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Discussion Starter #1
Hello,

I’m considering looking for a mild suspension drop (if available) and a lighter and shorter tire/wheel package. Dropping from a 28” OD to somewhere around 25”.

The thought is an indirect gear reduction, better aerodynamics, less unsprung weight, etc. Basically just sporting it up a bit.

Besides messing with the speedometer (assuming they can’t reflash the Tire/wheel package) do you know of this would raise Hell with the hybrid powertrain? Again, same diameter tires front to rear...just less weight and easier to move the vehicle around.

Thanks!
 

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Also, more loss of traction when needed. Also, if lower profile, prone to blow-out if ya hit a rock or curb, or the like. Not saying you can't but I'd make a serious PROs vs. CONs list and ask a tire expert at a reputable tire shop for REAL WORLD advice, and send a letter to Toyota asking why they choose the tire size they did. Also, does the void warrantee, if you mess with the pull / strain on the CVT, etc. ???

Good luck!
Peace!
 

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..."if you mess with the pull / strain on the CVT, etc. ???"

Good luck!
Peace!
I agree about doing a pro vs, con list,but this isn't a concern,since there IS no conventional CVT here,and there would be no difference in the amount of torque passing through the trans in any case,since the added torque multiplication takes place AFTER the trans.
 

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Discussion Starter #4
Thanks all :).

Yea there are cons to consider. Ground clearance and looking silly being the big one. Plus any electronic gremlins that surface as the hybrid system is more specialized than say a simple internal combustion engine and viscous center diff (ie old school Suby).

At freeway speeds it would be revving higher. Also not sure if the max electric speed would be reduced (mph vs load based?). At low speeds it should feel like a lighter vehicle and overall more responsive. Basically the opposite to putting heavy oversized wheels/tires on it.

I’ll get some firm details before I go Frankensteining. Cheers!
 

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Why not get an a Honda Civic? You'll get much better advice on Civic forums and will fit in much better with the crowd. :D
 

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Aside from rendering the car worthless on the used car market, just a bad idea all around. If you want something "sporty", don't drive a hybrid.
 

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Hello,

I’m considering looking for a mild suspension drop (if available) and a lighter and shorter tire/wheel package. Dropping from a 28” OD to somewhere around 25”.

The thought is an indirect gear reduction, better aerodynamics, less unsprung weight, etc. Basically just sporting it up a bit.

Besides messing with the speedometer (assuming they can’t reflash the Tire/wheel package) do you know of this would raise Hell with the hybrid powertrain? Again, same diameter tires front to rear...just less weight and easier to move the vehicle around.

Thanks!
This is a joke right? This seems like the silliest idea. To install a smaller 25" diameter tire/wheel package would look so goofy and affect performance in such a negative way I'm shocked that you would even consider the idea.
 

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Discussion Starter #8
Reducing weight, drag, and improving torque and aerodynamics are some of the principals of eco-modding. Right?

If I suggested heavier wheels, taller tires, and a lift kit would that be more or less stupid for an economy car?

Not trying to piss in your Cheerios. Just didn’t know theory-crafting was frowned upon.
 

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There are two different tire sizes for R4H 235/55/R18 and 225/65/R17. The first one is for sporting type driving and the second one for more comfortable driving. I have both. Summer tires are R18 and winter tires are R17. I like more R17, because my driving profile is more comfortable than sporty.
 

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I’m considering looking for a mild suspension drop (if available) and a lighter and shorter tire/wheel package. Dropping from a 28” OD to somewhere around 25”.

The thought is an indirect gear reduction, better aerodynamics, less unsprung weight, etc. Basically just sporting it up a bit.
Not sure if you can actually "re-flash" the ECU to recognize the new wheel / tire size given how technical and complicated the Synergy Drive ECUs are... But, I don't see any technical reason why you couldn't do it assuming you match sizes at all 4 corners. There's also no reason it wouldn't provide for better acceleration - in fact, it should based on having less rotational mass and an effectively a shorter "final drive". However your trade off is going to be increased gas mileage - likely to the extent that you're going to be unhappy seeing as you probably bought your hybrid for better mileage to begin with (I'm guessing).

If you reduce your overall diameter from 28" to 25" you're effectively reducing your circumference by 20%. This means that instead of being able to get into an EV glide mode up to about 47mph, you'd be forcing your ICE to start at about 37.5 mph. This would have a adverse effect on your ability to run with the ICE off - unless you spend all your time at less than 30mph or something. Since ICE off gliding is where a lot of the fuel savings are to be had, any advantage the smaller wheel / tire combo might provide (in terms of being slightly lower to the ground, less rotational weight, etc) would be very likely offset in a significantly negative way.

Not that this should really matter on public roads, but your top speed will also be reduced by about 20%. This has nothing to do with the power of the vehicle or it's size / aerodynamics. Rather it has to do with the maximum speed that MG1 and MG2 can spin before turning themselves into very large electromagnetic grenades. The computer limits their RPMs and will cut power if you hit their limits.

Everyone's got their own personal preference in aesthetics, and if you're looking for a different look and feel then I say by all means give it a go... But you probably will want to look at the trade-offs pretty closely depending on your driving style. If you like to floor it off every stop light, take the qualifying line on every turn you make, and don't care so much about fuel economy then it might be fine! Although in that case it might be worth finding a different vehicle in general that more closely fits your driving style... like a Subaru.

In the end it's your car... enjoy it however you see fit!!! :smile
 
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Discussion Starter #11
Not sure if you can actually "re-flash" the ECU to recognize the new wheel / tire size given how technical and complicated the Synergy Drive ECUs are... But, I don't see any technical reason why you couldn't do it assuming you match sizes at all 4 corners. There's also no reason it wouldn't provide for better acceleration - in fact, it should based on having less rotational mass and an effectively a shorter "final drive". However your trade off is going to be increased gas mileage - likely to the extent that you're going to be unhappy seeing as you probably bought your hybrid for better mileage to begin with (I'm guessing).

If you reduce your overall diameter from 28" to 25" you're effectively reducing your circumference by 20%. This means that instead of being able to get into an EV glide mode up to about 47mph, you'd be forcing your ICE to start at about 37.5 mph. This would have a adverse effect on your ability to run with the ICE off - unless you spend all your time at less than 30mph or something. Since ICE off gliding is where a lot of the fuel savings are to be had, any advantage the smaller wheel / tire combo might provide (in terms of being slightly lower to the ground, less rotational weight, etc) would be very likely offset in a significantly negative way.

Not that this should really matter on public roads, but your top speed will also be reduced by about 20%. This has nothing to do with the power of the vehicle or it's size / aerodynamics. Rather it has to do with the maximum speed that MG1 and MG2 can spin before turning themselves into very large electromagnetic grenades. The computer limits their RPMs and will cut power if you hit their limits.

Everyone's got their own personal preference in aesthetics, and if you're looking for a different look and feel then I say by all means give it a go... But you probably will want to look at the trade-offs pretty closely depending on your driving style. If you like to floor it off every stop light, take the qualifying line on every turn you make, and don't care so much about fuel economy then it might be fine! Although in that case it might be worth finding a different vehicle in general that more closely fits your driving style... like a Subaru.

In the end it's your car... enjoy it however you see fit!!! :smile
Thanks! The tech insight and friendly welcome is appreciated :).

I’m definitely just asking the “what if’s” and have no desire to bastardize a good vehicle. No stanced camber, 15” wire wheels, or even trying to make a sleeper. A change in shoes is often quite noticeable and totally reversible. Mainly trying to make it a bit more Subaru than SUV while retaining the Toyota build quality.
 
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