Taller Tire Test (5.7% MPG increase observed on Honda CR-Z @ 55-65 MPH)

[CR-Z-BUZZ]

I have been looking at this thread for quite some time because I bought a slightly used 2014 Honda CRZ and it has the factory Dunlop tires (195/55/16)

I'm thinking about putting on a set of the Michelin AS energy savers in 205/65/16

Now I know this is oversized, duh! But I read nothing about them causing any rubbing issues, so I assume there are not any rubbing issues ...correct?

I have many motivations to switch to this size besides better gas milage, and they are: better traction in snow, I recently found out the factory tires had poor traction in snow evan though they have only 16,000 miles on them.

2. Better resistance to potential damage from potholes, having a treadwall that is 65 instead of 55 is over an inch more between my rim and the edge of nasty pavement.

3. I surmise that having a tire that has an overall diameter which is about 2" taller is going to make the ride less jittery, and that is less noise too.

So, I have looked about on google images, and can not find any pics of a Honda CRZ with the stock rims but with the taller 65 treadwall tires, I'd imagine it will look better..but i can't find a pic...anybody? This should give the appearance closer to a cross-over vehicle, should lessen the gap between the fender and the tire as it would do if it had lowering springs.

Yesterday after work i drove it to Discount Tire, I'd been doing business with them for decades..really trust them. And as I suspected, he'd say "that won't fit".. and guess what? He said "that won't fit".. So with that said, I said there is a forum (this one) and at least one poster said this size will fit. I'd been thru this putting wheels and tires on my '12 Camaro, it was like being on trial..had to tell them dozen's have put the size I want with no rubbing issues..

So I expect "yes they fit, no rub issues"..that said let's go from there..the
tires I'm told will have a $75 rebate from Jan 1 to the 14th so I said I'd possibly come back next week. He also told me they offer the same tire with a higher speed rating, will look into that later.

BTW Discount tire does not offer siping service anymore, a process which cuts micro grooves into the treads to get better traction.

Other tires of that size that interested me were the Continental "pure contact", similar to the Michelin's in that they are an energy saver rated tire and have an evan higher treadwear rating, slightly greater speed rating. The price was lower but with the $75 rebate (only avail. when buying 4 tires)..than the Michelin's would cost less.

Driving the Honda now about 1K miles, I find the "sport" mode to be a bit too
high rev. so if I'm lowering my revs with the taller tires than it might seem to be more useable. Mine is an automatic so I'm not concerned about more clutch wear and tear.

BTW, one of my tires has a slice in the sidewall, it's not buldging now but it could lead to a blow out, just another reason to motivate me toward other tires. The Honda CRZ forum does not regard the factory Dunlop tires very highly. It seems nobody at the Honda CRZ forum is at all interested in this type of tire/wheel size, they all went to 17" or 18" rims with lower treadwalls and or lowering springs. This thread was found doing a google search for "taller treadwall or taller tires...honda crz"..images..

I highly recommend Discount tire, I've bought tires and wheels from them on my last 4 cars over the last 24 years, they never ripped me off (to say the least)...and the life time warranty is really a great deal. That other place has the "out the door" price..yeah, they told me the price and I went out the door

On one hand I hate to replace tires with only 16K miles on them, I guess a salvage yard may give me a few bucks for them,..but on other hand the benefits might actually be worth it, btw my 1st post..t.i.a. and H.N.Y!

[mcrews]

it is easy to tell.
The biggest problem will be the strut tower. is it over the tire or behind the tire.
On my Q45 the bottom of the tower was just over the tire. I only had about 1" of clearance.
you should be able to feel around the tire and see what parts are close to touching.

btw, my tire guy mounted up the size I wanted (before I ordered the set of 4) and made sure it didn't hit anything. your tire guy should do that if you are a good customer.

and yes, I was VERY pleased w the results of 'upsizing' on the Q45. Better mileage, better look, little better ride(Q45 had electronic shocks so it had a pretty smooth ride to startwith)
good luck!!

[Magician]

just goes to show you economy wasn't the priority for the CRZ... otherwise the gear(s) would have been taller.It's great that you figured that out and compensated with taller tires! I know I'm a few years late on seeing this...

[CR-Z-BUZZ]

Took my Honda CRZ into Discount Tire today to have the 205/65/16s put on, did not fit, not evan close. They put one on the front, lowered it, it rubed hard against the whole inner wheel weld. What is up, did original poster do something to moddify his car to fit such as the wheel welds?

I said something about "spacers" and they explained that would leave less of the lugs so they could strip over time, so that was no go.

My Honda has the factory wheels, maybe I'd have to get aftermarket wheels with a different offset? I have not re-read the original posters post but I am pretty sure he said "on the factory wheels"..sooo..what am I missing here?

They said I could go with smaller tires but I said that was the whole reason to get them in the first place. They said they could try putting on a 205/60/16 but if it rubs while I'm driving it than I'd not be covered (or to that effect I'd be taking the hit). Note: them lowering the car and feeling to see if they rub is not the same as it being driven, which means, on corners or when hitting bumps, turning, they could rub. I experienced that kind of issue on one of my cars when I had a flat during a trip and went to the nearest department store which put on a set that had a taller treadwall and perhaps a bit wider..looked cool, but soon I noticed a rubbing sound...When I got home, I took it to Discount tire and..I don't know how they did this, but they put what I paid for those tires at Wallmart toward a set that fit? Not the first or only time they bent over backwards to help me..

BTW I had decided to have my factory tire put back on, I did not purchase any new tires at this time, they gave me back my $100 deposit I had on them (transferred stock from another store).. they did not charge me one thin dime for all that trouble and non-sence. They didn't even try to make me feel like the fool that I was, but I was doing a pretty good job of that myself which is why I keep going back to them.

I have not looked into this but I wonder if I had new springs put on it to raise it up about 1 1/4". This is going to be difficult to research because everybody else that does mods to the wheels and tires is doing the exact opposite; putting on larger wheels, shorter treadwalls and or lowering the suspension either by changing the springs or converting to coil-over springs. I think it would be cool to have it raised up sorta like a compact SUV.

[rmay635703]

Every year model is a little different,

Sometimes shock/spring spacers help, other times different offsets help

Other times the wheel well is just too small.

A hint though
185/65, 195/65 and 195/60
Are both very common energy saver sizes , a little is better than nothing.

Good Luck

[litesong]

Originally Posted by rmay635703

......185/65, 195/65 and 195/60
Are both very common energy saver sizes.....

Never worried about energy saver tires, but got used tires, 15 inch wheels, & switched our 195x65x15 inch tires from our Elantra to our 2008 Hyundai Accent front, which originated with 175x65x14 inch wheels/tires. Found some 195x60x15 tires & they are on the Accent rear. Last summer, the EPA-rated highway 32MPG Accent got 18 tanks of gas in row, that were 40+MPG(no MPG computer). Our previous high tank in 10+ years was 45MPG. Our highest tanks in the 18 straight tanks, was 45, 47+ & 48+MPG.
On the Elantra got used 17 inch wheels with 225x55x17 inch tires, & 18 inch used wheels with 225x45x18 inch tires. The Elantra has a 6speed tranny, & 60 MPH rpms dropped from 2030 to 1900. With the much wider tires, I note no overall MPG loss. Under slower driving conditions, MPG went up.

[Angel And The Wolf]

Originally Posted by CapriRacer

But there are a couple of extra variables that are clouding the picture

Michelin 205/65R16 Energy Saver A/S are 8.6% taller for an increase in travel, but 5.12% wider for more rolling resistance than the Dunlop 195/55R16 SP Sport A/S.
combined, you should get 8.16% better mileage, but you are getting only 5.7% better mileage, so there is another factor fighting the increased mileage. It might be the 8.6%increase in air going under your car. Better results might be obtained if you could keep the ground clearance the same.

[CopperMan]

I've found that cruising at an rpm just high enough so the engine makes enough torque to remain in high gear yields good mpg. I set up a Ford 300 inline six with a 5-speed and some hard compound 31" skinny tires on it, that thing was averaging 17-22 mpg in the bronco I installed it in. Tall tires certainly can help, but only if the engine can keep the vehicle moving without overworking. Inline engines and/or diesels tend to have a longer stroke, which produces low speed torque and has potential for big mpg in the correct conditions. If you have a diesel engine that produces 600 ft/lbs of torque at 1200 rpm, gear it so it cruises at 70 mph at 1200 rpm, and put that engine in a lightweight, low drag vehicle, it's going to have some serious power while still getting great mpg too. The cool part is, you don't even need to push your foot down any on hills to maintain speed, the engine doesn't really care what it's hooked to, it just does its thing.

[litesong]

Originally Posted by litesong

... got used tires, 15 inch wheels, & switched our 195x65x15 inch tires from our Elantra to our 2008 Hyundai Accent front, which originated with 175x65x14 inch wheels/tires. .....On the Elantra got used 17 inch wheels with 225x55x17 inch tires, & 18 inch used wheels with 225x45x18 inch tires.

With the various successful experiments I''ve done with used tires on my cars, I got carried away, even thinking very slightly different diameter new tires could work on the same axles, even powered axles..... hey, the tires were "only" 2/10ths of an inch diameter difference. However, 2/10ths of an inch difference is about the same difference as a new tire & an older tire of the same tire with about 40% to 45% of the legal tread worn away. Many websites warn against mixing tires on the same powered axle, even of the same type, which have different tread depths. Tho the powered diameter differences aren't much, the smaller diameter will rotate as much as 5 more revolutions per mile of travel. That rotation difference is being allowed by your differential. Then, you are continually depending on the differential, not just in turning, which isn't what the differential was designed to do.
Also, my non-engineering approach to used larger tires probably means I'll pay for suspension work, probably sooner than later. But, its sure cool to see big wheels & tires on the cars, now.

[pete c]

I will never understand manufacturers gearing choices. Seems like every manual trans car I have ever owned could have had a significantly higher top gear.

This was sort of understandable in prehistoric times with 3-4 speeds. You had to consider the spacing of ratios. But a 5 or especially, a 6 speed?

I test drove an MT 6 speed once and immediately thought, WTF is Honda thinking? This thing is supposed to have efficiency as a selling point and I can run around all day at 35 mph in 6th. Even pull slight hill.

I suspect the answer to why they do this is that they cater to people apparently unaware of the fine art of downshifting and car mag writers.

Take a look in a road test in C&D. They post top gear acceleration stats.

They realize that some people will look at these numbers and think, huh, car A pulls better than car B in the 50-70 test. A must be better! Also these writers obsess over close ratio trannies and staying in the "power band".

It's a freaking road car, dummy. It is not a track car. 3/10ths of a second off the lap time is irrelevant. But people are dumb. And salesmen that will point out these irrelevant stats are shameless.

My '09 Sonata is probably the worst example of this I have owned.

It can be lugged around at 30 mph in 5th on level ground just fine. It really needs a 6th gear.