Ride quality: 16" vs 17" wheels ?

How do you define ride quality?

 

17” wheels look better and the lower profile tyres provide better steering feedback.

16” wheels ride better and are a lighter combination which can help acceleration, efficiency and in some aspect handling due to lower unsprung weight.

Physics is physics.

 

Agree with all (although looks are subjective)

Just wanted to add that tires themselves make a huge difference in comfort and feel. A 16" wheel with a high performance tire (and stiff side wall) can feel more harsh than a comfort focused touring 17" tire.

Tire pressures are another factor to tune feel for a specific wheel/tire combo.

IMO, the stock 16" tires are too soft. They have good grip but there's a lot of sidewall flex which makes the steering feel more vague

 

Don't discount the tire model in this. Some tires have nice, squishy sidewalls and some have firm sidewalls. While not a 100% rule, a softer sidewall tire will give lazier handling, and a stiffer sidewall will be more responsive. Not often a free lunch where you can have both. Run flats are particularly notorious for a poor ride.

 

All true.
My old jeep had huge sidewall tyres but they were triple ply All terrains which didn’t ride as well as you might think from their looks. They

 

I use 17" Power Spokes in the summer and 16" Spectre Grey Revolites in the winter. I haven't noticed a perceptible difference in ride quality or range, but both of those are the lightest, most efficient factory wheels available for the SE.

 

I have 17" Power Spoke rims and 16" Loop Spoke rims, with Hankooks on both of them. There is no question that the 16-inchers with their taller-sidewall tires compensate for Ann Arbor's potholes better than the low-profile 17-inchers. Your potholes may vary.

 

Don't let my wife read this. The red SE has 16s and she was happy with the ride. The blue SE will have 17s. She doesn't like riding in the 987 because of the harsh ride. the Konis in the 128i are in the middle so she is OK with that car on an occasional basis. I am not allowed to discuss the ride on the 4th gen Z28. She said any drive more than 20 minutes (this was in NY) and we have to take another car. Shhhh! The ride is identical. OK, identical!!
Lets delete this thread like the conversation never happened.
Thanks for helping a brother!!

Oh, and the 17s should be a little stiffer.

 

I cant compare. The 987 has PASM, -2.5 camber, a 3.6 instead of the 3.4, and a lot of track miles from the P.O. I think it is a little lower than stock, so every speed bump, etc. requires patience. I have to come to a complete stop, at an angle to get into my driveway. Also, I've had cars that size for the last 40 years. RX-7s, 944s, etc. as daily drivers. I don't like a "Buick" ride.

 

The main problem with ride quality is the short wheelbase. Big bumps will send you flying. If you want to nit pick over 16 vs 17" wheels, then maybe it's not the car for you.

 

Have you tried both sizes? I have and switching from 16" OEM summers to 17" all seasons made a significant difference in ride quality and handling.

I'm also not sure what wheelbase has to do with ride quality? There are plenty of mile long trucks with terrible/harsh ride quality and sporty (short) UTVs that could hit a speed bump at highway speed and be perfectly comfortable.

 

I went from 16" all-season Michelin Pilot Sport A/S 3 tires to 17" with crappy Pirelli run flats and the 16" tires rode far worse. The sidewall flex was not good with 16" tires and really made uneven roads feel much more bouncy. Maybe some like the cushy ride but for me, it felt bouncy.

 

Short wheelbase hurts ride two ways:

Pitch. When a single axle goes over a bump, there's more degrees of pitch the body moves. In bad cases, this creates a hobby horse motion.

Timing. When an axle hits a bump and compresses, it also has to return to the original position. A longer wheelbase gives the leading axle more time to complete its motion before the trailing axle reaches the bump. With a short wheelbase, there's more chance of having both axles unsettled at the same time, which equates to perceived poor ride quality.

General rule of thumb only, there's obviously many more factors into what determines ride quality.

 

So switching to 17" with all seasons made a difference for better or worse then?

Nailed it. Short wheelbase can be made to ride decent, but it has this principal to overcome and it becomes a significant trade off in cornering to compensate for ride quality over bumps.

 

Y’all would hate the ride in my smart 450 with Bilstein coil overs, urethane bushings, and 195/40-16 Yokohama S.drives!

 

Both are probably true to an extent but I feel like the suspension tuning and sprung/unsprung mass ratio makes much more of a difference than wheelbase.
For example, these things only have a 6" longer wheelbase than the MINI but would ride like cloud:


Another factor for perceived longer=better ride could be that in general, longer vehicles are intended to be more luxurious with softer suspension tuning and shorter vehicles are supposed to be sporty with stiffer suspension (or are cheap economy cars with crappy suspension).