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16's or 17's? need ppls thoughts!


Guest ON3GO

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Guest Big Phil

Some of the best handling car in the world run 17 and 18 inch tires. The new Mitsubishi EVO and and Subuaru WRX STI both achieved over .95 g on the skid pad and both come with 17 inch wheels. Also corvette Z06, Vipers, Porsches and BMW M3 all run larger than 17 inch wheels and no one complains about their acceleration or handling.

 

In fact try to think of a new ultra high performance vehicle that isn't sitting on a least a 17 inch tire. As long as you run a good tire with at least a 40 series aspect rear tire, I don't think handling or acceleration will suffer.

 

PS: A 275 40 17 (25.7 inch diameter) is taller than a 225 45 17 (25.1 inch diameter). A 275 50 17 rear (at least 26.3 inch diameter) would be WAY taller than the front. Most sports car use a smaller rear aspect in the rear the balance the height when the rear rims or wider. Look at the BMW M cars, Mercedes AMG cars, porsche or ferraris.

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Guest Big Phil

I saw that chart before I bought my tires and the buyer reviews are about equal. I went to a SCCA race event and ask several racers and they seemed to prefer the Kumhos. I honestly don't think you can go wrong with the Yokohama ES100 or the Kumho Esta MX.

 

I just think 17 inch rims look better and still offer good handling. Just don't get some heavy cast aluminium wheel. The weight of the rim effects your handle and acceleration as much as the type of tire. My 17 inch rims weight less 17 pounds a piece (less than the 17X8.5 Kinesis K5). Several companies make light rims. Below is a link to rim weights.

 

http://www.europeanspeed.com/wheelweights.htm

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Guest ON3GO

thanks for the info.

im not sure what tires ill go with. either one looks like ill be happy with.

oh BTW your car is very nice. love what you have done with it.

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Some of the best handling car in the world run 17 and 18 inch tires. The new Mitsubishi EVO and and Subuaru WRX STI both achieved over .95 g on the skid pad and both come with 17 inch wheels. Also corvette Z06, Vipers, Porsches and BMW M3 all run larger than 17 inch wheels and no one complains about their acceleration or handling.

Yup, you are correct. Hope you also noticed that you listed all 21st century cars with suspensions designed to work with such wheels/tires. The Z, OTOH, was designed in the 60s for 175/70-14s.

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Guest Big Phil

Scottie,

You make an interesting point, new rides are designed to operate on heavier rims and tires. I think what screws up handling is the weight not the size. Heavy rims hampers the ability of a vehicle's suspension to quickly react to bumps. The Zcar suspension was engineered to work on a vehicle of a specific weight with a specific amount of unsprung weight (total weight of rim, tire, brake rotor, etc)

 

Heavy rims also reduce acceleration and increase braking distance. Bigger rim usually weigh more than smaller ones. The average 17 inch rim weight 20-27 pounds while the stock 14 inch Z car rim weighed around 16-17 pounds. (see rim weight chart in prevoius post).

I bet your ride would improved if you went to a lighter 17 inch rim.

 

Here is some interesting info I grabbed off a website.

 

Bigger is Not Always Better:

As wheel and tire sizes increase, so does wheel and tire weight. This can have a drastic effect on the performance of low horsepower cars like the 510, even if the wider wheel and tire do give you more stick. As a general rule, you want to keep your rotating mass to a minimum (when I raced bicycles, we used to say that an saving an ounce on the wheels was like taking a pound off the bicycle frame). The inertia to get these rotating masses (called wheels and tires) moving can be compared to having a heavy or a light flywheel attached to the motor in your 510. A heavy flywheel is harder to get up to speed, not to mention harder to slow down. Specifically, you not only want to keep the total rotating mass down, but you want to keep the mass you have as near the center of the wheel as possible. Given the choice between two wheels of equal weight, the wheel with less rim mass will perform better, but the rim might also be more susceptible to pothole damage. Tires, since they surround the entire wheel, are an even more important place to shed weight. Same-size tires can vary significantly in weight by brand. A Hoosier radial race tire weighs 11 lbs, while their BFG counterparts in the same size weigh 18 lbs each. When choosing your wheels and tires, keep your eye on the scales. Don't believe hearsay wheel weights. I have tried to post accurate wheel weights in the wheel chart, but you really need to weigh the wheels and tires yourself. Many aftermarket aluminum alloy wheels weigh more than their stock steel counterparts in the same size!

 

In a September 1998 Sport Compact Car Magazine article, the authors changed their Honda Civic Si from stock 14" steel wheels to new 17" alloy monsters, but reported that the car lost some of its zip. The stock wheel/tire combination weighed 34 lbs, while their 17" O.Z. wheels and Nitto tire combination weighed in at 43 lbs each. When they put the car on the dyno with the stock wheels, they saw 113.5 peak real wheel horsepower. With the 17" combo and NO OTHER CHANGES, they saw 107.9 peak real wheel horsepower, a drop of 5.6 hp just from using larger and heavier wheels which "only" added a total of 36 lbs to the car's 2000+ lb curb weight. Now you know why my D street-prepared autocross 510 runs on 13" wheels with 185/60-13 tires!

 

If a 16/17 inch rim combo weighs the exact same as the 14 inch factory combo, handling should not be adversely affected. If they have the same overall diameter acceleration also shouldn't be affected.

 

Excessive lowering also affects handling. The main reason most people lower their ride excessively is to fill the wheel. A larger rim will fill the wheel well without having to over lower the ride. The result is good looks with good handling.

 

Note: You may have to change the gearing if the overall wheel/tire diameter is taller than stock to maintain your acceleration.

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IMO go 16sw if you can find the tires you want for them. I have 17s on my car and it raised the overall ground clearance. 2454517s in the back and I don't think I could easily have gone wider without some spacers. I'm running the Konig 5.0s for the Mustang with two different offsets. There are some posts here with pics and measurements somewhere as well as some info on my site. I sorta' wish I'd kept the old style Panasports I'd had when I got the car but they were 4lug...

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Some of the best handling car in the world run 17 and 18 inch tires.

 

While wheel/tire weight is a big issue, SCC, Grassroots Motorsports, et. al. miss the reason that older vehicles generally handle worse with lower profile tires - shocks.

 

A tire is just another spring in the suspension with a rate of 1,000 to 1,500 lb. in. depending (mostly) on inflation pressures. That sounds like a huge rate but tires respond much quicker then the suspension can. If you elimiate some of that response via higher air pressures (required for shorter sidewalls) you have to get back some of that response in the only other place possible, bump and rebound damping. If you don't get that response back, you get a car that tends to skate. (BTW... that's why your car will always stick better with the lowest air pressures you can run without "rolling over.")

 

Modern performance vehicle shocks are designed with more compliance in bump and control in rebound. The shocks can respond better and provide the compliance necessary to make ultra low profiles work.

 

Unfortunately for us older car owners, we're stuck with 1970's shock technology even when we purchase Tokico Illuminas, Bilstiens, etc. designed for our cars. The shock designers rely on the tires to provide the responce and compliance and build their shocks with too much bump and not enough rebound.

 

Now, if you had, say, a set of Penske 8760 triple adjustbale shocks on your 240Z...

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Guest zline

those wheels also have super high offsets...

 

I'd just go with a set of Hayashi Racing CRs in 15x8 all around with zero offset.

 

or some SSR Formula Mesh 15x7.5 f 15x8 r +1 offset for both.

 

The best thing is to run a small tire over a wide wheel, ie., 205/55/15 RE750 on the Hayashi CRs

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Guest ON3GO

well im going for 16's i guess.

going with the yokohama AVS ES100's in a 245/45/16 in the rear and a 225/45/16 in the front. will be under 25ins total.

should look and hook good, if not i can always use drag radails.

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