Wheels, Rims, and Tires

As winter is finally coming to an end, the topic of changing tires comes back.

At the same time, I am wondering if it is worth while installing 165/55 x 15" or 155/55 tires in the front to get a better balance ?

I have not found any Eco tires in this dimension but actually think that having none Eco tires in the front might further help the equilibrium as Eco tires tend to have harder and less adherence than normal tires.

Any thoughts on this compromise and non Eco type? Do you really think we can measure the difference in range with full set of Eco and half set (Eco at back and normal in front)

Thanks.

I checked the circumference of a 165/55 15 versus 145/65 15 and they are quite near.

I am ready to order some cheap NangKang tires to try it out if some one can confirm that a 4 inch from wheel can take a 165 wide tyre instead of an145.

Thanks
N

I did some checking and there is no tire that properly fits our teeny, tiny 4 inch front rims other than a 145. All the 165's that I could find specify 5.0 to 6.5 wheels. I don't think you would see any improvement squeezing a too wide tire onto a too narrow rim . . . . guys have been unsuccessfully trying that on motorcycles for many years

Even the 175's on our 5 inch rear wheels are about maxxed out. Ideally, a set of 15 or 16 inch 5.5 inch wheels would be perfect - You could then use a suitable size tire with no problems. Unfortunately, I think we're looking at $1500 or so just for a set of wheels

Don

I wouldn't chance wider tires on these rims. I just don't think they're designed for wider tires. Also remember your turning radius will be affected by the wider tires. The tires could rub the wheel wells at full lock.

A l-o-n-g time ago, I put a set of 185-width tires on a car that came with 155-width tires, with no ill effects, but I think the rim was designed to handle the wider tires.

These *should* work OK

http://www.ebay.com/itm/15-Honda-INSIGHT-Wheels-RIMS-Tires-10-12-OEM-EX-Hybrid-11-64004-FIT-CIVIC-/200908208610?pt=Motors_Car_Truck_Parts_Accessories&hash=item2ec70ff9e2&vxp=mtr

Not guaranteeing anything mind you, but it's probably the cheapest way to go . . . . .

Don

Thank you for the information on rim width versus tyre width.

Don,

The reference to those Honda wheels is helpful. I am just a bit confused, did we not have an issue regarding the front axel having very abnormal length not letting us mount the rear rims to the front.

I am sorry if my question is trivial, these wheel, ET numbers is one area I have never got to learn about cars.

Best
Nader

I've got the wheels off my car experimenting . . . . again! All of the following applies to iMiEV's with the factory SE alloy wheels - I don't know what differences there may be with the steel ES wheels, so I can't comment on those

First, those Insight wheels won't fit the front - At least, not without a bit of finagling. Honda uses a 56.1mm centerbore, which is the same as our wheels . . . . at least according to the 'book'
http://www.wheel-fitment.com/car/Mitsubishi/i-MiEV%20(2010%20-%20)/
True, our rear wheels ARE a 56.1mm centerbore, but the front of our car is the weirdest bird I've ever seen, in several ways. The important difference here is, we have the little aluminum 'collar' pressed into the front hub which prevents you from mounting the rear wheels on the front . . . . at least, I *thought* that was what it was for. In reality, it's just there to make sure you cannot get even one thread started if you're trying to mount a rear wheel on the front

I removed that ring last time I had the wheels off the car and put a Miata wheel on the front - 15's fit fine, 14's bolt on but the wheel doesn't clear the McPherson strut suspension . . . . but the Miata wheels have a larger centerbore, so I wasn't aware that a rear iMiEV wheel wouldn't fit with the little collar removed - I just assumed they would. Turns out, they won't . . . . read on

This time, for the first time, I removed the collar and tried a rear iMiEV alloy wheel on the front and it still won't go completely on. The machined part of the hub which the collar presses into is still larger than the 56.1mm centerbore of the rear wheel and it sticks out 3/16ths or so. If you bought a set of Insight wheels, it wouldn't take 5 minutes to grind that machined lip away and THEN any wheel with any centerbore would go on the front . . . . or, you could have the centerbore of the wheel machined out a bit and the wheels would fit with no modification to the car. The Insight wheels will fit the rear just fine - The centerbores are the same

Anyway, with the little collar removed it is possible to *almost* bolt a rear wheel on the front, just to check for fit, so I did that - It won't go completely on (you couldn't drive the car) because the lip won't let it go all the way flush with the hub. The rear wheel/tire clears everything up front (barely) so you could use the car with 4 equally sized tires, which is GREAT news! The crazy front end geometry does have the wider wheel sticking out a bit farther than the tiny 4 inch OEM front wheel does . . . . it's hard to tell exactly how much because the rear wheel wouldn't bolt on flush, but I'd say the front track width would change by a little more than an inch - perhaps 5/8th or so on either side. Not good

But . . . . Wheel offsets! Our wheels are 35mm and the Insight wheels are 45mm. This means that a Honda Insight wheel on the front would fit even better than an iMiEV rear wheel does. The 10mm of extra offset on the Honda wheel would negate much of that previously mentioned 5/8 inch, so the wheel would be tucked back closer inside like it belongs - Perfect!

On the rear, that extra 10mm would tuck the wheel back into the fenders more than our stock wheels, but that 'problem' would be easily solved by adding a 10mm spacer between the wheel and the hub. Because of the cars unusual suspension geometry, using 4 equal width wheels almost means the fronts and rears NEED TO BE wheels with different offsets. Using 4 of the 45mm offset Insight wheels (with 10mm spacers on the rear) means . . . . you could use 4 same sized wheels AND tires, so you would then be able to rotate your tires normally. Perfect!

I was about to buy the eBay wheels/tires, but the tires are not suitable. We would need either the stock 175/60-15 tires like our rear tires or, ideally, a matched set of 185/55-15's which gives us a fatter tire which still has the correct diameter and circumference. A slightly larger circumference tire would be OK, but it would A.) Change the rear gearing slightly which I don't think is advisable, and B.) There's barely enough fender clearance up front for the stock size. So, I think it's either the 175/60's or the 185/55's - Either is a HUGE improvement from the 145/65-15 we have up there now

Since I can't use the stock Insight tires, the eBay deal isn't so great. I need to find me a bare set of wheels, mount a set of 185/55-15's and THEN we'll see how it handles! 90% sure I'm going to do this, so I'll probably be the guinea pig if you guys can wait a spell

I prefer the look of the Insight wheels over our stock alloys anyway and I'm sure bigger front tires would improve the handling a bunch . . . . it won't make it a Miata by any means, but it will be lots more FUN to drive!

Don

[Edit] - Sorry the above link doesn't take you straight to the iMiEV wheel data, but it's there on that site and they say it is 56.1 and make no mention of the front being different . . . . but they ARE

Thanks for your experimentation, Don! I think that many of us will especially appreciate what you're doing when we need to replace our tires. Finding OEM-sized low-rolling-resistance (LRR) tires could be difficult in the future in the U.S. considering how few i-MiEV's are likely to have been sold.

It's not clear to me whether you consider the OEM rear tires to be suitable for the front. You seem to prefer the 185/55R15. Is that because you prefer as wide a tire as would fit? Have you been able to find a 185/55R15 LRR tire? For those of us who don't want to lose any range by changing to a different tire, it's important to find tires with the lowest rolling resistance even though we would have to sacrifice some handling in the process. We may lose a tiny bit of high-speed range due to the increased drag of wider front tires, but I that would be an acceptable trade-off to me to be able to use the same tires and wheels front and back.

Many thanks Don.

This is the way to go, modify the front hub and use spacers at the back in order to be able to rotate tires.

I will definitely go forward with such a solution even if officially it would not be homologated with the car but that would only cause an issue in case off an accident incriminating the car even if the new fitting would be batter.

Don't you think it is worth trying 16" wheels, price would be pretty much equal to 15" but handling would further improve.

Next we need to add strut bars :twisted:

This car only has struts in the front and their tops are so close to the forward bulkhead that adding a strut bar wouldn't do anything to stiffen up the front end. Cars with the engine bay in the front between the struts many times have the tops of the struts relatively unsupported, so adding a bar over the engine, across between the strut tops (even better if it's triangulated against the firewall) really stiffens up those cars and improves handling. A strut bar would do nothing at all that I can see for our cars

Don

Great work Don
Thanks for investigating and sharing your findings. It sure would be good to get our wheel options sorted out.

Maybe by the time we'll be needing new tires, Michelin's new EV tires will be available in North America, hopefully at a reasonable price, in an appropriate size for the i-MiEV.

While it is important to find a wheel/tire combination that doesn't change the effective gear ratio of the car, it's also important to me to keep the speedometer/odometer accurate. Does the speedometer run off the front or rear wheels?

I did even more playing around with the car this afternoon - I *thought* I had found a good solution. A set of four, 175/50-16's mounted on 2007 - 11 Honda Fit 16 x 6 alloys. The tires are within 1% of the correct diameter for the rear and should easily fit the front too, assuming the proper wheel. I even found me a *perfect* set of the Honda wheels for cheap - $330 plus shipping

So, before I pulled the trigger, I went back to measuring what *should* fit by mounting other 4 x 100 alloys I have laying around. Sad to say, There is no way any 6 inch wide wheel of suitable (or even unsuitable) offset will fit the front end of this car . . . . period!

I *think* the Rinspeed car is using 175/50-16's up front on 5.5 inch wheels, but we would need to know the offset they used. They don't stick out very far, so I'm guessing an offset in the 4o to 45mm range, but we would need to know exactly . . . . There is very, very little room for error on the front to clear the suspension - Nearly any wheel will fit the rear

I don't know of any car running around on stock 16 x 5.5 wheels, so doing this probably means a set of Work Wheels like they used on the Rinspeed car . . . . and that's going to mean about $2500 for new wheels and tires - A bit rich for my blood

Don

alohart said:

Maybe by the time we'll be needing new tires, Michelin's new EV tires will be available in North America, hopefully at a reasonable price, in an appropriate size for the i-MiEV.

Click to expand...

Tire Rack has the LRR Continental ContiEcoContact EP in stock in 145/65-15 and also in 175/55-15 . . . . but my car came with 175/60-15's on the rear

While it is important to find a wheel/tire combination that doesn't change the effective gear ratio of the car, it's also important to me to keep the speedometer/odometer accurate. Does the speedometer run off the front or rear wheels?

Click to expand...

I've been wondering about that too. I'm *assuming* the speedo is driven off the rear, since the computer is already aware of the motor RPM, along with nearly everything else happening back there - But . . . . it *could also be* taken from the ABS signal off of anyone of the 4 wheels - Hope not. More questions for Rinspeed if we ever get a contact with anyone there

Don

I have the name of someone there. Will try and find out these details. Apparently the seller of those works wheels told me that Rinspeed even has the homologation papers for those wheels...

Don, did you notice, the front wheels have a slight camber, maybe to avoid touching the body...

Will report back when I have the info.

Thank you.

Okay, since I've already committed heresy by proposing high voltage hacks, I hope Don won't mind commenting on the following. Big-n-Little setups with a smaller diameter wheel up front or a taller profile rear tire are a long-cherished hot rod feature. Other than looking funny and possibly throwing off the speedometer and stability control, what would be other impacts of mounting 13" wheels on the rear. (13" won't clear the front calipers)

For stock gearing, 165/80 13 would be only 0.5% fewer revs per mile, but should provide a softer rear ride.

For faster acceleration, 185/60-13 would increase revs/gear down by 6.6% and 175/5-130 would allow one to gear down by 14.5%!
That should decrease top speed from 82 to 70.11 mph, which could be considered "perfect" for most US driving.
It would reduce the rear ride height by 3.4", which would be enough to 'reverse the rake' of the car, and prompt one to lower the front or make some custom small rims for the front....

If the look is too odd it might even be disguisable with some creative wheel covers or porta-walls.
Such as this little startup that offers aero covers which attach to any wheel http://www.tuneko.com/TuneCover---Aluminium-wheel-hubcaps.php

Oh, I love all mods . . . . especially wheel/tire and suspension mods :lol: - No 'heresy' from me . . . . I just wanted you to think everything through before you bought a bunch of expensive parts

In a previous life, I was a real 'Corvair nut' - Specifically, the 140hp, 4 carb set-up on the '65 and '66 Corsas. I had one of each, both were convertibles. I lived in Tacoma (stationed at McCord) when I bought my first one

They came with 6.50-13 tires on 5.5 inch wheels on all 4 corners (which is even more of a travesty than the set-up on our I cars) so my first move there was to go to something which kept the stock circumference and put some extra meat on the rear, which any car with 60% of it's mass resting on the rear wheels really needs

I don't recall the exact sizes off the top of my head, but I think I used 205/55-15's on 7 inch wheels on the rear and 195/70-14's on 6 inch wheels up front. The wheels were stock Chevy Rally Wheels and I can't recall that anyone actually noticed they were different sizes. All dressed up with the stainless trim rings and centercaps, they looked positively stock! What a difference in handling THAT made! I have a picture, but no way to post it

So - I'm not at all opposed to differing wheels/tires front to rear, but I don't think I would go with 13 inch wheels and an ever narrower rear tire than we currently have. Our car is still a little rear heavy, so any solution which involves a little more meat on the rear probably isn't a bad idea. I've been considering using 14 inch wheels all around from the beginning . . . . and I happen to have a really lightweight (9 pounds) set of wheels at my disposal, since I recently upgraded my Miata wheels. The wheels I have are 6 inches wide and they will not *quite* go on the front (the wheel barely hits the front strut . . . . but clears the brakes just fine) so if I'm willing to cut 2 of the wheels down to a 5 inch width (not all that hard to do actually) I could go with 195/60-14's on the rear (about 1% smaller circumference than our stock 175/60-15's) on a 6 inch wheel and 175/65-14's on the front on a 5 inch wheel - I *think* this would probably be a great handling package . . . . . and I *LOVE* the look of the Miata basketweave BBS wheels - I made an 'adjustment' to the centerbore and mounted a set of the RX-7 15 x 6.5 inch wheels on my Protégé 5, replacing the 195/50-16's with 205/55-15's . . . . same overall circumference - You're right in that it improves the ride and the extra rubber did wonders for the handling as well

We'll see what comes to pass . . . . this isn't over yet

Don

Actually the contact I had in Rinspeed is actually the owner and CEO who unfortunately is away until the 10th April. I will write him an email once he is back to see if he would provide that information on the ET of these Alloy wheels.

Update:

Contacted the technical person in Mitsubishi who had those modified iMiev with him !

Hats off, excellent service compared to Citroen who had tried to void warranty for giving me a larger EVSE!

He promised to send the technical dimensions of the wheels and even more ask for an equivalence in order to have an official homologation certificate for a Czero!

That is what I call service. On my next purchase, I will certainly value and consider Mitsubishi !

Will update when I get the technical data.

Wow thx, Centaur- any input from Mitsu technical staff is valued, no matter how many caveats and qualifiers are attached!

Don, yes- I loved the BBS basket weave on my '95 M Ed. Miata. They were super light, and I even had one successfully straightened after a bad pothole... Corvair nuts are a special breed too. I've always wanted to meet someone with clolse knowledge of the Electrovair program. They made a few different Corvair EVs, including the Monza and the Van, I love this ramptruck conversion...(well, the concept more than the execution). http://www.evalbum.com/656
Only production more ready-made for EV might be an aircooled VW pickup. http://www.evalbum.com/115

1966 Electrovair II Concept
1966 GM Electrovair II Experimental Electric Car
http://history.gmheritagecenter.com/wiki/index.php/1966_Electrovair_II_Concept

I was there...

Tell us your story >

Written by Bill Bowman

The battery powered 1966 Electrovair II concept was a test bed for motor and control developments. Its power source was a silver zinc battery pack, in a 532-volt array, located in the front and rear compartments of a 1966 Corvair Monza sport sedan. Silver zinc batteries were used because they delivered high peak power and provided good energy storage but they were costly and were worn out after 100 recharges.

The battery pack was connected to a 115 horsepower AC-Induction motor that produced approximately the same performance as a conventional gasoline powered Corvair, except for its limited range of 40-80 miles before recharging. A tank full of gasoline would propel a Corvair 250-300 miles. Top speed was 80 m.p.h.

Electrovair II’s total weight was approximately 800 lbs. more than a Corvair, even with the comparatively light and compact silver zinc battery pack. If it were propelled by conventional lead acid batteries, the batteries alone would weigh more than 2,600 lbs., approximately the total weight of a standard Corvair.

Some of the touches that set the Electrovair dash apart from the production car are large gages for monitoring volts and amps occupy the space normally reserved for the radio and the in-dash gear selector has no “L” for low.

I got the info we are looking for, many thanks to Mitsubishi Switzerland !

Front: Tyre 175/50/16 Wheel 16"/5.5"/ET 34
Back : Tyre 195/45/16 Wheel 16"/6.5"/ET 33

Make Work Japan, model schwert SC1 (SW1)

For reference, the original sizes on EU model are:

Front: 145/65 R15 72S Wheel: 4.00x15 ET35
Back: 175/55 R15 77S Wheel: 5.00X15 ET35

Thanks
Nader