Just what the topic says. I'm curious, when updating my look with custom wheels, if I'll see a huge drop in performance if I go with 22 lb 18's instead of 18lb. I know some of us have heavy-ass rims, so what's the concensus?

I've heard lightened wheels often compared to a lightened flywheel performance wise.



Obviously it's rotating weight so your actally take off will be affected, but once your going it won't make a huge difference.



Something that no one ever takes into account is the weight of the tire as well. That is a huge factor due to the face that the tire is farther from the center of rotation that the wheel is.

yeah, I've resolved that I will sacrifice acceleration with larger wheels. Initially I was looking for 17-18lb 18" wheels (expensive) because everyone and their mom was getting made fun of for buying heavy wheels. Then I saw them drooling over some Fiskes and SSR's that came in at 28+lbs. I decided that for daily driving, I can afford moderate bling and sacrifice a little performance.

yeah it really depends what you want to do with the car, If you street race a lot. It might be worth giving up a little bling for some acceloration. But if you pimp most of the time and race a little, blinging rims really make the rx7's look good.



I'm going all out tho with my car, max performance. Took out a/c and everything, so it's not exactley the ideal daily driver.



woooooooooooooooooooooooooooooooooo I'm drunk

Tire weight is crazy man.. Supposedly the BBS rims on the vert wiegh 12 pounds.. but with tires the wheel is like 26 pounds..

i dont get it why am i here, where is here?



mike

ah ok now that we know where we are, um yeah tire wieght.

its not a huge deal on the street as long as you're not making big changes



mike

heavier wheels/tires have a large impact on handling not just straight line acceleration.



it's unsprung weight.



Its weird to me to compare heavy wheels/tires to heavy flywheels, the wheels are after the transmission and rear end. In the lower gears, your engine is accelerating at a very high rate, so the mass it must accelerate (rotors, eccentric shaft, flywheel, clutch disc, pressure plate..) is a big factor. The mass of the wheels is much less significant in this respect, as it's after you have the torque multiplcation of the transmission and gearbox helping. In 1st gear, the engine is spinning (and accelerating) at a much higher rate than the wheels. In the higher gears, it's a closer match but at that speed aerodynamic drag is the major issue. You can, however, see why the flywheel weight is such an issue.





I would be more concerned with it from a handling perspective, especially considering it's a rx-7, not a camaro. (something you would actually be sane to consider taking to a road course)

yeah, you have to take into account that a lighter rim/tire setup will respond much quicker with your suspension. If you have a 55 lb weight on each of your hubs, your shocks and springs won't perform nearly as well as if it's a 35 lb setup. The more your can help the shocks do their job, the more the tire is stuck to the road = more traction



also I use the vert bbs rims with proxy ra1's for my autox tires, and let me tell you, those are rediculously light rims. When me and jims picked them up we laughed for like 5 minutes. Even with the sticky tires on them, I was able to spin all the way through first gear with them.



K I changed my mind, lightweight tires/rims, make a big difference.

I feel ya brother



cheers