downgrading to 17"s?

Ms3Hova

Member
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Mazda Speed 3
so i'm new to the whole modding scene. i was thinking about getting some konig feathers for my car because they are light, cheap, and look nice ( i like the multispoke look on the MS3). anywho, i was just wondering what problems it would cause to downgrade a wheelsize from the stock to 17".



any feedback is much appreciated.

be nice i'm a noob. (dunno)
 
It's not down grading. You're just getting a smaller wheel. Many would argue that 17s are THE performance wheel. I'd agree.

Just make sure your offset is ok. Something as close to 52.5mm as you can get. You won't have any front caliper clearance issues.
 
going from 18 to 17 will not cause any problems. Some people were running as low as 15's for snow tires. Going that small will probly cause you a loss in handling, but 17's might actually be beneficial if you choose to autocross the car ... like swamp said, just be careful of the offset so that you dont have any problems clearing the brake calipers
 
for 7.5" wheels 45-50 offset fill out the wheel well nicely. Double check the hub bore with whoever you get the wheels from, its not listed on alot of sites. 67.1 is what you need.

(ive got a reg 3 not speed) so you should be able to get a lower offset since you have wider fenders.
 
15s won't clear the front calipers on a Speed 3. 16s likely wouldn't, either.



going from 18 to 17 will not cause any problems. Some people were running as low as 15's for snow tires. Going that small will probly cause you a loss in handling, but 17's might actually be beneficial if you choose to autocross the car ... like swamp said, just be careful of the offset so that you dont have any problems clearing the brake calipers
 
my apologies, the 15s do not fit. I did a search though and 16's will most defintely will fit:

http://www.mazdas247.com/forum/showpost.php?p=2785763&postcount=23


I can't see any details in that photo, but that wheel looks like it's steel.

Steel wheels have thinner walls than aluminum wheels because steel is much stronger than aluminum. The steel wheel will therefore likely have a larger I.D. (thereby providing greater caliper clearance than an aluminum wheel).

The front rotors on a speed 3 are 12.6". The stock single piston sliding calipers takes up more space than multi-piston fixed calipers would. There could very likely be interference issues with the front caliper when attempting to install a 16" aluminum wheel on an MS3. Plus, what would be the point? A very tall sidewall would be needed in order to maintain the stock rolling diameter, so overall vehicle handling would greatly suffer.

I wouldn't recommend using a 16" aluminum wheel to anyone with a Speed 3.

My '99 1LE Camaro Z28 used 11.8" front discs with dual piston sliding calipers and the stock 16" aluminum wheels were a tight fit. There was perhaps 1/4" clearance between the front caliper and the wheel I.D. There's no way those wheels would have fit if the rotors were 0.8" larger (12.6" total) in diameter.
 
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Those calculators only give good approximations of tire sizes.

Actual sizes (e.g. tread width and diameter) can vary slightly.

The Tire Rack publishes ACTUAL manufacturer specs for tire diameter, tread width, etc. for virtually every tire it sells. Compare various tires that are "the same size" and you will see that they are not.

Example: 225/45/18 Tire Diameters:

www.tirerack.com

Pirelli P Zero Rossa- 25.7"

Michelin Pilot Sport - 25.8"

Continental Contisport 2 - 25.9"
 
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Wow, stock protege5 wheels barely cleared the brakes on my mz3, I would assume though that every wheel is slightly different, and some 16s may not fit.

What diameter were the stock Protege wheels? (I'm new to the Mazda world). Did you install them on a Speed 3?

Other vehicles I've had experience with suggest that a 12" rotor is a good "rule of thumb" limit for a cast aluminum 16" wheel. Some 16s may clear the speed 3s calipers, but some undoubtedly will not.

I just measured the distance between the front driver side caliper and the stock 18" wheel on my Speed 3. It's about 1-1/4". A 16" wheel would reduce that clearance to 1/4", assuming everything else (e.g. wheel rim thickness, offset, etc.) were identical. That's cutting it pretty close.
 
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ive got a regular 3, and there is roughly 1\4" gap from brakes to wheel. (I run the p5 wheels, 16" for mountain trips where all season tires may be needed)

I can throw them on and get some measurements if you want.
 
ive got a regular 3, and there is roughly 1\4" gap from brakes to wheel. (I run the p5 wheels, 16" for mountain trips where all season tires may be needed)

I can throw them on and get some measurements if you want.

Which 3 do you have? The "S" models use 11.8" front rotors, while the "i" models use 10.9" front rotors.

You must have an "S" if you've only got 0.25" of clearance between the caliper and the 16" wheel.

The Speed 3 uses 12.6" front rotors, which are 0.8" larger than the 11.8" rotors. That's a difference of +0.40" (half the difference in diameter) in terms of determining caliper clearance, which suggests that your 16" wheel would not clear the Speed 3's calipers.

Personal experience with several vehicles I've owned suggest the same thing. That's why I don't agree with some claims that 16" aluminum wheels work on a Speed 3. Plus, I would want at least 1/4" of clearance between the rotor and the wheel in order to prevent caliper damage in the event of a bent wheel (e.g. from a pothole in the road). I maintain that a 17" wheel is the minimum safe diameter to install on a Speed 3.
 
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i would agree unless of course you went with a steel wheel for winter driving as the price diff in 16" vs 17" snow tires is huge.
 
i would agree unless of course you went with a steel wheel for winter driving as the price diff in 16" vs 17" snow tires is huge.

No 15" wheel is going to clear a Speed 3's front calipers. Many (all") 16" aluminum wheels won't clear a Speed 3's front caliper.

I'm not even certain that every 16" steel wheel would fit. A spacesaver probably will (haven't yet checked the size of my Speed 3's spacesaver), but those aren't designed for long term use.

Using a 16" (steel only - assuming it would fit) wheel on a Speed 3 for winter use would mandate the use of a lame snow tire (e.g. 205/60/16). That's going to seriously compromise the handling characteristics of the car. The heavy steel wheel would further contribute to that problem.

Anyone who has the coin to afford a new Speed 3 should be able to cover the cost difference between a low buck 15" winter set-up and a decent 17" aluminum winter set-up.
 
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16X8" FD RX-7 wheels will fit the Speed3. You just have to bore out the centerbore to fit the hub. I put my set on a Speed3 for a few autoX runs. It felt really nice on the 245/45-16 Hankooks.
 
16X8" FD RX-7 wheels will fit the Speed3. You just have to bore out the centerbore to fit the hub. I put my set on a Speed3 for a few autoX runs. It felt really nice on the 245/45-16 Hankooks.

Many people wouldn't want to go through the hassle of having the hubs bored, but that's good information.

I didn't think 245s would fit on a Speed 3; I guess I was wrong.

How has your Speed 3 done in Autocrossing?
 
Many people wouldn't want to go through the hassle of having the hubs bored, but that's good information.

I didn't think 245s would fit on a Speed 3; I guess I was wrong.

How has your Speed 3 done in Autocrossing?

The guy that owns it has been out to a few events, but he has been running on the stock rubber. The car felt good when I drove it, but the stock rims are way to skinny to be ideal for AutoX.
 
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