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anyone know anything about how much power is lost with defference between wheels? 19"275 to 16"205?

Think of it this way - if you were riding a bicycle which would be easier for you to turn? I can't quantify it exactly but the bigger and heavier, the worst they are. Of course the trade off is a larger contact pad means greater traction so a wheel size that put more rubber on the road (wider) will give you more traction but a bigger (e.g. 22 vs 17) is a big negative.

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the bigger wheels you have the more power you get. same with chrome. Thats why people go bigger and bigger wheels thse days....not becaues they look cool, only the cool people know they add at least 30kw for every size up. who needs bigger turbos when you can get the same power with 2" larger wheels

Thanks for your lovely comments.....i was asking a serious question....how much power is lost with big wheels as power is lost from the engine to the gearbox, diff etc....my bro reckons it will have a fairly significant effect and suggests that I change my wheels before going to get a bigger figure...

i have to change my rims for the skid pan day next weekend eventually, and at the drags i have light stock rims, thought id match power. also it aint cheating, maximising....why spend money on mods when you couldnt care less to change rims to maximise power output.

Mainly i was curious at how much power would be eaten up.....you lose quite alot from the engine to wheels and was interested where it was lost the most and where i could save it....

Smaller rims gets more power because you are effectively shortening the gearing. This is only so if the overall tyre diameter reduces as well. It's got nothing to do with weight.

To achieve a similar effect you could dyno it in 3rd gear instead of 4th.

i have to change my rims for the skid pan day next weekend eventually, and at the drags i have light stock rims, thought id match power. also it aint cheating, maximising....why spend money on mods when you couldnt care less to change rims to maximise power output.

Mainly i was curious at how much power would be eaten up.....you lose quite alot from the engine to wheels and was interested where it was lost the most and where i could save it....

hehehe.. yeah valid point!! i'll be changing my rims for drags.. will probably just get street semis for track! can't be bothered going to that extent!! :) i like just turning up, and driving straight out! :D

Small overall diameter tyres shorten your effective diff ratio which increases the tractive effort (torque..well, sort of), measured by the chassis dyno. Since HP is calculated from the 'torque' measured, power increases.

Nismo God, you have it backwards mate.

dont want to state the obviouse

but where is the farken r31 award

if your not going to have one then can i just get a prize john and call it the fatz rocs prize!

ya poofs!

I was the only R31 there last time, no competition :) I didn't even have to get on the dyno to win (well, i did, but, you know)

umm was I the only person who spotted lingeringsoul was being damn funny.

Dyno days always seem to bring out everyone's serious/competitive side :)

silly ain't it!

and lol @ 2rismo. "VTEC y0"

I won't be running, I can't afford it. Well, if anyone wants to pay me, I'll actually run on the dyno rollers and see if I can make 1kW.

errmm... where would one put the temp sensor then?

Hi all.

At the dyno day, will they just be running your car on the dyno to see how much it's got at the time or will they tinker with a few of your mod's to see if they can get more out of your engine? :P:)

Hey Joeyz, they won't necesarily tinker with the car. There's generally no time.

Unless it's Ben that's running the cars up, and your name is Mona, and you say, "I don't care what it gets just make sure I beat wilch!"

Then you make close to 500rwkW with a tiny turbo.

lol

I bet my R31 makes more powah and tourqe than you James!

AND will be quicker than you!!!

Oh shit, now the thread is getting more competitive!! hahahahaha

:)

agree with Jess - Restepa ftw!




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