Honda Insight Forum banner

1 - 9 of 9 Posts

·
Premium Member
Joined
·
679 Posts
Discussion Starter #1
I've scanned all the old posts about folks using different tires, like the 195/55 Dunlops and Toyos, and most of the threads kind of dwindled away before people posted their real world results.

By the dates of the old threads, quite a few people have had these other tires on for a while now and should be able now to give some hard data on their experiences.

:arrow: Can you guys who've been running these tires give the skinny on them?

:?: PSI used?
:?: MPG vs. Stock?
:?: Wear issues?
:?: Real world handling?

After your time with them, are you happy? Sticking with them? Going back to stock?
 

·
Registered
Joined
·
1,123 Posts
I'm glad you started this new post.
But a moderator should move it to the "Modifications and Technical Issues" section.

For the benefit of others I'll start by copying the info I posted last night on the tire pressure thread, (even though I know figgy already read it).
Within this info I have added more details today to answer your questions.

Tire review and tire width/fuel consumption:

I upgraded to 195/55R14 Toyo T1S ultra high performance summer only tires on my OEM rims. These tires are the exact same diameter as the OEM tires and there rated load max pressure is 44psi.

I use 44 psi front and 40 psi rear. After some testing on a skid pad I determined I needed 44 psi in the front to have the ideal minimal amount of sidewall flex during heavy cornering loads.
Because these tires have so much more air capacity there is no benefit to increasing the pressures to 50 psi like there is when using the skinny 165/65R14 OEM tires. I tried the Toyos at 50 psi all around and there was no difference in fuel efficiency at all, but there is a perceived increase in rougher ride in the bumps from the harder tires. These higher pressures also decrease the size of the contact patch. So grip will be reduced at 50/50 psi compared to the optimum 44/40 psi front/rear I found works best through skid pad testing with these specific tires. Huge Monster trucks only use 5 psi in their huge tires because of the huge air capacity in their tires.

These tires have about the same road noise at the OEM tires (which is impressive for a tire in this performance catagory).
But the Acceleration, braking and cornering grip and comfort level is much improved over the OEM tires. These tires improve the feel of the car at all speeds and doesn't track the road like the OEM tires.
There is definately much less tracking of grooves on the roads.
I'm not exagerating when I say that just changing these tires makes it feel like i'm driving a different car! Feels like i'm driving a larger car!
Driving over deep puddles with the OEM tires can be scary as the car jerks to that side. With these tires under the same conditions provides a very different experience, it just channels the water and resists hydroplanning in a way that it eliminates the jerking feeling. I feel so much safer driving with these tires.

Fuel consumption is usually about 10% more with these tires.
But that just an oversimplified answer.
Fact is the fuel consumption increase seems to be less then 5% at low speeds and 15+% at high speeds.
These tires have a higher rolling resistance (stickier rubber compound) AND they increase aerodynamic drag (because they are wider).
These factors decrease the maximum speed at which lean burn can occur. This means the most noticeable increase in fuel consumption (almost 20%) occurs if you are comparing fuel consumptions near the lean burn threshold. Depending on the wind, how flat and smooth the roads are and the temperature this happens anywhere between 95 to 110 km/hr. But these are very specific conditions and speeds so this high a fuel consumption is only short term and rare.

Driving fast 110 km/hr or very fast 130 km/hr (rarely in lean burn) fuel consumption seems to be 10% to 15% more.
At slow speeds 60 to 80 km/hr (at a constant speed so increase tire weight is not a factor) the fuel consumption increase seems to be minimal maybe 5-10%.

After I re-read all this stuff, I have to admit most of these details are overkill, all you need to know is that overall my average is about 10% increase in fuel consumption per tank with these tires. And that speed is still the largest factor that determines the Insight's fuel consumption.
An Insight driver with OEM tires that always drives at 120 km/hr will always use more fuel then the Insight driver with wider tires that always drives at 100 km/hr.

Us 5 speed Insight drivers with wider tires get such a rap for "destroying" our fuel efficiency but the fact is we still get better fuel efficiency then CVT insights on OEM tires. :wink:

NOTE: These are all perceived observations.
The only way to reasonably test the actual differences is to get 2 identical Insights with cruize control except one of them have these tires on them. Drive both cars at the same time over a 100+ km loop at the same speed on an open highway where traffic will not get in the way and ideally not stop or slow down at all. Then switch the wheels and drive the same 100 km at the same speed again to eliminate the differences between the cars themselves.
 

·
Premium Member
Joined
·
679 Posts
Discussion Starter #3
Tests

Thank you for posting more details.

Are there others out there with these Toyos or the Dunlops or others?

With regard to testing, we do not have cruise control, but my girlfriend now has a (theoretically) identical 2001 where we could track each other staying in 5th and driving exactly the same speed with only feather acceleration by never shifting. Both are 2001, approximately same miles on them.

It seems each car is subtly differenent, so maybe we will try to calibrate this by first testing with the OEMs at exact same pressures and conditions. If we can't get that to match, but it is consistently different by the same amount, we could still do the test.

I did some repeat tests on the same stretch of track for warm air mods tests, and they were quite reproducible one after another. I am not sure if a <5% difference would be noted, however. On the other hand, if the difference is so small that it isn't easily observed, and the handling is better, then the question is answered!

Of course, that test also means one of us would have to get a set of new tires...

Who would be the lucky test hamster? :roll:
 

·
Premium Member
Joined
·
891 Posts
I have 185/60R14 H-rated Lifeliner SLE tires by Cooper. I inflate to 45 psi or so. I have noticed similar improvements in handling and worsening of mileage, although the mileage hit for me has been masked considerably by a major change in climate and in driving conditions -- short trips in cold weather when I used to be doing 100+ mi/day in mild SoCal weather, often with an evening seabreeze tail wind.

I didn't look around much for tires, I just knew that it would take too long to get the OEM tires and I wanted new ones before driving cross-country, so these were good tires that were available the moment I showed up at a tire store on Cape Cod, MA. As it turns out the entire cross-country drive was done in either heavy cross-winds or flash-flood level rains, so I was very happy to have these tires.
 

·
Registered
Joined
·
700 Posts
I had the same experience as Guillermo with Bridgestone Potenza RE950's (ultra high performance all-season tires). I drive 95% at interstate speeds and my mpg was down 15-20% over the 2-weeks that I had them.

They did handle much better, and are probably much better in the wet.
 

·
Registered
Joined
·
89 Posts
Dunlop SP8000 195/55/ZR14 long-term

I started with these Dunlops when my '00 Insight had ~ 6K miles. I've put on close to 20K miles since then. My lmpg was ~ 52 with the OEM tires at 38 psi at all corners. That's the only inflation level I used. When I started with the Dunlops, at the same psi, I averaged ~ 3.5 mpg less on my first several tanks. As my full recalibrations of the battery pack (the pack was eventually replaced under warranty) became more frequent, I lost another 1.5 or so more mpg over time. So, the comparison at 38 psi was ~ 52 vs. 47 mpg.
I later went with 40 psi on the Dunlops, and started getting mpg of ~ 53 per tank. For the past 1K miles or so I've been using 44 psi (the max rating for these tires) on the Dunlops, and am getting ~ 61 mpg. I haven't tried a higher psi level. The tires are probably half worn, so they're probably good for a total of 40K for street driving only. At 44 psi, I've been driving mostly suburban streets with speeds ranging from 37-55 mph, with very little a/c use. I do regularly shift at redline in 1st gear, and do take 2nd gear up to speed at wide-open-throttle.

Real world handling is not even close when comparing these Dunlops to the OEM tires. With the Dunlops, there's a very small loss in handling in going from 38 psi to 44 psi, in real world driving, but the extra mpg is huge. These are very high performance tires, and they do deliver an incredible improvement in cornering capability to the Insight. They're superb in the rain, and allow for better braking vs. the OEM tires, dry or wet. In hard braking, I've yet to activate the ABS, which was something that wasn't unusual with the OEM low-traction tires. The car is much more stable in very windy conditions, tracks much better on road irregularities, and offers a better feel for the steering.
 

·
Premium Member
Joined
·
1,658 Posts
Mitch - Very interesting; which Dunlop tyre are you on?
 

·
Premium Member
Joined
·
679 Posts
Discussion Starter #8
Sizes & Potenza RE950

Holicow

Were the Potenza RE950s 185/60-14 sized?

That is about the same diameter, but a tad larger, I believe vs stock.
 

·
Registered
Joined
·
89 Posts
Dunlop SP8000 195/55/ZR14

The aforementioned Dunlops on my car are SP8000 195/55/ZR14.
 
1 - 9 of 9 Posts
Top