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2001 Toyota AS300
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Discussion Starter #1
Hey all!

So I live in a a place where potholes are not far off dams and roads are about as good as a mining site.


So had this wacky idea to chuck on some all Terrain wheels on my Altezza Gita. Basically would get 15 or 16 inch mags and put one some meaty tires.


Please let me know if this would likely cause damage to the wheel bearings, shocks, bushings, etc.


Below is a photo of the type of wheel I'd wanna bolt on. It is a Continental 205/70/15


Cheers

MaGita



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2001 Toyota AS300
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Discussion Starter #3
15" wheels won't clear the front brakes, but 16" might

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Thanks for that! Reckon these tyres would fit within the arches though?

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2001 Toyota AS300
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Discussion Starter #5
if overall diameter is under 25"

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Cheers! So technically if I install a 3" strut spacers kit I could fit wheels with an overall diameter of 28" ?

Is this even possible or would that damage the drivetrain?
 

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2001 Toyota AS300
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Discussion Starter #7
Move to a better area or get a truck.
Ideally! Thought as much though. Will probably settle for an extra 1" of sidewall and get some all season tires put on a set of 16" wheels.

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Try putting that tyre or and old one from a trye dealer on the spare, fit it, then jack the suspension up as far as you can on only that wheel and see how much clearance there is. On the front go from lock to lock. Maybe try a 2WD Hilux wheel for size as it may have a tyre something like that on it already, but the offset is likely to be different which means the fronts are more likely to touch the bodywork on full lock. 16's were an option on these cars and Lexus rims should be easy to get as they are not the fashion item for most of us, 16 inch Camry's might fit too if your looking for some rims and want to keep the originals with the original tyres on them. Jacking up the suspension puts more load on the CV joints wearing them faster and the bigger the angle the more power you loose through the CV joint. Your speedo will be out, maybe not many cops out there anyway and you will loose a bit of power with the extra diameter. There are a lot of online tyre calculators for working out the percentage difference with different sized tyres. Am interested to see what happens.
 

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2001 Toyota AS300
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Discussion Starter #13
Try putting that tyre or and old one from a trye dealer on the spare, fit it, then jack the suspension up as far as you can on only that wheel and see how much clearance there is. On the front go from lock to lock. Maybe try a 2WD Hilux wheel for size as it may have a tyre something like that on it already, but the offset is likely to be different which means the fronts are more likely to touch the bodywork on full lock. 16's were an option on these cars and Lexus rims should be easy to get as they are not the fashion item for most of us, 16 inch Camry's might fit too if your looking for some rims and want to keep the originals with the original tyres on them. Jacking up the suspension puts more load on the CV joints wearing them faster and the bigger the angle the more power you loose through the CV joint. Your speedo will be out, maybe not many cops out there anyway and you will loose a bit of power with the extra diameter. There are a lot of online tyre calculators for working out the percentage difference with different sized tyres. Am interested to see what happens.
Finally, thanks so much for this useful information! I'm definitely planning on keeping my original wheels for the long distance trips. I'm currently on the hunt for some suitable used 16" rims.

With regard to jacking up the suspension as much as it can go what do you mean by that exactly? Can this stock suspension be adjusted slightly?

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This is new ground, love it. Put a trolley jack, as it can move around a bit, under the lower suspension arm as close to the wheel as you can and jack until another wheel starts to come off the ground. Or use a wheel ramp to do the same job, be safety conscious when doing it, use axle stands and don't get under the car. One of the cars I've had only needed 80mm of lift on any wheel before another wheel came off the ground. You need the opposite, keep the stock sway bars, maybe even unbolt an end link on the sway bar when doing the jacking up test to make it easier to lift the wheel to find out how much clearance there is. Might not get the suspension completely compressed but it will give you an idea of how much clearance is left and what is going to touch first with bigger tyres in there. There is not a huge amount of room in these cars like there is in a 4x4.
For lift you could make a 10 or 15mm spacer to go in between the top of shock and the bodywork with the stock bolts. As the shock is only part of the way along the suspension arm, the wheel end should gain at a guess 15 to 25mm lift in the car. Just thinking of things you could do that are easily reversible and not change the car too much or the handling might get weird. These are a luxury sports car after all.
I'm not sure what other springs and shocks could be used to jack it up, some of the JZX, JZS, Crown or Chaser cars (jap Toyota imports) have very similar suspensions which may have longer shocks, but not sure on that one. Just remember that IS300 shocks were swapped into one to lower it more, can't remember the details as it wasn't mine.
Most of the times I've tried to put bigger wheels on something they seemed to rub on the footwell behind the accelerator pedal on full lock. Which is sometimes due to decreased offset rims, which means having rims which sit further out, this also messes with the steering and braking and try to avoid doing it if possible. You don't want a tyre hitting anything solid on the car, as they might try to stop turning at the worst possible moment when going over a hump, hole or on full lock.
Bigger diameter and higher sidewalls is much better than width for rough roads, which you have already picked. Don't get too carried away as it might be less work, cheaper and quicker to just buy a SUV, it might do a better job as well, maybe a similar year RX if you like Lexus's.
 
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