While I was rebuilding my engine and redoing lots of other stuff I decided to go to 15 inch wheels and aggressive tires. I'd had a set of Allison's 15 inch wheels on a previous 2000 FI car and was pretty happy with them. This time I choose some Team Dynamic 7" wide wheels with a 35 offset (I believe factory offset is 25). I put about 200 miles or so on those with a set of 205 / 50 Yokohama rubber. Aggressive to say the least.
More recently I decided to try a set of 13 inch original steel wheels with Kuhmo 185 / 70 13 rubber. I knew this would be very different and below are my findings / thoughts on the two setups.
First, here is what we are talking about, again VERY different choices.
So, here is what I knew, what I didn't know and what I learned.
Cosmetics:
No question the originals look just that, original. I personally also think they look pretty good and certainly make the whole car look "correct". The Team Dynamics wheels make the car look much more updated. Many people mistook it for a much newer car when it had them on. I know several posters here have said they are "too modern" but they definitely update the car's looks. Overall just comes down to personal preference.
BTW, I sourced a set of "plastic chrome" beauty rings from Amazon that are much deeper than the original metal ones but hey, they were $28 shipped for four, they'll never rust, and I like the way they sit all the way down into the wheel leaving only the "pretty part" of the steel wheel exposed.
Ride:
Night and day. The low profile Yokos on the 15 inch rims are borderline harsh. The transmit every bump and are generally very stiff. (BTW, the car is sitting on a set of Vicks progressive springs in both cases). The original 13 inchers with the much taller sidewall Kuhmos are very smooth. As you would expect the taller sidewall cushions the ride and absorbs a lot of the bumps. Overall a lot less noise, harshness and vibration.
Steering response:
Again, night and day but of course advantage to the Yokos on the 15s. The Team Dynamics with these tires provides almost instant change in direction with steering input. The car handles very neutral with little over or under steer. (All the steering and suspension components are new in both cases as well). The first time I drove it with the stock 13s and the taller sidewalls I expected slower response but I was surprised by the magnitude of the difference. It takes considerably more steering input before anything happens and there is definite understeer. This is all of course expected with the narrower tread and higher more flexible sidewall but I was again surprised how much different. Not dangerous or anything, even fun, but VERY different.
Grip:
Again, obviously the 15s and Yokos provide more grip. I have done some fairly high speed cornering with that setup and never felt like I came anywhere near the limits of the grip. I haven't pushed the new setup much yet but clearly I'll find where they start to lose grip much sooner. On the other hand they would probably "let go" much more gradually and give some warning whereas I think the wider Yokos might be a rude awakening if they got there?
Low speed steering:
Advantage stock setup. One of the main reasons I explored this option was because the steering effort parking and turning at slow speed was SOOOO high with the wide tires. They stock ones one the other hand are very light to steer at slow speeds, like I remember these cars being when I drove roommate's cars new in the 70s.
High speed steering response:
As I mentioned above, the narrower taller sidewall tires respond much slower to steering input but not in an unpleasant way. Again, just like they drove in the day (although 185s are quite a bit wider than original 165s or 155s). The wide setup provided very quick steering response at any speed but not so much as to be twitchy. It did tend to tramp in ruts and uneven roads more however.
Alignment:
could never achieve factory specs with the wide setup (nor did I expect to) but I was able to dial in good enough number for straight tracking and good return to center and even wear. Not really an issue provided you have a good shop that will work with you. I am able to get to factory specs of course with the stock wheels.
Fitment:
On a related note, I ran the wider wheel with two stock spacers both front and back. Back was fine but with the wider rims and tires and 35 mm offset the fronts did rub the upper control arms slightly if at FULL lock. Never and issue otherwise but it made really tight turns when turning around or parking a challenge. The obvious answer is of course some wider spacers, probably 15mm. I see AR is selling sets reasonably now. That would also actually allow that setup to dial in closer to factory alignment specs.
So, where am I headed?
First, I need to spend a lot more miles driving the stock setup. I like it a lot so far. They car doesn't handle nearly as well and that is FUN! It is also much more pleasant to drive slowly (steering effort) and rides a lot smoother. I have a very different daily driver if I want to do fast and corner hard (2010 E63) so I think I prefer this car old school. Plus, I was very pleased with the stock steel wheel look once I painted them and added the hubcaps and beauty rings. Meanwhile the other setup is all cleaned up and properly stored in the garage while I decide.
If you want a Spider that handles like it is on rails and has great neutral steering response, AND can live with a somewhat hard ride and LOTS of low speed steering effort, go with the wide setup. Maybe with a 195 instead of 205? For now I am thinking less handling might just be the way to enjoy these cars more. Thoughts?
