Ke70 With 17's- Who's Done It?

[twisted2]

+1 for 15's i run meshes with 205 50 15 and they fill guards nice and those advan tri spokes look tuff but dish is what makes a rim

[LXY-642]

Love 3 spokes with dish :laff:

[nickyboy]

I think the max you can go legally is 2" bigger than what is stock. If your car was factory fitted with 15"s then you could have 17"s legally.

I don't mind it, at least you can still get over speed humps and have the guards on the tires :laff:

 

no ke70 is fitted with factory 15s.

[LXY-642]

Pretty sure he was just pointing out that if 2" bigger is the law then you need to have 15" wheels from factory. Not saying that ke70's came with 15's from factory.

 

In Victoria and act it goes by overall rolling diameter. With no more then 15mm overall difference. For example the 16's I had on my old ke36 were still legal being 205/40/16. From the factory 13's. And on my old white vl I had 20's from the 15's 205/65/15 to 225/30/20. The 20's were actually slightly smaller rolling diameter.

 

 

Also in a post a few back turning a larger rolling diameter slowing down a car? Lol that's funny. What's actually happening is you would be travelling further for each rotation for the wheel turning. So therfore you would actually be going faster. A smaller overall diameter would mean less distance for each rotation of the wheel resulting in slower. But regardless it's not going to be an amount that you would notice in normall street driving. Tyre sizing plays a major role in drag racing however using the tyre sizing along with diff gears and gear ratios to work out what will work best. With vl's and 3.45:1 diff gears they normally go for it was either a 26x10 or 28x10 on a 15 works ideally different diff gears would use different tyre size.

 

Google miata tyre calculator and the first one to come up is quite good. You put in factory tyre size then new tyre size and it will tell you all the info in the differences from overall diameter to how much you'd be driving sitting on 100 compared to factory size.

 

Matt

[LittleRedSpirit]

Also in a post a few back turning a larger rolling diameter slowing down a car? Lol that's funny. What's actually happening is you would be travelling further for each rotation for the wheel turning. So therfore you would actually be going faster. A smaller overall diameter would mean less distance for each rotation of the wheel resulting in slower. But regardless it's not going to be an amount that you would notice in normall street driving. Tyre sizing plays a major role in drag racing however using the tyre sizing along with diff gears and gear ratios to work out what will work best. With vl's and 3.45:1 diff gears they normally go for it was either a 26x10 or 28x10 on a 15 works ideally different diff gears would use different tyre size.

 

Google miata tyre calculator and the first one to come up is quite good. You put in factory tyre size then new tyre size and it will tell you all the info in the differences from overall diameter to how much you'd be driving sitting on 100 compared to factory size.

 

Matt

 

 

Might want to check your facts and assumptions there.

 

If the mass of both vehicles is the same, and the same amount of power is used to rotate the axle, the car with the smaller rolling diameter will accellerate faster (assumng everything else is the same). Its the same effect as going from a tall diff gear to a lower ratio.

 

If you could explain where the magical extra power comes from to turn the axle I'd be really keen to find out.

 

You will have a higher theoretical top speed with a taller diff ratio (which is what your google buddy calculators are telling you), but you will get there slower. You need to strike a balance to achieve the best result for your application. For example, a lot of people with 4 speed street driven dailys may opt for a slightly taller diff ratio to take some burden off of the engine and slow its rpm at 100klm/hr. This will increase fuel economy, and slow the possible accelaration. Tha same car being set up for drag will have a fairly short ratio by comparison to maximise acceleration so that the car hits its top speed after no more than 395m if possible.

Edited April 24, 2010 by LittleRedSpirit

[LXY-642]

ATM I can't really be bothered thinking to much or looking into it further lol. But from my understanding. If nothing else has changed then your diff will still be turning exactly the same and if your overall diameter of your tyres is larger then you would clearly be travelling a further distance for each rotation of the wheel.

 

This has actually got me very interested. When I can be bothered I'll be looking into and searching as much as I can as this would be handy info to know.

 

But from experiance changing tyre rolling diameter is not really something that you will notice in a normal everyday driven car.

[Jason]

There is not much to actually 'know'.

 

Smaller rolling diameter = better acceleration, lower top speed

Bigger rolling diameter = lower acceleration, high top speed

 

There is never a win win situation in engineering, always a compromise.

[agius]

There is not much to actually 'know'.

 

Smaller rolling diameter = better acceleration, lower top speed

Bigger rolling diameter = lower acceleration, high top speed

 

There is never a win win situation in engineering, always a compromise.

 

dittto to that!

[LXY-642]

Oh well. So therfore I am right in saying that you will travel further for each rotation of the wheel. And little red spirit is right in that it will be slower to accelerate. But if your sticking withing the 15mm overall diameter ruling then I doubt you'd ever notice any difference in driving.

 

 

I'll be going with either 16's or 17's on my purple wagon. But it will only be because that i will be running bigger brakes to need the bigger brakes.

[Jason]

I ran 14inch wheels with the Landcruiser calipers... Unless your running a willwood kit.

 

Btw my thoughts on bigger wheels, less tyre wall, less slip angle, which means less feel at the limit.

[LittleRedSpirit]

Oh well. So therfore I am right in saying that you will travel further for each rotation of the wheel. And little red spirit is right in that it will be slower to accelerate. But if your sticking withing the 15mm overall diameter ruling then I doubt you'd ever notice any difference in driving.

 

 

I'll be going with either 16's or 17's on my purple wagon. But it will only be because that i will be running bigger brakes to need the bigger brakes.

 

 

 

I stated exactly that in my post above, to which you disagreed. Nobody (except you) seems to care if you are right or wrong, just accept the information and don't try to make personal excuses, its undignified. We are all here to learn and all wrong and right at different times. Its a good opportunity for you to wrap your head around it instead of saying (allow me to paraphrase) "I may be wrong but I might give it some thought later". Just read it, think about it and learn it. Its dead simple, and its better to think about something and understand it before you go correcting people. Opinions are a different matter entirely, as they are not governed by the laws of the physical world. This concept is.

 

So you will run 320mm rotors that actually require 17s? Most corolla relevant brake upgrades are able to fit in 14s or 15s. (and will still look a bit odd in a 16 or 17).

 

Yes you feel a large difference in driving with a large rolling diameter.

 

1. slowness.

2. smoothness.

3. lower rpm at a given speed limit, might even get to use a different gear in some situations.

 

Its quite a good dynamic change for certain applications. It will also raise the vehicle of course.

Edited April 24, 2010 by LittleRedSpirit

[mungi mods]

i ran 185/60/13 onmy ke andat 100 km/h it was revving at 3400 rpm

swapping toa 15 with a 195/50 revs dropped to 3200 rpm at 100

going to a 205/50/16 on a 16 x 8 dropped revs to 3000 rpm

all speeds were done via a gps..

so you can see that there is a 400 rpm difference between 13 and 16 in rims/tyres

biggest problem with a 17 inch rim on a ke is the way the inner guards are designed

it is possible to run them but the car will be high off the ground and the "flare" section does not cope with the increased diameter

 

as for brake upgrade , in the end the braking performance is only as good as the tyres grip.

 

.

[oh what a nissan feeling!]

Yep, I have 300mm brakes on mine, they fit inside any 15.

 

Specification Sidewall Radius Diameter Circumference Revs/Mile

 

185/60-13 4.4in 10.9in 21.7in 68.3in 928

 

195/50-15 3.8in 11.3in 22.7in 71.2in 889

 

205/50-16 4.0in 12.0in 24.1in 75.6in 838

 

205/40-17 3.2in 11.7in 23.5in 73.7in 860

 

I just went out to the shed, the 17s are the size tyre i run on all of my 17s,

 

so the 17s would actually have the car sitting lower than the aforementioned 16s, as the 17s have a smaller rolling diameter.

[twinspinna]

my opinion 17s looks the goods. and you can still go low (NZ lowness) ,with them and not scrub. just gotta get offsets right.

ride wont be that smooth but apperance is staunch.

get a good tyre combination with 17s and nothing will noticeablly change ( speedo wise and acceleration etc) because the overall circumference wont change with a super low profile tyre. its physics..

13" is all good to tho. id love to own sum hotwires on my rolla but 17s are my pick.

 

check this out..

 

http://www.rotahavik.co.nz/viewtopic.php?f=25&t=25774

[Trev]

I think KROPLN ruined the image of 17's on E7's