LRR tires for Miata

[1337]

d0sitmatr, thanks for the help!

Originally Posted by d0sitmatr

if it was me, Id go at least a size larger, it will definitely help lower your RPM

Good point. I wish Mazda would use taller fifth gears. Taller tires will help a little, but I'll still be over 3000 RPM at highway speeds.

Originally Posted by d0sitmatr

road noise could be cut by 1/2 just by upsizing 1 size.

I believe you, but I haven't heard this before. Is it common knowledge that taller tires are quieter? If so, why is this the case?

[Ladogaboy]

From what I've seen, Discount Tires has access to a few tires that no one else can get. It works both ways, though, because I have gone to them for tires that they told me they couldn't get.

Also, I agree with d0sitmatr... I actually regret not getting slightly taller tires. I only lost 1% with my current setup, but still, I would have rather gained 1% (basically 9 less revs per mile). Especially with my car, where freeway cruising speeds just put me into boost with my turbo (hurting economy).

[d0sitmatr]

the closer/lower the aspect on the tire means more transference of road noise to the rims, which connects directly to the hub and so on and so forth + Mazda's are known for not using as much dampening in their vehicles, which isnt a problem for me personally, but some people dont like a lot of road noise.

my protege5 is in the same boat, our hwy speeds are 70mph and at that speed, my RPM's are at 3300-3400. far too high for my liking. I have little recourse but to go a couple exotic routes by using either a 626 LS (V6) transmission, which requires some machining work or look for a diesel trans from Europe that is a straight swap.
the Miata being RWD gives you an option that I dont have with my mp5 being FWD, which is you cna look at a different gearset in the rear pumpkin.
find out what your rear gear set is and go with 1 or 2 sizes smaller (EX: if you have a 4:44 rear, then look at a 3:11 rear) this itself will drop your RPM considerably. but you have to be careful not to go too tall as that in itself can affect mpg for the worse, by making the cars engine work that much harder to maintain speed.

[1337]

Originally Posted by d0sitmatr

the closer/lower the aspect on the tire means more transference of road noise to the rims, which connects directly to the hub and so on and so forth + Mazda's are known for not using as much dampening in their vehicles, which isnt a problem for me personally, but some people dont like a lot of road noise.

my protege5 is in the same boat, our hwy speeds are 70mph and at that speed, my RPM's are at 3300-3400. far too high for my liking. I have little recourse but to go a couple exotic routes by using either a 626 LS (V6) transmission, which requires some machining work or look for a diesel trans from Europe that is a straight swap.

I used to have a Protege (manual) too. I contemplated doing a 5th gear swap, but I never got around to doing the swap.

Originally Posted by d0sitmatr

the Miata being RWD gives you an option that I dont have with my mp5 being FWD, which is you cna look at a different gearset in the rear pumpkin.
find out what your rear gear set is and go with 1 or 2 sizes smaller (EX: if you have a 4:44 rear, then look at a 3:11 rear) this itself will drop your RPM considerably. but you have to be careful not to go too tall as that in itself can affect mpg for the worse, by making the cars engine work that much harder to maintain speed.

In Australia, the 2006+ Miatas have a 3.70 final drive ratio. In the US, 2006+ Miatas have a 4.10 final drive. This thread discusses swapping a 4.10 into an Australian car that came from the factory with a 3.70. In the case of my car, I might want to swap in an Australian 3.70 to replace my 4.10.

I'm torn about whether I want to put a taller final drive ratio in. It's an expensive job, and it will make the car more sluggish off the line. The ideal situation would be to add a taller 5th gear while keeping the current final drive ratio (this also would be a not-insignificant amount of work).

[d0sitmatr]

Originally Posted by 1337

In Australia, the 2006+ Miatas have a 3.70 final drive ratio. In the US, 2006+ Miatas have a 4.10 final drive. This thread discusses swapping a 4.10 into an Australian car that came from the factory with a 3.70. In the case of my car, I might want to swap in an Australian 3.70 to replace my 4.10.

I'm torn about whether I want to put a taller final drive ratio in. It's an expensive job, and it will make the car more sluggish off the line. The ideal situation would be to add a taller 5th gear while keeping the current final drive ratio (this also would be a not-insignificant amount of work).

that 3.7 from a 4.1 wont gain you a whole lot. whether the cost is worth the reward is up to the individual at that point. but I dont think it would be as expensive as you think to replace. the pumpkin itself should be a straight swap, so your cost would mostly come from buying/shipping it from AU. that WILL be pretty expensive, that is for certain !
there are other options, look into aftermarket gearsets for the Miata, Im sure there has to be some available, plus, Im betting someone, somewhere, has a taller 5th gear ?
the Miata has a HUGE fanbase, so Im guessing there should be tons of resources out there. unlike the protege which is sort of like the "basturd" child

[euromodder]

Originally Posted by 1337

I also noticed that the Michelin HydroEdge is available in 205/55R16.

If you're willing to go up to that size (about 3% taller) you could also get the Michelin Energy Saver .

Maybe in Canada as they're not available in the US (the A/S is a different tyre)

Do you drive the Miata in winter ?

[1337]

Originally Posted by d0sitmatr

that 3.7 from a 4.1 wont gain you a whole lot. whether the cost is worth the reward is up to the individual at that point. but I dont think it would be as expensive as you think to replace. the pumpkin itself should be a straight swap, so your cost would mostly come from buying/shipping it from AU. that WILL be pretty expensive, that is for certain

Yeah, I agree. I'm not sure how many of these are available either, I started a WTB thread to see if anyone is interested in selling one of these differentials.

Originally Posted by d0sitmatr

the Miata has a HUGE fanbase, so Im guessing there should be tons of resources out there.

True. My car has an 0.814 5th gear. I started a thread about 5th gear swaps in the Miata forum, and it seems that there are other cars that I could pull a taller 5th gear from. For example, the 87-91 RX-7 has a .691 5th gear. Perhaps Mazda still makes that part. However, if the part is discontinued, I would have to pull a used one from a 20+ year old, possibly abused, sports car transmission. I'm not sure if I'd feel comfortable putting a 20-year old used part into my newish car's transmission.

[PaleMelanesian]

When Round and Black Becomes Lean and Green

Be sure to check the other tabs with charts. You can balance the various performance aspects to see what works best for you.

[d0sitmatr]

Originally Posted by 1337

True. My car has an 0.814 5th gear. I started a thread about 5th gear swaps in the Miata forum, and it seems that there are other cars that I could pull a taller 5th gear from. For example, the 87-91 RX-7 has a .691 5th gear. Perhaps Mazda still makes that part. However, if the part is discontinued, I would have to pull a used one from a 20+ year old, possibly abused, sports car transmission. I'm not sure if I'd feel comfortable putting a 20-year old used part into my newish car's transmission.

that doesnt sound like a good idea to me either
it cant hurt to look around.
I considered tossing a different trans in my 99 ranger xlt before I got rid of it back in Jan, it had the 3.0L engine and honestly had some decent gear ratios, but it simply didnt have the HP/torque to drop the rev's any, and I would have ended up losing mileage.

[1337]

One more tire to throw into the mix: Sumitomo HTR A/S PO1

Consumer reports rates its noise as Excellent, and rolling resistance is Good. So far as I can tell, this is the only tire that received an Excellent rating for noise.

Does anyone have any experience with these tires?