different wheel question

CitizenErazed

Torque Junkie
Points
0
Car
1.4 Tigra MK1
Nothing to do with my confusion about speed changed last week.

Ok so it turns out my wheels are currently 15" not 16, my mistake, looking to increase size still though, but the problem is comeing down to tyre sizes, i've been looking at it all night and working it out and worked out that for my car if I go for a 16" alloy I will need a 185/50 R16 H and if I go for a 17" which I would prefer to do I will need a 185/45 R17 H. (I can't have more then a 185 width on my car without flareing the arches.

Thing is whilst I've seen that these tyres exsist theoretically online I can't actually find the tyres themselves. On top of that I will need alloy wheels that these tyres fit to. By that I mean an alloy with a 185 width (I can't get more then that else it will stick out, less and the tyre wont fit) but when I look at alloy wheels it doesn't tell me what it's width is, only if it's a 15 16 17 " or whatever, so I don't actually know what width they are.

Does anyone know of some good wheels and tyres of these sizes? I can't seem to find any. 4 stud fitment, preferably gold BTW.

EDIT: Don't suppose a mod could edit my typo in the title could they? *blush* thanks :)
 
dont worry about colour, you can get them painted or powder coated.

if you find wheel and tyre packages with the correct size tyres then you dont need to worry anout the width as these should be the correct size.

think it might be 6 - 6.5" your looking for without streeeching but someone else should be able to confirm
 
So far I can't find any 16 or 17" alloys smaller then a 7" width :(

would 6.5" be okay on my car if I can't get wider then 185 or will I need a 6"? I'm not posative on how it crosses over.

I was orriginally looking at team dynamics monza or pro race series, but these are too wide it seems:(

Oh and cheers HDI! :)
 
17" is too big, in terms of rolling radius and weight. Can't always have performance AND looks I'm afraid. As for tyres, a 50 profile is too big too imo, a smaller profile will look better and have less flex in the sidewall.

The width is usually denoted by a number and a "J", ie 6J is 6 inches wide I think although I've never actually bothered to check. 185 will fit a 6J wheel with a bit of stretch, but 195 is the smallest "proper" fit.

Sounds a little strange nothing wider than 185 will fit though tbh. Could always get the arches rolled?
 
CLICKY SUNSHINE

Compomotive TH2 or MO FTW IMO!!! Although, the Monzas are on the last page. The site says they fit your car, but I'd ring up jsut to check. Once you've found the wheel and size you want, look elsewhere though - that websites a bit on the expensive side!!
 
17" is too big, in terms of rolling radius and weight. Can't always have performance AND looks I'm afraid. As for tyres, a 50 profile is too big too imo, a smaller profile will look better and have less flex in the sidewall.

The width is usually denoted by a number and a "J", ie 6J is 6 inches wide I think although I've never actually bothered to check. 185 will fit a 6J wheel with a bit of stretch, but 195 is the smallest "proper" fit.

Sounds a little strange nothing wider than 185 will fit though tbh. Could always get the arches rolled?


I'm not too botherd about the look TBH the reason I wanted 17" was so I could fit much bigger brakes onto the car, it was a handeling performance mod, not a power one though. If 50 is too big and I need to go down to 45 then I will have to get 17" because 45 on a 16" will mean I will have to get my car re-calibrated. 45 on a 17" and 50 on a 16" keeps the overall size within a tolerable percentage of my current overall size. On that basis aswell surely my rolling radious wont be changed? (well, marginally, but I've got it to within a tolerable percentage)

I've said 185 because thats what I currently have and the tyres are plush to the car, not much room on the inside of them either so any bigger and I will be sticking out, really don't want to flare/ roll the arches though.
 
thanks for the links but the problem isn't finding 16 or 17" alloys, it's finding them without them being too wide for the car, the 17" tend to start with a 205 size minimum and the 16's with 195.

It's strange though that when you put in tigra on that site it comes up with those wheels, looking at my car it looks like the 185's barely fit on as it is, I really don't think I can go any wider without makeing the arches wider :s
 
All that just hurt my brain. I'm so tired I can't think straight let alone calculate rolling radi. Most four-pot calipers and suitable discs will fit under most 16's. I'm currently in discussions over bracket designs to fit 4-pots under my 15" compomotive THs.

That site states that 7J will be fine on your car. It depends on the offset very very muchly too remember. My advice would be to go to your nearest alloy wheel centre, see what they have in stock and try a wheel on.
 
:lol: I appologise for the headache :)

Yeh, I don't understand why the sites are saying that, like I said it looks as though the 185's barely fit on as it is, maybee I'm wrong though, think I should ring up a specialist and check to be on the safe side, if 7J is fine then whoop! :D no worries, hope it is though, as it doesn't look like it would be :confused:

showing my ignorance here but, the offset?
 
iirc offset is the distance from the hub of the wheel to the centre of the wheel

varing the offset can mean you can fit wider wheels. but however it can mean that you have clearance issues with the brake callipers
 
Ahh I understand now, still there doesn't seem to be any room on the inside of my wheel either to pull it in *shrugs* I may be wrong about the widths, I'll ring bush tyres tomorrow and check. wider wheels would be a good bonous anyway, handeling improvements where I hadn't even planned it :lol:

From what the end of that article said: 'Straying too far from the original offset can be detremental as fouling to the suspension and bodywork can occur as well as eccess strain on wheel bolts or studs' I don't think I will want to tamper with my offset 'too' much.

Cheers guys :D
 
You really want to keep the offset, overall rolling diameter and ride height as close to standard as possible unless you plan significant other alterations.
 
offset and overall rolling diameter I'm trying to keep close to standerd.

Ride height, I will be getting coilovers and lowering my car at a later date.
 
mmm if your struggling with the bigger/wider wheels then your going to be srewed when it comes to lowering without getting the arches flared out.
 
bigger isn't a problem, I could probably fit 19" or so without too much of a problem so plenty of lowering room, esspecially when I'm keeping my overall diameter the same so will effectivly have the same overall size as a 15" wheel and standerd tyres, thing I need to work out with lowering is the average height of speedbumps sort of thing.

Lowering the car shouldn't effect my problems with the wheels width should it? How would that work?
 
the arch curves in the further up you go.
when you lower the car the wheel is sitting further up in the arch meaning you have less to work with.

again talking from the bora side i can fit narrow 19" (225 tyres) without to much problem however you cant lower it without sorting the arches. with the 17" i could therotically lower it without a problem. i say in theroy as work as some big as bumps that i can just squeeze over
 
That makes sense, I'll ring up bush tomorrow and see what J size I can fit at the moment, then ask what play that leaves me with for possible lowering
 
It would be easier,

getting your suspension and brakes sorted first, then getting the wheel/tyre combination done to suit how you want the car once the ride height and suspension are all sorted.

As for example, if you are going coil-overs this will allow more negative offset in any given wheel as it will not have the same clearance issues that you will have with a macpherson strut. These usually cause problems between the inside of the tyre and the strut spring seat cup.
Coil-overs have much smaller diameter springs, you won't have this issue.

Besides once all done it's easy enough going to a salvage yard and getting a few fwd wheels/tyres from say a Vectra or other fwd car with the same PCD and similar offset and be able to fit them up to experiment yourself.
I did similar things with an Astra and ended up with a full set of Cavalier GSi alloys and tyres for relatively small outlay and they caused no dramas at all.

Doing it this way is going to make things more difficult for you and you may not get the wheel/tyre combination right.

With any radial tyre the wheel section width should be within 10% of the tyre section width.

GM parts from higher spec Astras and Vectras are your easiest source of validated and proven parts that will fit straight onto your lower spec GM model with the minimum of hassle.
 
Last edited:
I know that the J is rim width in inches. What does the J stand for please?

The letter that typically sits between the rim width and diameter figures stamped on the wheel, and indicates the physical shape of the wheel where the tire bead meets it.
Hope this helps buddy. :bigsmile:
 
that carbibles site was a brilliant help to my understanding, thanks

As far as getting the suspension set up done first, I think it probably is the better idea, but I've been planning for so long I'm just itching to actually buy something and put something on the car, I told people months ago I was getting new alloys and brakes/ lowering etc.. and still nothings been done yet, it's getting kinda embaressing, like I'm all talk if yah get me.

If I leave room to play with in the width for lowering then I should be ok I think, I'm not lowering too much anyway as it's not that high as it is.
 
Okay,

That is your opinion and you are entitled to it.
Ask people who understand the consequences of going to a wider section tyre, or wheel and tyre combination on the front of a car and they will tell you it will increase the propensity to tram-line on the road, most times degrade the steering feel, cause the car to start aqua-planing at a lower speed, cause im-balance/vibration issues more easily, make it more difficult to drive in snow and ice conditions to name just a few.

The positives are it should allow more lateral g on any given corner and decrease braking distances. There are other positives but that generally has to do with off-roading. :)

I don't understand this really. Wider front wheels should mean more grip IMO. My Focus has standard wheels and tyre's and that does the Tram line thing as you point out so I don't think that a wide wheel issue I think it is a setup issue. And if correct all weather tyre's was fitted and in good condition it shouldn't aqua-plain any more than normal?
 
when I said 'tollerable percentage' what I ment is the differance in size ment that when my spedo read 70 I would actually be travelling at 71.something MPH, so perfectly livable. Bassically, i just didn't want to have to re-configure my car to the new rolling radius. I'd be quite happy to fit a wider tyre but it's dependant on weather it will fit
 
I don't understand this really. Wider front wheels should mean more grip IMO. My Focus has standard wheels and tyre's and that does the Tram line thing as you point out so I don't think that a wide wheel issue I think it is a setup issue. And if correct all weather tyre's was fitted and in good condition it shouldn't aqua-plain any more than normal?

Agreed, yes,

As mentioned wider tyres/wheels give a bigger contact patch, hence more grip.

Tramlining is subjective. Sometimes changing to a different brand of tyre and staying the same section width can change the effect. Some tyres (usually pattern design) are more susceptable to it than others.


For "MasterAuron"........

But with same brand of tyre and going up in section width will usually increase the chances of tramlining simply because the wider section is contacting more of the road surface and so is affected by cross-section camber changes in the road surface to a greater degree. This assumes same toe, castor and camber suspension settings.

Do a search on the subject and see for yourself, don't take my opinion as gospel. I learnt the long hard way and I'm not here as a convert.

Fitting wider wheels and tyres means a greater increase in total weight on each wheel station. This means more power is lost turning the wheel combo now, more aerodynamic drag, more rolling resistance too and a greater degree of balancing is needed for for this extra rotating mass to stay vibration-free. If there is an imbalance (say a wheel weight is lost; the vibration will be of relatively greater magnitude because a heavier mass is now slightly out of balance).

It's the law of physics, not my opinion regarding aqua-planing resistance. Same make of tyre, same tread depth on same car that weighs 1000kgs
Increase section width using same make of tyre with same tread depth and contact patch pressure is now lighter by some percent which means it now cannot cut through the same depth of standing water as effectively....
 
Last edited by a moderator:
Sorry Wayne, I appear to have started a small fight on your website. I only asked a question o.0

In other news, the guy at bush wants to see my car for a proper assessment but I can't do that till next week , he doesn't understand why I want to lower it at some point though :confused:
 
Thread edited "Heavily" on Waynnes behalf following a PM complaint recieved.

Guys can we stick to the policy of "if you don't have anything nice or constructive to say then don't say it."

I think this thead has had a few badly worded posts and a few backs have been got up. I'm sure this was not meant to happen by any of the parties involve. Bluntness has somehow slipped into rudeness and perceived personal attack.

This is not what we are about. We do not flame or argue on here. To those involved and you know who you are - take this as a very mild reprimant. Anyone causing arguements or rows or being blunt after this will, subject to moderators agreement have punitive acton applied. (This has never had to happen yet and hopefuly can be avoided but the friendliness of the forums must be maintainted at all costs.)
 

Similar threads


Please watch this on my YouTube channel & Subscribe.


Back
Top