OK, so I lowered my Stang last year with the Roush Suspension and I can feel a slight difference in ride harshness, but I'm more than happy with the much better handling and control that I gained. My question is, for those of you that are lowered and have 20's....how much would you say the 20's impacts ride comfort vs 18's....a little, a lot? If I lived somewhere like Arizona or California, I wouldn't even debate it, but wondering from those of you that live somewhere with crappy roads like we have here in Michigan. Any insights are appreciated.

 

I've been looking for some info like this as well, because I have already lowered my car and keep looking at new rims, and want to know about the difference in ride between 18, 19 and 20" rims...

Please help us!!

 

I'm in Ohio, I lowered my car with the steeda ultra-lite springs, I have been through all 3 sizes of wheel/tires. My latest (hopefully last ) set of wheels it the 19". I got the 18" gt500 wheels and the ride was fine but I felt the wheels looked too small, the tires were too short and my spedo was off about 2mph, My next set was FRPP Spyder 20" and I thought they looked too tall with the lowered vehicle, they were also not wide enough (20x8) but I got the same height tire that the factory 19" tires were so my spedo was correct., They are much heavier and i seemed to get less traction. I ended up with the 19' RTR's.

 

Thanks dwtc. Would you say there was much of a difference in ride harshness when going over bumps/rough roads, between the different sizes? I'm definitely going with a 9.5 or wider wheel in the back, as I plan to supercharge eventually too and know I'll need the traction. I'm just curious if lowered with 20's and our potholes, if it would be too much. Thoughts?

 

Second picture with silver rims is better I think.. Reminds me of silver RTR

 

im running a full eibach suspension with 20's in MA. We have some terrible highways let alone roads and have no issues. I think it handles and rides better then stock. I have the prokit springs and actually contemplating the sportlines for a lower look. 20x10 in the rear by the way.

 

Thanks...good to know. My Sis lives out in Boston and I can attest to your roads being on par with ours here in Michigan. Since I only lowered it 1" with the Roush suspension, I should be good with 20's too. Time to start shopping!

 

I dig both the 19's and 20's on your car dwtc, for whatever reason the 18's actually look a bit small for your ride.

Anyways for whatever its worth, anytime you decrease the height of the tire sidwall, impact harshness (all things being equal) will most likely increase since there will be less sidewall deflection.

Also you have to take the overall wheel/tire weight into consideration as well. Increasing the overall unsprung weight will diminish the strut/shocks ability to control the wheel which could contribute to the harsh ride.

If your going to increase the wheel diameter, its well worth looking into a forged wheel to keep unsprung weight in check and/or upgrading the suspension as well in order to cope with the added weight.

And consider the optimal OD for any rim combo is 27" - with 20's a 255/35R20 will net a 27" dia tire, also (and there is limited support for this size) a 295/30R20 is 27" in OD as well.

 

I'd say the ride is not compromised hardly at all. I only lowered it 1" and my rear tires are 315/35 on 10.5" wide rims so the side wall is hardly shorter than stock the fronts are 275/35 on 9.5". The width actually makes it easier to miss pot holes. And the wheel tire combination is lighter than the stock 18".

 

Thanks all. That makes sense about the wheel weight, so I'll keep that in mind while picking out wheels. Basically, the lighter i can go, the better (both performance and ride quality).

 

My 07 is slammed with the Eibach Sportline springs on 20's and I do mean SLAMMED! My rims are the Torq Thrust M by American Racing and I also have steel LCA's, Eibach swaybars, a steel panhard, and aftermarket C&C plates.

My ride isn't what you would consider "comfortable" by any stretch of the imagination, but after some adjustments and tweaking of the UCA, C&C Plates, and setting the sways to a "neutral" position along with hollowing out the rear wheel well, I actually prefer the rife of my own care compared to every other car i rode in. I had a first time passenger along for a ride home tonight and I told him "sorry for the upcoming ride beforehand" as we got into the Mustang. After I pushed some centripetal force on the car turning on a main road and barreling around an incline freeway onramp, my passenger responded that the ride was actually pretty good and nowhere near as bad ad I led him to believe it was going to be.

My suggestion first and foremost when running a lower profile suspension and tire size; RUN A BIGGER TIRE! I'm thinking about stepping on rubber all around the 'Stang from 255/35/20's that are currently on all four corners to 275/35/20's up front and 295/25/20's in the rear. I must digress that my suspension isn't remotely "complete" and because the components are super stiff on "stock struts" and shocks, the back-end of the car is fully capable of whipping out from behind me if I get into it around turns and cornering. Remember that your suspension parts and components most likely "weren't" engineering to handle the increased load of 20" rims and may be pushed beyond their limits of balancing the load of the car when you install the bigger rim and tire size.

The roads up here in the PAC NW are atrocious to say the least. We have 9 month long rainy seasons that are mixed with ice and occasional snow (i know your winters are worse there!) showers annually make for roadways that are full of potholes and all around crappy to drive on. I can relate to the roads you have in the Midwest is what I'm trying to get across but we are far from duplicating the asphalt you guys have to drive on up there.

Just ear in mind that too stiff or too soft of a suspension setup = potential catastrophe if you aren't careful. I have a pretty elaborate plan for my car when all os said and done but the absolute first building block for me is suspension. I am finding out the hard way that suspension is an art form in my opinion. If you don't take all aspects into consideration, you could end up being another street racer who went and made himself into a spot on the roadway. I'll be quite a few of the street racing accidents are caused by suspension that is improperly setup and (or) installed by the kids who own and drive the car(s). Your setup has to be harmonized with the vehicle and total load on all 4 corners to get the full benefits of surface grip and maintaining balance on the road way.

 

Would love to see pics of your slammed stang Pete

 

I bought a 2005 mustang that had the Eibach pro springs and 20" wheels about 9 or 10 months ago. I will qualify it by saying dude had some rather cheap steel 20" wheels that weighed in around 35 lbs a piece and it was sitting on 245/35/R20 tires.

It felt absolutely terrible riding on the freeways (in California) and did a number on my brakes trying to stop those behemoths. I just got them replaced because they had warped from getting too hot. It stole the joy away from driving the car at high speed because you could feel every single **** pebble on the road, every little crack or uneven spot.

If you've got to have 20's, I would pony up the extra money for some high quality lightweight forged aluminum wheels. And I would invest in an upgraded brake kit to handle it. Even then, your ride quality is going to feel "sporty" to say the least.

Or there are some decent 19" options that'll give you a little more rubber to make it a bit more of a comfortable touring type car. Only problem is the tires will typically cost you about $20 or $30 more apiece for R19 tires and you have a pretty skinny selection to choose from with 19x8.5 wheels.

For me, the look of the 20's (and it was sick looking) wasn't enough to surrender ride quality and everything else. I pulled them off about 3 or 4 months ago and put Aluminum Saleen Racecraft 18".... The improvement in ride, the stopping and the acceleration was ridiculous. It feels like a completely different car now.

 

Thanks everyone. I really appreciate the info. I think all things considered, I'm going to try to stick with a forged wheel....and so far, considering costs and looks, I'm liking TSW's offerings. I'm just trying to decide which ones would look best on my ride and if I want to go with 19's or 20's, since they offer both.

 

My 2007 GT was lowered with Steeda Sport springs. The suspension was further augmented with Steeda HD strut mounts and Koni STR.T shocks and struts. On 20" Saleen wheels, the ride was noticeably rougher than on the stock set-up, which consisted of 17" wheels. In comparison, my 2011 5.0L, which rides on FRPP 1" lowering springs among other suspension modifications and 19" Forgestar F14's, features ride quality that, in my opinion, is actually better than stock.

 

That makes me think that weight really makes a BIG difference, because I bet those Forgestars are a lot lighter than the Saleens.

 

Im running eibach sportlines with 19's on 275/35/19 bridgestones and the ride is not bad, but stiffer then stock.

 

I agree. Silver looks better. Not sure what's up with the blacked-out trend these days. Overall, still a very sharp looking car.

 

My 06 had the stock 17x8, pirells... Changed to wider 17 inch front tores on the stock wheels, and 18x9 rears with same width/ 27.1" diameter as stock... Hated the change in ride, shaved .2 off the 60 foot time with the wider rubber, but dropped trap speed from 103 to 99... Thought that was weird... Anyways, i didnt like the look after doing it, as the taler rubber up front made the rears look small even though same diameter as stock- sooooo...

Changed to ARTorq-thrust IIs, 17x8 ( maybe theyre 9, tired cant recall right now) but know they had a 5.5 backspace instead of 5.94... Taller 27.9" nitto rears ( 275-50-17 i think) and 27.1s up front (255-50-17 i think) and its got that old hot wheels car stance, stuffed wheelwells, and rides better than stock... One huge difference, bumpsteer completely disappeared? The wheel offset shoulda made it worse, but feels to me like maybe the stock wheel offset / scrub radius might not have been optimal for eliminating bumpsteer.

Wonder if nyone running 1/4 spacers up front noticed a bumpsteer improvement with no other changes... One problem with the 275s on the 5.5 bs, the drivers would just barely rub if bottomed... I made some snubber spacers to limit bottoming, and added some airbag boosters... Put about 5000 miles on it this past week, love the highway ride now- amazing what a extra .5" of sidewall does for ride quality.

I think changing to larger wheels definitely needs accompanied with softer bushings to keep harshness anywhere near stock, otherwise the firmer tire just beats up the car and passengers... Ive ridden in some with 20s that rode fine, but pretty sure it took bushings and/ or shocks to smooth out the harshness.