I just switched from the stock turbo wheels to MSR045's, I've been told the MSRS are a couple pounds heavier. That kinda steered me away from wanting to get them but nothing else really seems to fit over the brembos so I had not choice. After doing some reading I noticed a lot of people saying that you wont actually notice much of a difference with just a couple extra pounds on each wheel especially if the rim is the same size. Now I'm a pretty spirited driver and unless im crazy, it certainly seems that my car doesnt pull as hard as it used to, I even noticed a very small decrease in braking only when braking very hard from high speeds, and for some reason it even seems less stable in hard turns. Anyone else got some input on this, could the wheel weight really make that much of a difference?

 

I had those wheels on for a month before I sold them. Pieces of caca. Everything you described and more as far as performance. Mine even had wobbles at 60-80 that wouldn't balance out. I am saving for the OZ rims that clear Brembos. They are more than twice the price of MSR but weigh less than the stockers and Im sure OZ wheels will balance just fine.

 

there are lots of wheels that fit over the brembos, all u have to do is ask and im sure a flood will come in, ill see if i can find the 17's i bought for winter, can also get them in 18s

 

i got these, but with red pinstripe. look great. just email and ask if they will work with our brembos when u are looking for some. they will let u know.

KXWheels : MSR Wheels Style 068 Black - Custom Wheels, Rims, and Tires in Canada

 

This guy put 20" rims on a solstice and dynoed it and compared it to the stock rims, he lost 2hp/4trq with the 20" rims, and this was with the 2.4L le5 engine. The dyno sheet is gone though since its an old post.

How much power do 20" wheels rob ... dyno inside - Pontiac Solstice Forum

 

Who says that anymore. Good stuff!

 

Innaccurate information. What you are gaining is rotational weight. You will not lose any direct power you are still making that power.

Example: A gutted out stock challenger At 3000lbs will still dyno the same as a stock 5000lb one. This is weight.

Now apply that theory to a wheel you are still gaining weight and rotational weight is the worst you can gain due to it having to be. You guessed it. Rotated.

To make it easier on you about every 7lbs of rotational weight is equilevent to 100lbs of standard weight.

To make it even easier to understand every 7lbs of rotational weight is roughly equilevent to 1/10th a sec in the 1/4mi.

If this were not true wheels like bogarts and etc for drag cars would never be bought.

Edit*** i just read the link most people in response are correct saying whay i am saying. It was you that was giving incorrect information and i would suggest reading the responses as there are some good examples in that thread like the glass vs plastic bottle.

 

Directly to the OP, didnt read any replies...

What you are saying makes sense. Most people wouldn't notice these changes but that is how it works.

Wheels are a double whammy as far as weight improvement/deprovement <-not a word I think

Wheels are both unsprung weight and rotational weight.

Unsprung weight not only slows the car down from a Force = Mass * Acceleration standpoint but it slows down the response of the suspension. Think of a spring with a weight at the end of it and how it moves when you excite it. Think of it now with a bigger weight.

Rotational weight, aka inertia, means more metal the engine has to spin up to speed to get the car going. Its once of those things that contributes to the difference between brake horsepower and wheel horsepower. It has the exact same effect on the brakes. Now there is more rotational inertia the brakes have to overcome to bring the car to a stop.

 

Get the Enkei EKM3's I think they are only 0.5lbs heavier than stock but they are also 0.5" wider so it's ok.

 

its all relative to the speed sir. Its almost not even comparable to talk of rotational weight vs stationary. Rotating mass exterts outbound force during the rotation, the more mass there is, the more the outbound force is amplified. Stationary weight is a different principle, given the same power, a heavier car requires more energy to move than a lighter one. More mass = more power required.

 

Have you ever seen anyone make the same power on a dyno 2 runs in a row?? I know i haven't

 

I have the OZ rims that have some mostly wore out tires on them if anyone's interested i might make a deal.