My wheel comparison: stock 20's vs. stock (1LT) aluminum 18's: A writeup

[ALLTRBO]

So, as you may have read in other threads, I bought a 1LT/RS manual a few weeks ago, but I wanted the stock 1LT "Bavarian Silver" IROC-Z styled 18's for many reasons, mostly performance, instead of the Midnight Silver RS package 20's that I got. So, I bought a complete set of the 18's and swapped them on today.
This is going from the heaviest regular production 5th gen wheels to the lightest production 5th gen wheels.

Here's my take on the difference wheel weights can make to the performance of our cars.

Weights:
The Wiki info is very close. I weighed all of mine on an accurate scale.
The 20" rear combo wheel/tire/sensor weighs 68.5 lbs each! That's massive!
The 20" front combo wheel/tire/sensor weighs 64 lbs. each. Not much better!
The total 20" combined weight for all 4 = 265 lbs.

The 1LT aluminum 18" wheel/tire/sensor combos each weigh 54 lbs., for a combined total of 216 lbs.

That's a loss of 49 lbs. Not only in overall weight, but in unsprung weight and in rotational weight. In wheel speak, that's a huge difference all around!

So... All in all I am very impressed with the difference. I was hoping for a noticeable improvement, and it's even better than I expected!

The car feels much lighter on its feet (almost literally) in every way. I can now see why the mag testers felt that the 20's have a 'soggier' steering feedback than these 18's, it's easier to turn in and soaks up the bumps with more control, and it really does make me feel more 'connected' to the road. The whole car just feels lighter and more willing to do what I tell it to. Basically, it just flat-out handles better.
it has less of a 'heavy highway cruiser' feel and more of a 'large but responsive sportscar' feel, but it rides even smoother as well!

As far as acceleration improvement, it's hard to judge so far because tonight is the coldest night since I've owned the car, and it is definitely more powerful as it would be anyway, but I'm betting a lot of that does come from the 49 lb. rotational weight loss (especially at higher speeds). Time will tell. Similar with a braking improvement, I never tested the braking limits of the Perellis, but the car seems more eager to slow-up a bit now.

These are still the stock 245/55/18 all-season BFG's all around, but they hold the road better than I expected. While I never fully tested the limits of the stock 20" Perellis, I could tell that the car wasn't as balanced. This car feels very well balanced now, just from a few very spirited corners I feel that the car doesn't want to push as badly, and it'll let me kick out the rear at just the right time on a transition. That has to do with the even widths all around, and the roughly even weight distribution of the car.

But you're saying "I need the straight line traction of the 275's to get off the line!" Well, even though the stock V6 will light up the stock BFG's with ease, it's not as bad as you think. The sidewalls are much taller on these 18's, and therefore more pliable. Upon the weight transfer at launch, more of a contact patch grabs the pavement. The 20's are quite stiff and unforgiving there. No doubt, though, that the stock Perellis are stickier.

As far as these tires being all-season non-performers, there aren't any performance choices in the stock size. However, Nitto makes some good ones in a 255/55/18, which will fit these wheels just fine, give a bit more width, and a slightly taller sidewall (less than .25" taller, almost exactly the total diameter of the 20's when you take into account the slight sidewall flex increase over the 20's... perfect). Not to mention that the Nittos are stickier than the stock Perellis anyway.

Still not enough traction? Say you have a really hot turbo LLT (I'll get there one day!) or you even want to do this with your torquey LS3. It's easy and safe to get the wheels widened at a good shop and slap on various width tires. You're adding some weight back in at this point, but not nearly as much as the stocker 20's. Those things are monstrously heavy, and that weight is all to the outside making things worse. Comparing the 18's in the same width with the same model of tire, you'll hook up better on the 18's, and that's why you don't see many drag racers with huge wheel diameters, heh.

This is all with the stock option wheels, and honestly I love their looks with slight appearance mods (I'm an IROC-Z nut... just sold my '90 6-speed twin-turbo 350 IROC-Z to help get this 'reliable' but still fun car as a DD. :( )

Overall, no more doubt in my mind, the heavy stock 20's are for show. They do look good. If you want them because they look good, more power to you, that's your cup of tea. Just realize that you're giving up a lot of available extra performance. You can go with nice aftermarket and possibly even lighter 18's probably, but I'm super-happy with the 1LT wheels with new tires and slight appearance mods. It's an easy and cheap way to make the car perform more like I think it should.
So... Go get the 18's and Nittos and go to town with you new-found performance! Or, just get a stock 1LT, upgrade the tires, and have fun.
Mild lowering with a performace aligment will do you one better, and should still ride smooth. I'm really thinking that, as heavy as these things are, we can easily outhandle the widely-touted 2011 Mustang V6's 'amazing' handling (for a solid rear axle) very easily and without spending much money.

If you really just can't stand the looks, I'm going to do some things to make these look a bit better, here's my poor PS of the pre-production tester (I lowered it about an inch, too). They really need some satin black contrast like this to look right (and to appear bigger) IMO. Easy mods:



Or just go with the quality aftermarket lightweight route, but go smaller or go home! (home to the car shows that is, hehe)

Lemme know whatcha think.

[oldfriend]

So know what are you going to do with the original ones ?

[Doc]

That's a nice wheel design and a nice retro look. You're spot on with your reasoning for performance. I got rid of my 20's on my SS and went with 3-piece forged 19's that weigh about what your 18's weigh.

And you're right; you DO notice the difference in performance and handling. Now get the Pedder's Street performance suspension package with their bushing replacements and you'll be amazed at how it transforms the car's handling. It doesn't feel connected, it feels 'glued' to the road and is such a blast to drive.

Reducing unsprung rotational weight is a superb way to improve the performance in just about every way.

[ALLTRBO]

Originally Posted by oldfriend

So know what are you going to do with the original ones ?

I'm going to trade them for another set of the same 18's plus $400. A forum member plans to make a road trip out here for the swap this weekend.

Then I'm going to swap those perfect 18's onto my car, then widen two of the current less-than-perfect ones for the rear probably to 8.5" and put some performance 275's on with the correct aspect ratio (I forgot what I figured out will work, and what exists, but close to that), and I'm also going to put some of the same type 255/55's on the front, and then I'm going to have them painted a really nice bright silver metallic and I'll do my subtle but effective black trim appearance mods. That way I'll have a nice stock winter setup and an awesome summer setup.

If that doesn't pan out, then I'll sell the whole complete set for $1200 (they have only 1275 miles on them), and I'll do the same to the 18's I have now, it'll just take longer (gotta have a running DD, need to fix my beater truck). Or I'll trade +cash to someone else and do the same as above. Whichever comes first. I really think the guy wants these badly, though.

To keep the balance, I'll add a (dirt cheap, I might add) SS rear sway bar to (hopefully) keep the cornering balance I have now, which is quite honestly about perfect! Oh, and to round it out I'm going with the simple Eibach Pro-Kit V6 lowering springs, which are 1" in the front and 1.4" in the rear. Hopefully I won't need to upgrade the shocks because these springs are pretty light as far as stiffer lowering springs go.

That's the extent I'm going to go with it because it's my daily driver, and I'm building a sub-3000lb 600hp capable mid-engine '88 Fiero GT turbo that should run circles around most any Camaro without blinking. That's why I didn't get an SS in the first place. This V6 Camaro is a total blast to drive even without 100 more hp! (and it weighs less already). That Fiero is going to be a street legal track-day killer.

Doc, I knew there had to be some lightweight aftermarket large-wheel options (I'm used to 17's being the largest wheels I've dealt with), you pay for what you get though. I bet they're sweet wheels. Do you have any pics?
I would like to go all out on the Camaro, but I won't for the aforementioned reasons. I like a very sporty, balanced ride, but for a DD I want to keep it pretty smooth still, and the 'real' car money is going into the Fiero.

Once the warranty is out I'm going with a bolt-on STS turbo kit, they should be quite proven (or disproven) by then, and shouldn't add any weight considering how much the stock V6 mufflers that it replaces weigh. ~400whp with a great handling ~3700lb car with IRS that gets 30mpg on the highway and looks sweet as hell to boot will be a fine daily driver.

That being said, I wouldn't mind taking a spin in an all-out SS anyway.

Ahh, car times are getting good again (it's just too bad that I had to wreck my '08 ZX-10R from a stupid, painful low-speed roundabout misjudgement to get where I'm at now. Ah well, I did the two-wheel mind-bending (literally) literbike performance thing, I guess it was time to move on (and finish my custom '85 Kawasaki 750 turbo instead)

Darnit, there I go again. If anyone thinks I talk (type) too much, just let me know.
G'night all.

[ALLTRBO]

Oh one more thing... Here's an example of my inspiration for sticking with these awesome looking wheels when done right. 18's look a whole lot bigger on a thirdgen, huh?:

[BackinBlackSS/RS]

Dude, they look great! Yes, you can really put some words down.

[ron10]

very nice.

[Doc]

Originally Posted by ALLTRBO

I'm going to trade them for another set of the same 18's plus $400. A forum member plans to make a road trip out here for the swap this weekend.

Then I'm going to swap those perfect 18's onto my car, then widen two of the current less-than-perfect ones for the rear probably to 8.5" and put some performance 275's on with the correct aspect ratio (I forgot what I figured out will work, and what exists, but close to that), and I'm also going to put some of the same type 255/55's on the front, and then I'm going to have them painted a really nice bright silver metallic and I'll do my subtle but effective black trim appearance mods. That way I'll have a nice stock winter setup and an awesome summer setup.

If that doesn't pan out, then I'll sell the whole complete set for $1200 (they have only 1275 miles on them), and I'll do the same to the 18's I have now, it'll just take longer (gotta have a running DD, need to fix my beater truck). Or I'll trade +cash to someone else and do the same as above. Whichever comes first. I really think the guy wants these badly, though.

To keep the balance, I'll add a (dirt cheap, I might add) SS rear sway bar to (hopefully) keep the cornering balance I have now, which is quite honestly about perfect! Oh, and to round it out I'm going with the simple Eibach Pro-Kit V6 lowering springs, which are 1" in the front and 1.4" in the rear. Hopefully I won't need to upgrade the shocks because these springs are pretty light as far as stiffer lowering springs go.

That's the extent I'm going to go with it because it's my daily driver, and I'm building a sub-3000lb 600hp capable mid-engine '88 Fiero GT turbo that should run circles around most any Camaro without blinking. That's why I didn't get an SS in the first place. This V6 Camaro is a total blast to drive even without 100 more hp! (and it weighs less already). That Fiero is going to be a street legal track-day killer.

Doc, I knew there had to be some lightweight aftermarket large-wheel options (I'm used to 17's being the largest wheels I've dealt with), you pay for what you get though. I bet they're sweet wheels. Do you have any pics?
I would like to go all out on the Camaro, but I won't for the aforementioned reasons. I like a very sporty, balanced ride, but for a DD I want to keep it pretty smooth still, and the 'real' car money is going into the Fiero.

Once the warranty is out I'm going with a bolt-on STS turbo kit, they should be quite proven (or disproven) by then, and shouldn't add any weight considering how much the stock V6 mufflers that it replaces weigh. ~400whp with a great handling ~3700lb car with IRS that gets 30mpg on the highway and looks sweet as hell to boot will be a fine daily driver.

That being said, I wouldn't mind taking a spin in an all-out SS anyway.

Ahh, car times are getting good again (it's just too bad that I had to wreck my '08 ZX-10R from a stupid, painful low-speed roundabout misjudgement to get where I'm at now. Ah well, I did the two-wheel mind-bending (literally) literbike performance thing, I guess it was time to move on (and finish my custom '85 Kawasaki 750 turbo instead)

Darnit, there I go again. If anyone thinks I talk (type) too much, just let me know.
G'night all.

They're by Nutek; 19 x 9.5" and custom painted. I'm going to be going for a Blue Angels color scheme and I'm almost ready to get paint accents done on the car.

[ALLTRBO]

Sweet! The Blue Angels have always been my favorite, even well before I served for 5-years in the Navy (one of which was at their home-base in Pensacola, FL). Your colors aren't exact, but I'll cut you some slack because you have a badarse Camaro anyway. Close enough.
I've long wanted to do a Blue Angels themed car, but I can't seem to get away from a clean and smooth black or bright-blue car.

Is there an build thread that you have so I can follow along with and read about your mods?

[redman]

Agree they might be a bit zippier with the lighter 18" inch LT1 wheels. I drove on them for the last 6 months. But the 20" inch wheels seem to be so much smoother on the freeway. Once the extra weigh gets rolling it doesn't slow down as quickly. There is almost nothing that is always better than something else and this goes for unsprung weight as well!!! The 20's look way better on my car.

[ALLTRBO]

I experienced the opposite. My car feels smoother on the highway with the 18's. That has a lot to do with tire pressure and wheel balance, also. Maybe ours were on the opposite ends of 'good' for highway cruising.
Not slowing down as quickly is a drawback, IMHO. That means they won't brake as quickly either, and I feel that the 3.6 doesn't have enough engine braking in this car anyway.

Either way, these cars are great highway cruisers as well. They're comfy, quiet, and just laze along in 6th gear until you tell them otherwise. Win-win! Definitely the best Camaro ever (I've owned 7), despite the extra heft.

[Doc]

Originally Posted by ALLTRBO

Sweet! The Blue Angels have always been my favorite, even well before I served for 5-years in the Navy (one of which was at their home-base in Pensacola, FL). Your colors aren't exact, but I'll cut you some slack because you have a badarse Camaro anyway. Close enough.
I've long wanted to do a Blue Angels themed car, but I can't seem to get away from a clean and smooth black or bright-blue car.

Is there an build thread that you have so I can follow along with and read about your mods?

Yeah I do have a build thread but I haven't updated it in a few months. Still waiting on the rear rotors and 1-piece CF Driveshaft but the mechanical mods are almost done. Now it's time for paint mods.

Here's the link to my journal thread:

http://www.camaro5.com/forums/showthread.php?t=45165

[Mr Twisty]

Great info!