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Is 17 inch plus wheels bad for a lil car? subs, auudio.... (1 Viewer)

loquasagacious

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actually no - a 17" wheel dictates a lower profile tyre which will be more prone to puncture...
 

petar13

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Hey,

on my civic, is it feasible to install 17 inch wheels on it, or is 16 inch the maximum? i hear that the larger wheels, the less lasting the tyres become...hmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm mm.

things to do to my car:

alloys, subs, car audio, exhaust

things id never do to my car

put in turbos, chargers, change odometers
Hmm. I don't know if you meant speedometer or tachometer... but if you install larger wheels, you may have to get your speedo recalibrated, especially if making a big jump from (lets say) 14" to 17". Thankyou for not saying neons.
 
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loquasagacious

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No a smaller target area probably renders sidewall punctures less likely...

More importantly though when a low profile tyre hits a pothole (or something sharp miscellaneous) it does not have a large 'air cushion' to absorb the impact.

Whereas a 65 profile tyre can flew alot to absorb an impact a 25 profile can not and thus the lower profile tyre will more readily puncture.

Another way of thinking about it is to imagine a 65 profile tyre - when it hits something the tyre is pressed between air and the object. When a 25 tyre hits something there is less air so it is more like being squished between the mag and the object.

Case in point one of my mates mum has an XR8 and as a result of the low profile tyres and shit house roads she lost 3 tyres in a year....
 

loquasagacious

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Tsk tsk petar - no need to recalibrate the speedo - IF you do the maths.

You just need to preserve the original complete wheel/tyre diameter eg as the rim gets bigger the tyre gets skinnier. It should take about five minutes to knock up a spreadsheet that gives you the sizes that are possible.
 

petar13

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Ouch.

True that, you would need some very low profile tires to make up for those on a 14". But if you take a look at some 'tricked out' civics, you will see that regardless of tire size, the wheels are simply much larger than stock rim + tire. There's no avoiding it there.

:D But yeah, generally speaking recalibration can be avoided if you can keep the size the same (sane).
 

loquasagacious

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It would adversly effect acceleration and top speed. It would improve handling by making it more precise and controllable.
 

Zozo6969

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Putting bigger wheels than the stock wheels can be bad in measuring how fast you are going. Because the bigger wheel has a bigger circumference, it doesn't revolve as much as a smaller wheel at the same speed. So, the dashboard says you are going 60 because the wheels does 10 revolutions a second or whatever, but because of the bigger circum, 10 revs on a bigger wheel is actually faster.

=more speeding fines
 

loquasagacious

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Do the maths.

When you increase wheel diamter you decrease tyre sidewall height (eg use lower profile tyres) - this ensures that A your new wheels fit and B that the total diameter (and thus circumference) is maintained from stock which means no speedo error.

Read the thread before posting - this exact issue was discussed 11 days ago.
 

loquasagacious

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The article does have some flaws.

Everything is a tradeoff:

eg. When you fit a new air filter the trade-off is the more air it lets in (thus more power) the more crap it lets in (thus increased engine wear).

I find the simplest way of thinking of performance mods is:

Performance = handling + power to weight eg if you improve either you improve performance.

Power = air + fuel + spark eg increase these and you increase power and hence performance.

From this standpoint we can see:

Decreasing weight is the cheapest performance mod.
Improving handling is crucially important in improving overall performance.
Overall performance is a product of many factors.

For engineering reasons the best way to improve power is to improve air (the engine basically being an air-pump). Fliters, CAI, turbos, porting, etc is all about this.
 

petar13

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The site focuses on the CA20LET (Calibra Turbo 2.0L) engine, and it offers a lot of information on various upgrades (which can be applied to most cars) - all written from an engineering perspective (Fuelling, Ignition, so on). It's quite informative.

Power = air + fuel + spark eg increase these and you increase power and hence performance.
I think you should also add 'Reciprocating Weight' to your Power equation. And maybe 'Rev Limit'. Both are quite crucial for the power recipe.
 
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