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225x40x17

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Tampa
#1
I'm new to this forum but I've owned my fiesta for the last 3 years, with that said I'll get right on it, I've been contemplating into upgrading the width of my tires as I think 205 are kind of to thin, I do Auto crossing from time to time but I've kept the ride stock ride as it's a dd, so I wanted to know if anyone runs 225 40 17 and can provide with some experiences, is it worth the money... I can say I'm not running stock wheels mine are 17x7.5 with a 42 mm offset. Thank you in advance for your time.
 


shouldbeasy

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#2
You can fit them with rolled fenders - may rub on the top of the compression stroke.

Can't vouch for how they perform in Auto-X but having more tire for additional traction is never a bad thing - especially if you're tuned and pushing some serious torque to the front wheels.
 


OP
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Thread Starter #3
You can fit them with rolled fenders - may rub on the top of the compression stroke.

Can't vouch for how they perform in Auto-X but having more tire for additional traction is never a bad thing - especially if you're tuned and pushing some serious torque to the front wheels.
Thank you for the reply... I'm just a little nervous with the rub... could be unbearable for dd, I can deal with a little tug just not like some Honda Civic guys, that can't even turn the wheel...

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Indianapolis
#4
The best advice I could give you, if you're truly looking for performance, get the stickiest, DOT legal tire you can in 205. It will outperform any summer tire you get that's a 225, with your set-up.
 


OP
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Thread Starter #5
The best advice I could give you, if you're truly looking for performance, get the stickiest, DOT legal tire you can in 205. It will outperform any summer tire you get that's a 225, with your set-up.
Hello thank you for replying, I was advice the same at one point from a friend and ended up buying p zero Nero tires, but the minute you take a few turns the contact is not as sharp and they seem to not last long... I was thinking more sidewall for turns... If anything I'll go with 215 40 17 and go the LSD route and give it another shot.

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BRGT350

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#6
The best advice I could give you, if you're truly looking for performance, get the stickiest, DOT legal tire you can in 205. It will outperform any summer tire you get that's a 225, with your set-up.
Yep, I completely agree with this. Unless you are competing every weekend and fighting for a top podium spot, I would just go with the best tire you can buy in either P205/40, P205/45, or P215/40. The roads in Tampa are really nice, so you don't need the extra sidewall that is needed in other parts of the country. There are also 205 tires that run wide, so look over the actual measurements of the tire. From personal experience, I ran faster lap times on the stock tires than I did with a wider Yokohama tire. The reason was the compound and not the width. My fastest lap time on a road course was in my old Focus running 205 wide BFG race tires and not in my 300+hp Mustang running P275 wide street tires. Once again, it was the compound and not the width.

For turn-in, you want the least amount of sidewall. When you turn the steering wheel, there is a delay in the time the wheel turns and the tire contact patch turns. The higher the sidewall, the more delay there is. This delay affects what is felt in turn-in. Also, more sidewall changes how the tire heats up. More sidewall means more flex and more flex means more heat as the sidewall flexes.

Instead of a LSD, I would put that money towards the best dampers and springs you can buy along with a driver's school. Nothing improved my lap times faster than a trip to Team O'Neil. Nothing made me slower than throwing different parts on the car in between events.
 


M-Sport fan

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#7
There are NO 'street' summer tires available in that exact size (225/40-17) anyway (they'd be on my 17x8 Pro Race 1.2 summer wheels IF they existed!!), ONLY 00 to 50 tread wear rated, UN-streetable, THIN carcass construction, full-on DOT road race (or upper classification autocross) SLICKS. (Hoosier A7s/R7s) [:(]
 


Last edited:

neeqness

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#8
Since you are DDing too, a little extra sidewall may be beneficial. With a higher sidewall tire, you can add a little psi to reduce flex and loss of turn-in. It's a balancing act though because too much air pressure will make the car fill stiffer. Just play with it till you find what works best for you...if you decide to go this route.

A higher compound tire may give the best performance meanwhile sacrificing longevity. This may be a balancing act too with a DD. Depends what fits your budget, comfort, and performance needs. Are you looking for a max performance tire or willing to settle for an ultra? Lots of things to consider here...it all depends what your preferences are.
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OP
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Thread Starter #9
Since you are DDing too, a little extra sidewall may be beneficial. With a higher sidewall tire, you can add a little psi to reduce flex and loss of turn-in. It's a balancing act though because too much air pressure will make the car fill stiffer. Just play with it till you find what works best for you...if you decide to go this route.

A higher compound tire may give the best performance meanwhile sacrificing longevity. This may be a balancing act too with a DD. Depends what fits your budget, comfort, and performance needs. Are you looking for a max performance tire or willing to settle for an ultra? Lots of things to consider here...it all depends what your preferences are.
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That's why I was considering the 225s, I haven't experienced 215 so for now I'm going that route and see how much of a difference it makes... Thank you for the feedback!

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OP
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Tampa
Thread Starter #10
There are NO 'street' summer tires available in that exact size (225/40-17) anyway (they'd be on my 17x8 Pro Race 1.2 summer wheels IF they existed!!), ONLY 00 to 50 tread wear rated, thin, UN-streetable carcass construction, full-on DOT road race (or upper classification autocross) SLICKS. (Hoosier A7s/R7s) [:(]
You know I really didn't think of that, I didn't really do much research for the 225, so I decided I'm going 215s for now and see what gives.

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OP
F
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Tampa
Thread Starter #11
Yep, I completely agree with this. Unless you are competing every weekend and fighting for a top podium spot, I would just go with the best tire you can buy in either P205/40, P205/45, or P215/40. The roads in Tampa are really nice, so you don't need the extra sidewall that is needed in other parts of the country. There are also 205 tires that run wide, so look over the actual measurements of the tire. From personal experience, I ran faster lap times on the stock tires than I did with a wider Yokohama tire. The reason was the compound and not the width. My fastest lap time on a road course was in my old Focus running 205 wide BFG race tires and not in my 300+hp Mustang running P275 wide street tires. Once again, it was the compound and not the width.

For turn-in, you want the least amount of sidewall. When you turn the steering wheel, there is a delay in the time the wheel turns and the tire contact patch turns. The higher the sidewall, the more delay there is. This delay affects what is felt in turn-in. Also, more sidewall changes how the tire heats up. More sidewall means more flex and more flex means more heat as the sidewall flexes.

Instead of a LSD, I would put that money towards the best dampers and springs you can buy along with a driver's school. Nothing improved my lap times faster than a trip to Team O'Neil. Nothing made me slower than throwing different parts on the car in between events.
All great points, this is why I wanted feedback and your right I'm not going for the best time... I just want to go trash it a little and have a good time, now for the dampers I had a Dodge SRT 4 that I changed the suspension and that thing behaved like a horse, I haven't really thought of changing anything from the suspension for the St, don't want to mess it up... Which is why I've been thinking of just buying an LSD with better tires and call it a day...

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BRGT350

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#12
I run factory dampers with Mountune lowering springs and I am very happy with the results. My car sees one autocross a year and spends 99% of the time driving down poorly maintained Michigan roads, so having some compliance was important. I would suggest pairing the Mountune springs with Bilstein dampers for even better performance. You can maximize your tire's capability by pairing them with a proper suspension setup. One of the fastest cars in our local autocross club is my old 2011 Fiesta. It runs the Ford Racing suspension kit and ultra sticky tires. I may have double the power with my ST, but I still can't match my old Fiesta. A good driver, sticky tires, and some minor suspension tuning makes that car a giant killer. Last year it was 11th fastest out of 110 cars, and a lot of those were some high powered cars. It blew the doors of a new Focus RS.
 


Adub

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Seattle
#13
I run factory dampers with Mountune lowering springs and I am very happy with the results. My car sees one autocross a year and spends 99% of the time driving down poorly maintained Michigan roads, so having some compliance was important. I would suggest pairing the Mountune springs with Bilstein dampers for even better performance. You can maximize your tire's capability by pairing them with a proper suspension setup. One of the fastest cars in our local autocross club is my old 2011 Fiesta. It runs the Ford Racing suspension kit and ultra sticky tires. I may have double the power with my ST, but I still can't match my old Fiesta. A good driver, sticky tires, and some minor suspension tuning makes that car a giant killer. Last year it was 11th fastest out of 110 cars, and a lot of those were some high powered cars. It blew the doors of a new Focus RS.
What made you go with those over the Swift Spec-R Springs?
 


BRGT350

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#14
What made you go with those over the Swift Spec-R Springs?
the vast majority of parts I have on my ST are from Mountune, the springs were designed to work with the factory dampers, and I don't think the Swift springs were out at the time. I had developed a matrix to compare ride heights and spring rates and I don't think the Swift springs were on the matrix. It was Cobb, Eibach, Mountune, and H&R. The Mountune springs has a 5% increase in spring rate and a fairly conservative reduction in ride height. The more ride height reduction the more the suspension geometry needs to be altered in ways that can't be accomplished with the factory parts. I also wanted to work with the factory dampers so I wouldn't have to spend years trying to match spring rates and damping curves. Been there on way too many cars in the past. By using the factory dampers, I also knew that getting replacement dampers would be easy. For a car that sees one autocross a year, needs to work in all weather conditions, and is mostly for going to work, the Mountune springs were ideal.
 




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