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Will 225/45/15 work on Sparco Terra 15x7

brapppp33

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#1
Anyone have experience running this combo or similar? I'm going on my first tire / wheel upgrade and like the thought of this but not sure it will work with out more modification. I'm wondering if this can be installed on a stock set up without fender adjustments or need for a lot of extra work. Any input would be very helpful, thank you!
 


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#2
Do you know the offset for the Terra's that you're looking at?

I believe the tire would work just fine, without more modification, unless your offset changes too much. A 225/45R15 is about 0.8" wider then oem but it is also 2.1% smaller in diameter making it a give and take on size and fitment. I recently put 205/55R15s onto a 15x6. My tire is a bit taller then your new setup but it fits well and doesn't rub.
 


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brapppp33

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Thread Starter #3
Do you know the offset for the Terra's that you're looking at?

I believe the tire would work just fine, without more modification, unless your offset changes too much. A 225/45R15 is about 0.8" wider then oem but it is also 2.1% smaller in diameter making it a give and take on size and fitment. I recently put 205/55R15s onto a 15x6. My tire is a bit taller then your new setup but it fits well and doesn't rub.
Yessir, 40mm offset on the rims I'm looking at. That's good to hear though, I'm just very uncertain with this stuff as I'm getting my feet wet. I've read that 225.45.15r work really well on 15x8 dekagrams but I haven't seen anything about 15x7 rims
 


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#4
Nice, I almost did the same setup! Below are a few resources that are pretty helpful. The last link is one with your specs. As the rim would give you 8mm more poke (out), and the tire size increases by 20mm, to me that means the new set up would be about 18mm closer to the fender then your current setup. I've seen a few people throw 25mm spacers trying to get their rims flush to fender or to get poke. I'd be comfortable with those sizes.

Tire Size Comparison: https://tiresize.com/comparison/
Tire Size Calculator: https://tiresize.com/calculator/
Rim Offset: https://www.willtheyfit.com/

https://www.willtheyfit.com/index.p...ct2=45&wheel_size=15&wheel_width=7&offset2=40
 


Last edited:
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#5
I've read that 225.45.15r work really well on 15x8 dekagrams but I haven't seen anything about 15x7 rims
Or were you more concerned with the tire to rim fitment? A 225 should fit on a 7" without issue. Your tire will be a bit wider then the rim giving it more of a 'meaty' look then the stretched look. Some say it is advisable not to extend the tire beyond the rim width if you are really pushing the limits. I've generally gone the meaty route but I am not participating in any time attacks.
 


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brapppp33

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Thread Starter #6
Nice, I almost did the same setup! Below are a few resources that are pretty helpful. The last link is one with your specs. As the rim would give you 8mm more poke (out), and the tire size increases by 20mm, to me that means the new set up would be about 18mm closer to the fender then your current setup. I've seen a few people throw 25mm spacers trying to get their rims flush to fender or to get poke. I'd be comfortable with those sizes.

Tire Size Comparison: https://tiresize.com/comparison/
Tire Size Calculator: https://tiresize.com/calculator/
Rim Offset: https://www.willtheyfit.com/

https://www.willtheyfit.com/index.p...ct2=45&wheel_size=15&wheel_width=7&offset2=40
Hey thank you for plugging that in and providing those resources. I'm going for a look that is more flush to the fender, so I am glad to hear that would be the case. I am basically going for a similar look to this: https://www.fiestastforum.com/threads/15x8-and-225-45r15.10079/

Or were you more concerned with the tire to rim fitment? A 225 should fit on a 7" without issue. Your tire will be a bit wider then the rim giving it more of a 'meaty' look then the stretched look. Some say it is advisable not to extend the tire beyond the rim width if you are really pushing the limits. I've generally gone the meaty route but I am not participating in any time attacks.
A little bit, yes. I just have not seen anyone online running this set up, read a lot about 225s having rubbing issues so I want to dot the I's and cross the T's before buying. I do like the meaty look quite a bit and that's the goal, meatier and more flush with the fenders than stock. I'm not really looking to track my car for awhile so purely cosmetics at this point
 


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#7
I just have not seen anyone online running this set up, read a lot about 225s having rubbing issues so I want to dot the I's and cross the T's before buying
That setup does look good. I think the rubbing would really depend on rim offset. Hopefully someone else with 225 experience can chime in. Have a good one and best of luck!
 


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brapppp33

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Thread Starter #8
That setup does look good. I think the rubbing would really depend on rim offset. Hopefully someone else with 225 experience can chime in. Have a good one and best of luck!
Appreciate the help man! I’m going to do a little more research but feeling more comfortable now. Can’t wait to get this ready for summer
 


Dpro

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#9
Put a 225 on a 8 at least 7’s are rather narrow for a 225. It will result in a lot more sidewall flex if you put them on a 7 which will possibly deaden your turn in and make it feel less nimble.
 


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#10
Appreciate the help man! I’m going to do a little more research but feeling more comfortable now. Can’t wait to get this ready for summer
Hey, one other thing came to mind. If you check the tire manufacturer for the tire and tire size you want they will put the recommended min and max rim width. Should settle any uneasiness if it's within their limit.
 


kevinatfms

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#11
Stick to 205/50R15 for a 7" wide wheel. Too wide a tire on too small a wheel will result in killing the turn in response. That is ten fold on a car that is known for how good the turn in is in stock form.

I run a 205/50R15 RS-RR on a 15x7 Terra and they are about perfect. Plenty of grip but still have great turn in response.
 




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