Anybody run a 225/55-16 245/50-16 combo?

[jonbot]

I just purchased a set of 8x9x16" Fuchs and I'm in the process of trying to find the right tire combination for them. I noticed the popular combo seems to be 225/50-16 front and 245/45-16 rear. I was about to run this combination, until someone posted a link to this tool:

http://www.wheelsmaster.com/rt_specs.jsp

I've found that a combo of 225/55-16 for the fronts and 245/50-16 for the back yields a much much wider selection from tirerack.com (21 choices), and also brings the front and rear tire diameters within a 2mm spec of each other.

Would I experience any adverse effects of running this tire combo in regards to ride quality, interference, scrub radius, or anything else I'm not thinking of?

[richde]

Front would be too tall. 205/55/16 is normal, a 225/50 would fit better, and you've probably got to dial in some good camber/seriously roll your fenders not to rub.

[rusnak]

I have a rubbing issue with 205/55s in the front on 7s. If you have your old tires, you can re-mount your 205s on your old 7 inchers while you decide what to do with the 8s.

btw I think the issue with respect to tire availability is the 9"x16" rears. Lots of choices on 205/55/16s, not much on 245/45/16s. I think 245/50/16s might look and drive like a truck tire. just my $.02

[jonbot]

Originally Posted by richde

Front would be too tall. 205/55/16 is normal, a 225/50 would fit better, and you've probably got to dial in some good camber/seriously roll your fenders not to rub.

My car has turbo flares, would I still have these issues?

[jonbot]

Originally Posted by rusnak

I have a rubbing issue with 205/55s in the front on 7s. If you have your old tires, you can re-mount your 205s on your old 7 inchers while you decide what to do with the 8s.

btw I think the issue with respect to tire availability is the 9"x16" rears. Lots of choices on 205/55/16s, not much on 245/45/16s. I think 245/50/16s might look and drive like a truck tire. just my $.02

I see, so the real problem is availability of the rears. I don't know about the "truck look/feel" thing, that website says it will only be one inch taller diameter, meaning 1/2" more of sidewall all the way around. It doesn't sound like much, but maybe once it's mounted it looks funny.

I'm kinda bummed about the tire selection, at least there are some good choices, but no all-season tires available, only summer tires. I was also leaning towards the 225/55 - 16 fronts and 245/50 - 16 rears because if I go for the 225/50-16 front 245/45-16 rear, the rears will be about a 1/4" shorter than the fronts, which just seems odd to me.

[rusnak]

Jon,

you are in good company being bummed out about the tire selection.

I think you should talk to the tirerack people about the tire sidewall ratios you are contemplating.

If you have turbo flares, then you can go wider for sure, but I will remain silent since I have no direct experience on this.

I also noticed that you are in the bay area, calif. I really don't think you need an all season (read snow) tire. I have Bridgestone RE750s and before that had S-03s and S-02s. Only the Dunlops and Yokohama AVS Intermediates in my experience made a poor choice in the winter. The Brigestones are ok for everything except snow. And if it's snowing, I ain't gonna drive the Porsche anyway.....

[Bill Verburg]

If I were you I would be thinking 225/45 and 245/45.

I just don't understand this availability issue, it's croping up in all sizes 15 - 19.

I suspect that the tires folks just don't make enough profit on the rarer sizes.

[porsche930dude]

i run 225/50 and 245/50 on turbo flares. Oz wheels so i cant comment on rimsize or offset but its lowered and works nicely

[Bill Verburg]

The issue w/ 245/50 vs 245/45 rears is that the additional height of the rears kills acceleration through the gears. Now if you are trying to maximize time in a particular gear for a particular track that may be useful, but for most, not.

[ENTHUZD]

225 in the front rubs... tried it

[Bill Verburg]

Originally Posted by ENTHUZD

225 in the front rubs... tried it

All cars are different, idiosyncratic setup is also an issue.

225/45 vs 225/50 gives you a lot of breathing room. Not so necessary w/ 930 fenders but still nice to have.

[porsche930dude]

Originally Posted by Bill Verburg

The issue w/ 245/50 vs 245/45 rears is that the additional height of the rears kills acceleration through the gears. Now if you are trying to maximize time in a particular gear for a particular track that may be useful, but for most, not.

according to the miata tire size calculator the 45 is a half inch smaller and the 50 is a half inch bigger than the stock size. Thats stock for my 82 sc anyway. I went from 45s to 50,s and saw no major difference

[Bill Verburg]

Originally Posted by porsche930dude

according to the miata tire size calculator the 45 is a half inch smaller and the 50 is a half inch bigger than the stock size. Thats stock for my 82 sc anyway. I went from 45s to 50,s and saw no major difference

here's something I did when I was loking a some different 17s

PHP Code:

So3    rim    cs    on 8&9.5    tread    height    slr    rpm    wt
225/45x17    7.5     9.00      9.20     8.4    25.00    11.60    833    25
235/45    8.0     9.40      9.40     8.7    25.30    11.70    823    27
235/40    8.5     9.70         8.5    24.50    11.40    850    24
265/40    9.5     10.90      10.90     9.7    25.30    11.70    823    29
255/40    9.0     10.40         9.4    25.10    11.60    830    27
                                
SP-9000                                
235/45x17    8.0     9.40      9.40     8.5    25.50    11.90    826    24.5
275/40    9.5     11.00      11.00     9.9    25.70    11.90    816    29.1
235/40    8.5     9.40         8.2    24.50    11.50    859    22.1
255/40    9.0     10.40         9.0    25.00    11.70    839    25.6
265/40    9.5     10.70      10.70     9.0    25.40    11.80    819    23.2
                                
Piliot Sport Cup                                
225/45x17    7.5     8.90      9.10         25.10        835    
255/40    9.0     10.70      10.90         25.20        831    
                                
Pilot Sport                                
235/40x17    8.5    9.4    9.2        24.4        849    
265/35    9.5    10.7    10.7        24.3        856    
                                
PS2                                
235/45    8    9.3            25.4        820    21
235/40    8.5    9.5            24.4        852    
265/40    10    10.7            25.3        822    28
                                
Hoosier DOT radials                                
225/45x17    7.5     9.50         8.8    24.60            17
245/45    8.0     9.80         9.3    25.30            
245/40    8.5     10.50         9.2    24.50            20
275/40    9.5     11.10         10.3    25.30            
                                
Goodyear F1 GSCS                                
245/45x17    8.5     9.90     9.7    8.6    25.68            
265/40    9.5     10.70     10.7    8.8    25.50            

Toyo T1R                                
235/45ZR17    8    9.4            25.4    11.8    811    
235/40x17    8.5    9.5            24.4    11.4    853    
265/40x17    9.5    10.6            25.3    11.7    821    

Toyo RA1                                
225/50x16    7    9.5        9.25    24.5    12.1875        
245/45x16    9    10.5        10.25    24.25    12.1875        
                                
Kumho MX                                
225/45x17    7.5    8.875            25            43.5KinSC
275/40x17    9    10.375            25.625            49.5KinSC 


all tires are a little bit different in width, height and profile. The dimensions also change depending on the wheel width that they are mounted on.

[Richard Burns]

If you have A/c I would be worried about the offset of the rears to avoid rubbing against the A/c tubes taht are in the wheel well.

[jonbot]

Rusnak: It's not so much the width I'm worried about as it seems everybody and their mother goes with at least 9" wheels on the back, and it's been shown time and again 8" will work in the front with the turbo flares, it's the height I was worried about. I will contact tirerack as you suggest and see what information I can squeeze from them. Also, I went to my local wheel shop and he confirmed what you say about the season tires. He suggests I run summer tires as some of the all season tires develop "cupping" over time. He said you almost can't go wrong with tires nowadays, they're all pretty good.

Bill: Interesting note about that 225/45 / 245/45 setup you recommend, I haven't heard of that before.

Porsche930Dude: Are those pics on your myspace page with that same tire setup? Doesn't look bad at all

Richard Burns: I do have A/C, but I'm sure I'll be running at least a 1" spacer in the rear, and possibly a 1/2" spacer in the front, I'll wait till the tires are mounted to see what it looks like.
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If you guys haven't yet, you should check out that tire size calculator (probably similar to that miata one) in this link:

http://www.wheelsmaster.com/rt_specs.jsp

It's pretty sweet!

[porsche930dude]

Those pics are with the 45s the 50s were about an inch bigger overall which actually looks even better

[Bill Verburg]

Bill: Interesting note about that 225/45 / 245/45 setup you recommend, I haven't heard of that before.

It's more common for the narrow body cars, where it is used for clearance, but the shorter sidwall also gives quicker turn in for the front and gets the front end lower(always a good thing)

[jonbot]

Porsche930Dude, can you take a pic or two when you get a chance?

[JeremyD]

I run 225/45/16 and 245/45 16

the 45 to 50 really makes a big difference

[porsche930dude]

The new 50s are actually skinnier than the old 45s so there a bit more bulgey on the sidewall. First pic is the 45s dunlops and second is the 50s bfg. But its like bill said all manufacturers have there different specs