laser1180

OK, i borrowed my friends 18" to put them on the CLP. Well it weight exact 51lbs each rim and tire combo. Well, when i drove around, the car seems lost all the punches, i sure felt its alot heavier the way the car drives, and also, i lost those "whenever i want" torque. Before, I can give gas at ANY rpm, and the car will just pull, i mean, you can feel it. But now, its sure feels like an Accord power. So are 18s SUPPOSE to slow you down alot? Cuz I heard even tho the wieght are the same, the gear ratio changed, so it will be way off..... Is this true? All the guys with 18s, what yall think????

BTW, anyone know how heavy are those CLP 16" rims and tires? Or Accord V6 rims and tires, cuz they are about the same weight! Thanks alot!

Type S

i am not sure what is the weight of the clp rims or accords.but i am sure that your friend's 18" is kind of heavy.but what makes u slow maybe the width of the tire..but u do gain a lot of traction lol..what is the width of your friend's 18" tires.and what rim is that?

laser1180

it's a 18 x 8 on a pilot sport 225/40/18

Chris

those seem kinda heavy... because i don't have much problem with 18's

Type S

yah buddy because u are having a cls

laser1180

also when i was driving, i can kinda tell the gear ratio has been changed somehow, cuz the shift point are changed and stuff... hmm... i check on the status, each rim weight 22.9lbs. So it actually not that heavy! Since the stock rims are almost 21lbs anyway! hmm, so now i wonder where could be the problem coming from!

Type S

do u also feel u need to press gas pedal harder in order to make car get moving?if so.that is only rims and tirs problems.do not worry about anything wrong with your car.

FDao

Although the 18" tire/rim combo weighs the same as the stock 16" combo, I believe the reason why your car feels slower is very likely due to rotational inertia. EricL had a link to a great program that calculates the amount of ?torque needed to spin a wheel of certain diameter/weight. It really has to do with where the weight of the wheel is distributed. If it's all centralized near the center, then acceleration may not be much affected; however, if the weight is more radial, then acceleration will be affected.

Anyone else would like to add to this.

laser1180

so i guess theres nothing i can do.... oh do you have the link for the sites? thanks alot!

laser1180

anybody?

EricL

There isn't a site with a calculator (at least not that I'm aware of), just some info in a thread:

Here is the site's link -- it is not a calculator...

http://www.acura-cl.com/forums/showt...threadid=50659


There is a link -- I got the pictures and formulas from "Fizzics Fizzle": http://library.thinkquest.org/16600/...linertia.shtml

EricL

The shift points should NOT change! If you’re talking about a change in overall diameter of the tire/wheel combo, you "actual" speed will differ from the speed on your speedometer. However, you SHOULD NOT see any change in shift points, which depend on the relationship between the gear ratios in the transmission.