Rims

[BrentC4]

Yo yo.........

 

I have standard 16'' rims on the car, 17'' looks good on any car.

 

I know im being a d**s for asking, but whats the diffrence(performance wise)?

 

I'm asking cause i picked up a dice with a VW polo it was only a 1.4i he had 17'' on his car, and for some odd reason he was keeping up................that makes me worried.....

 

 

 

 

Peace out

 

BrentC4

[wozza]

Guessing you have the 1.4 or 1.6. Petrol 1.6 should have left a Polo for dead. The 92 HDI and 1.4 are about the same pace as the Polo.

 

17's might lower the acceleration a touch but I dont think its that much.

[iannez]

as long as you keep the rolling radius the same it will make no difference to the performance. this site will help show you how to work it out. http://www.dsm.org/tools/tiresize.htm

[Ronin]

If anything as long as the rolling circumference is the same, you should have better acceleration with larger alloys.

 

Less tyre flex and usually a larger "footprint on the road surface give you better grip off the mark and alloys are usually 45-55% lighter than steel wheels. This in turn increases the torque usage or the driveshafts and gearbox.

 

I remember doing rolling road tests in my friends workshop and for a daft laugh we did one with normal wheels and then alloys. I didn't believe him when he told me that it would increase bhp and torque figures at the wheels... But he was right by 3% extra on bhp and 5% on torque. Doesn't sound much does it? Think about 200+ bhp though and you get the idea.

 

Then there is the decreased braking distance and obvious handling improvements.

A lot of people neglect to think about what makes your car go faster and think automatically (engine mods)

Its all to do with how you increase the power to weight ratio and how the power is used or put down on the road.

The average engine loses about 20% of that power by the time it reaches the wheels due to mechanical drag of the gears, drive shafts and finally the wheels themselves.

 

With that in mind you have to think "how do i decrese the amount i'm losing?" and not how much extra do I need first?.

two main ways are : alloys and lightened flywheel

 

I'll put this in a cost per power, point of view.

190bhp standard exhaust..... 197 bhp full performance exhaust £450 = (4bhp / 2lb ft torque at the wheels)

or

alloys 18" and tyres to match £600........= 5.7bhp and 9.5 lbft torque at the wheels... Do the math ;)

 

Then buy both lol ;)

 

A fact that might help is... the average F1 car can deliver up to 890 bhp... Magnesium alloys superlight gear assy. and carbon brakes mean that an F1 car can put 850 bhp on the road ! Thats a lot less than 20% loss on a road car !

[wozza]

You guys seem to miss a very crucial part out in your maths...weight. Metal is heavy.

 

Go from a 16" wheel to a 17" wheel there is more weight thus more unsprung weight. The one area that is the worst area to increase weight on when it comes to vehicle performance. Any unsprung weight you can lose translates to more power at the wheels. And better braking performance and the ability to change direction better.

 

Add weight and you decrease those abilities.

 

Losses though drive train are typically 12 - 15% for FWD car. 15 - 17% for RWD and can be over 25% for AWD cars.

 

Adding bigger heavier whees = slower acceleration even if the rolling radius is the same. Due to more weight this in turn requires more force to move it thus it will decrease available power at the wheels resulting in slower acceleration.

 

If you move to a larger wheel and tyre and the rolling radius is higher your will effectively gear your car higher thus top speed increases. Same as if you go to a smaller wheel and tyre acceleration will increase top speed will drop.

 

You can however put an 18" wheel on that will be lighter than the 16" on there now but only if your willing to pay for a decent wheel. Most will be heavier than what you have now resulting in lower performance. You also have to then consider tyres which can be heavier as well.

[iannez]

we are talking about a 1.4 or a 1.6 c4 arnt we. mods like these will not be noticeable on something like these. lightening fly wheels and road wheels on small engine cars only reduces the momentum they carry making them die of quickly when going up hills. think you will lose more than you would gain by doing this.

[wozza]

If anything sticking heavy large wheels on a small engined car will have a more detrimental effect due to them not having much in the way of torque to begin with.

 

Thus not as much force to get those wheels moving. Mate of mine went from 15's to 17's on his 1.2 Punto. Acceleration went from slow to non exsistent.

 

I mean the 1.4 - 1.6 C4's are slow to begin with and adding more weight just makes things worse.

[iannez]

1.4 lx has 15" steel wheels and 1.4 vtr has 16" alloys. if you have ever removed a vtr wheel you should know how heavy they are. tbh i have never expirienced a heavier car wheel than these. way way heavier than std steel wheel. both cars have 90 bhp and both have the same 0-62 time of 12.8 sec.

[Ronin]

Lol that's what I can't understand about manufacterer's own alloys... They are so damn heavy, yet if you buy aftermarket alloys (not the cheapest ones you can find lol) they are a hell of a lot lighter... go figure! ;)

 

I just wonder what they actually make them out of and why lol :lol: :huh:

[BrentC4]

Yo People......

 

 

Thanks Alot hey, this site has helped me a sh*t Load. I've decide every mod i do to my car, ill post the suggestion.

I know its only a 1.6i but can and will dominate the 2.0i class.................

 

 

Peace Out All

[wozza]

Well the little 1.6 can make some fairly decent power with mods it could be built to rival the power of the 2.0 block it's just how much money you want to chuck at it thats an issue. There are even turbo and supercharger kits for this engine from various companies...but its a bit of a waste of cash.

[richbaker]

do ya have any 22's? i want to buy em..

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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[wozza]

A few of us have come to the conclusion that alloys are so last year. I'm now going to the SX steelies with chrome spinner wheel trims.

 

Gonna be pimp innit yo!