next time I will trial-fit first!

My interest in the staggered fitment is because I have always found the car to be tail-happy, even OEM they incline to roll over-steer (I've owned it since 1995) and the front is very trust-worthy, and these days it's 200kw at the wheels, so I run more rubber on the rear than the front, aiming to minimise extra weight and tyre width on the front for the reasons you touch on. It is certainly more pleasant to drive if the front tyre sizes are kept sensible. I'm currently running RE003's, which are not directional (but are asymmetric) so I can still swap them side to side.

[180SXkiwi]

Thanks. Posting an update in case in future someone else is looking at doing the same thing. I ended up going with the 350Z wheels. They cleared the calipers no problems, which was my main concern. The offset is 10mm off the OEM offset but it drives very nicely without being heavy or dumb like it was with the R33 GTR wheels. I'm very happy with the results.

[centralcoaster33]

Good feedback. Thank you for the update.