kezwaldo

i have just swapped my sti 17x7.5 wheels running on 235/45/17s to 17x7 invoit wheels running on 215/?/? and the car now looks undertyred and the gap between arch and wheel looks a bit silly.............what are the biggest tyres i can fit now on my new wheels need to close the gap a bit will i notice difference by putting 225s on as i dont think 235s will fit now!!!!!!!! heres a pic any way..........

lofty35

lowering it on springs, I will have some tein springs on struts in a couple of weeks if u want at a good price. cheaper than buying tyres and will look loads better

kezwaldo

are they just the springs ??????? i have sti suspension at the moment and would only want to change springs ,although isnt the 45 on atytre the wall size if so i had 45s on before so really should be no difference

lofty35

there tein springs, they will still be on the strut but I can take them off.
ye 45 is tyre wall size, these springs will lower it by 35 mm
£65

Fudgey

iTrader: (1)

If you have stayed with 17 inch rims then the tyre profile should be the same to keep the same rolling radius.
If you go bigger or smaller your speedo will over on under read, and it could screw the diffs if its massivly different.

Do you have a pic of the car on the old rims?

Also, what front brake setup are you running? The standard cast 4 pots, and bigger discs? Your discs look much bigger than mine lol

kezwaldo

i have 335mm god speed discs on front mate 4 pots braided hoses .....

blackvenom

The "45" on the tyre is the wall depth but its based on the tyre width, so a wider wheel will have a thicker side wall.

LuckyWelshchap

As per my reply on your other thread, since you've gone from 235 to 215 and are running 45's then the reduction in tyre height is 18 mm ie. your tyres have 'shrunk' about 1.8cm in the arches.

Looking at the pics that 3/4in makes a lot of difference.

For them to 'grow' back to the same proportion you'd have to have 215/50/17's.

I'm not sure how much percentage width of tyre you can get on a wheel (since you had 235's on a 7.5 I presume that 123% is possible, 7.5in being 190.5mm, so you had 235's on a 190.5 wide wheel) but on the same basis 220 or 225 is probably the maximum on a 7in rim.

A half-decent tyre dealer would be able to help you out.

EOEUMC

iTrader: (5)

I have just had this when changing from 225/45/17
I have also lowered the car, well just had STi suspension fitted and the gap seems to be no lower and in fact a little bigger.
I have been told that the tyres I have now fitted (215/40/17) could do with being a little bigger, but not wider! So may be you should be looking at 45's. Not sure if 50's would fit ok without scraping etc.

So basically as lucky has said above

JohnD

iTrader: (5)

The standard tyre size on your car was 225/45/17 By using 235/45/17 you raised the gearing. The effect would be to make the speedo under-read (as speedo's usually over-read slightly by design, it probably finished up accurate!) It would also reduce the acceleration very slightly. You're now using narrower tyres than standard and if still 45 profile, will lower the overall gearing! As you say, the wheelarch gap is now larger!
Why have you used the wrong tyre size on both occasions?
Lowering springs such as the Prodrive will improve the look and handling but if you get a second-hand set, make sure you get the modified bump stops with them (part of the original kit)

JohnD

kezwaldo

i bought the car with the 235s on mate and then swapped then as the was kerbed and paint flaking off the wheels iver swapped them for are 215a as you see in picture ........i have never gone and bought tyres since i owned car ,,,,,,,,,,just been to tyre garage and the say 215/50/17s will bring the them back to about right on my rims or the 225/45/17 tyres will slightly increase the gap left by old tyres what do you think?

LuckyWelshchap

The first thing I think is that I ought to go into the tyre business, if a professional has offered an option the same as me.
Er... one the other hand perhaps they were an apprentice or a crap tyreman

Anyway on a serious note I'd have said that increasing the profile to 50 has the big disadvantage of less tread on the road, less grip etc.

I'd also say that John D's info about 225/45/17 being the manufacturer's recommended size has an awful lot going for it, the car maker themselves say it.

And of course if the manufacturer's recommended sizes are used then that's how the car was meant to look.

Finally, being really pessimistic, if you had an accident that was (in part at least) put down to tyres you might have a problem when it comes to any insurance claim.

These points are food for thought, not advice as such.

kezwaldo

mate im going with the 225/45/17s for sure i didnt realise that 50s was a disadvantage im just going to get 4 decent tyres (225/45/17s) and drop it 35mm job done !!!!!! thanks for the advice.

LuckyWelshchap

No probs.

I hope the job's a good 'un for you.