Ok i believe the equation is for every 10lbs you remove from the rotating mass of a car aka wheels axles, flywheel..etc. etc, you will gain a tenth of a second at the drag...

so i am trying to find the lightest wheel and tire combo, i known my stock wheels with toyo t1r radials, mine weigh 40 lbs

whats everyone elso got if you known,, and does anyone make a lightweight wheel. in 5x110

 

http://www.centerlinewheels.com/whee...ehicle&data=84

Those on top are the lightest you can find, also they are not the best looking ones. even though they can be as light as 15-16 lbs per wheel.
However im gona trade a little bit of performance for looks the ones im gona get will be 1-2 lbs heavier but looks tons better. and they are 18s.

http://www.kyowadesigns.com/KR228B.html

 

Kosei K3's in 17s are 17lbs...you MIGHT find some lighter, but 15-17 seems to be the lightest you can find easily.

 

Do you have those on your car? Cause everything I've seen/read says 15s (in the first link) won't fit over the brakes...

 

which ones, the centerlines are 17s and the 228s are 18s.

 

Alleycat, where can you buy the Kosei K3's in a 5x110 bolt pattern? I'd like a set of those.

 

NM, page froze when it was loading and only showed the first ones, which were 15s. I refreshed and saw the rest.

 

I bought mine off of someone else. I know Tire Rack carries them, I just don't know how to get them to get the right bolt pattern on there, LOL. I tried ION Redline and SAAB 9-3. I know for sure they're 5x110 though because the guy I bought them off of had them on his IRL.

 

Don't be all that concerned about unsprung weight unless you plan on taking the car to the track on a regular basis. A little heavier wheels on the street won't make a huge difference, but staying light will help ride quality, agility, steering feel, and overall braking and acceleration of the car. Anything over 17's for a small car like the Cobalt is a waste, I hear a lot of people say, "nothing smaller than 18's", LOL.

 

pull out the engine and transmission.... those are the heaviest objects in the car that are just weighing it down... see paper weights.

But really though, dont worry about making the vehicle lighter, you are NOT going to accomplish anything worth bragging about.

When choosing wheels, keep in mind, a BIGGER rim = loss of wheel horsepower (assuming you went with bigger rotors to stop the bigger wheel).

Rule of thumb, when upgrading to bigger wheels, upgrade to bigger better brakes.

 

That statement makes NO sense. In the grand scheme of things, weight is everything next to horsepower. What determines how "quick" a car is in relationship to another car is power to weight ratio.

Unsprung weight DOES make a difference. Drive a car with 25lb rims, then swap those out with a set of 15lb rims. It drives like a totally different car.

Of couse people who can't think outside a drag strip will only care about 1/4 mile times, but lighter rims shave SECONDS in any sort of racing where handling actually makes a difference...and that's definitely something "worth bragging about."

 

Amen to that!! I previously had a 2000 Mitsubishi Galant. I used progress springs to lower it and drove a couple autox's on some crappy wheels. They weighed about 25lbs or so a piece, plus the tires. Then I purchased some rota slipstreams (16" wheels that weighed about 13lbs a piece). I then ran some autox's and the handling and acceleration were noticably different.

If you have a lighter rotating mass, you have LESS inertia in the wheel which in turn allows the direction changes to be easier and quicker. So in effect lightening up the wheel will definitely give you improvements. At least to me when I had my galant it felt much lighter on its feet than before. Even with wider tires it was easier to manuever.

I am planning on waiting some until there are more choices for lightweight wheels for the cobalt. (that was just FYI. had no bearing on the actual discussion, sorry )

 

LOL race a cobalt? you kidding me? To get any horsepower worth braggin about in this car, you have to BUILD an engine for it. These ecotecs do NOT take a lot of psi before they break.

It'd cost about 5 grand to build up the engine to take horsepower over 350, then you'd have to spend the money to get the horsepower up there.

We don't need anymore posers on the road. The SS's are nothing to shout from the roof tops about either. These cars are just Saturn ion underskins... and if you look in australia, you can REALLY see where the car came from. To try to make it a horsepower king is ridiculous. Look at Holden, their Astra coupe & hatchback is what we call a cobalt. (major difference is rear end.)

So, how much more money are you going to dump into the car before realizing you could have spent the money on something brand new that can spank a cobalt? You guys spend so much money that does useless things on the vehicle. Wheels, false performance parts, ugg. Buy your self some cam blanks and grind em to your likings. You'll have more performance out of that than what most you guys will ever accomplish. How many of you guys actually know what this is?



Spend the money wisely and BUILD UP THE ENGINE!!! the ecotec needs a bit of reinforcing before you hop it up. I'd start with the crankshaft and connection rods, spend your first 5 grand there, and the engine should be strong enough to handle double digit boost numbers w/o the slightest worry. GM has a nice crank and some nice rods, worth investing in.

Ha, you have a mechanic laughing at every post you guys make.

 

Glad our posts entertain you so much. I find yours amusing as well.

Try looking PAST the straight line for a minute. I plan on being competitive with the Cobalt in road racing, which is absolutely possible, look at how well the Cobalts are doing in Grand-Am Cup racing, and with only very slight engine modifications at that.

Not everyone cares about having the biggest engine or the most horsepower. And the ones that do are the same ones that get their ass kicked by a few MCS's before they realize - "OH ****! Guess maybe I should have thought about making my car handle better instead of making it go faster in a straight line..."

The Cobalt is a 4-cyl tuner car. Doesn't mean it can't also be a race car. Again HP is only part of the equation, I never plan on taking mine over ~250 or so horsepower and that's more than enough to win races. I'm all about handling because that, to me, in the type of racing I plan on doing, is ultimately more important.

So laugh all you want, I'm entertained by your closed-mindedness towards the Cobalt (which, btw, if it's such a "horrible" performance car, why are you here anyway?).

 

the vehicle is not a performance car lol.

And when i mean build up a engine, i dont mean to make it BIGGER, i mean to make it stronger.

And kudo's to you for wanting to race on a road course. It takes the most skill out of any other type of racing. Here, i'm used to seeing all these straight line runners. The only true driving skills are on a road course. Glad I finally see one person who also likes road course racing. But sorry, 250 is just not enough if you are going onto a road course. See what you can do to get it near 275-300. If it were a road course over here, 300 isn't mearly enough.

But really though, if you are going to put it onto a road course, the stock engine just wont do (even if forced air). Its just not built strong enough. Use all the GM performance engine parts (race block, cams, con rods, crankshafts) like the grand am guys do, and you'll be set. You CAN invest the 15,000 and turn the 2.0 into a 650 hp machine... but just not wise!

I just don't see the point in investing all this money into the car. its a daily driver My toy car is a 3rd gen camaro nearly pushing 500 horsepower. Thats my project car. The cobalt, just my every day ordinary car.

My reason for being here? only place that could give info on removal of the rear deck to the speaks.

 

A Cobalt with 250 whp and a well tuned/developed suspension would own a road course...true it is not a real high performance car but it is quick enough for what most of us use them for. Anything over 250-300 whp for a FWD car on the street is getting kinda silly, the torque steer gets awful, drivability plummets...you don't need tons of power since it's a small car.

Also, I disagree about drag racing not taking any skill. I would love to see you get down the strip in a race car, you would get killed by a good driver in an identical car. I am more into track style racing but I still respect the straight line guys.

 

15s fit very EASILY over the brakes.

 

Oh really? I have next to no clearance with 16s on the car. Most people I've seen post have had to either buy spacers or machine down the front and rear calipers in order to get them on. I know I couldn't go down to 15s, but maybe someone has found some magical offset or something that would allow 15s to fit on the SS's.

 

You know, Kemo, I agree with almost everything you've said over the past few days, but somehow I still find you horribly annoying.

 

IF your talking about horsepower in Austrailia isn't it rated differently then SAE horsepower.

 

Since this post WAS about rotating mass I'll chime in on that.

I used to have some nice light 16" wheels on my cav. They felt fine and the handling was acceptable, but when I "upgraded" to 17" konig verdicts I took a gigantic hit. Keep in mind a cavalier doesnt make a ton of power, so bigger wheels alone were enough to cripple my cars acceleration and handling. Needless to say I am a supporter of the topic of this thread:

Less Rotating Mass = Faster Car

 

 

You say machine down the calipers like it is some giant chore. It is very easy and simple to grind a little bit off the calipers so that 15s clear.

 

These prices are from my sources... 1 used LSJ block = $800, wiseco pistons, IB spec rods = $1000. Installation of pistons, rods, bearings, re-installation of head and gaskets from your current motor = about $700. Yeah...5 grand minus $2500. Use the other $2500 to fab a turbo kit, which could easily include the intake mani, turbo mani, turbo, wastegate, BOV, piping, intercooler, down pipe, 3 inch exhaust, and HPTuners/ 660cc injectors. Boost the car to 20psi w/ an SC61 or better and make 400+ hp. Run low 12's, maybe even 11's if your lucky enough. So hush up and let people invest their money the way they want to.

 

I never said it was a chore, I said 15s don't fit...you disagreed, I said they do but you have to modify the vehicle to make them fit. You could have just said "They fit but you'll have to machine the calipers" instead of leaving that detail out. Not everyone wants to have to do that to force wheels on the car, especially when 16s fit with no problem what so ever.