20's on first gen?

[slownova]

i use to be refured to as Pimp touring on here.

[Travis B]

i use to be refured to as Pimp touring on here.

well thats not all bad if it's true lol I've been called much worse

[calicraig]

I have never seen anyone speak to what the "optimum" or "maximum advisable" weight of a wheel/tire combo would be.


Isn't that the real issue here (other than how they ultimately look)?

The overall diameter or width of the tire doesn't seem to be the issue. That is generally the biggest you can fit and since a 265 is a 265 whether it is 18" or 20",,,,,,

There could be a sidewall issue, but that is not what you hear when somebody says "that size (bigger than 18") will destroy your performance.

I bet there are even 18" combo's that are heavier (and thus worse for performance??) than a well selected 20" combo.

But nobody seems to talk about what the target weight should be. But I bet those Formula 1 guys figure that out...

Am I off base?

Let a brotha' know.

For the record I am looking for 20's that aren't purely Bling Bling,,,but I will never race my convertible. And I agree that some of these wheel combo's are ugly if they show puny brakes or the car is dumped over the top of them.

[baz67]

Calicraig,

This has been discussed before. It has been a while, but if you did some searching I am sure you could did it up. A few months ago Johnny Hunkins wrote his editorial about this very subject.

The glaring pitfall of larger diameter rims for performance is the larger polar moment of inertia. I am sure there are 18s that are heavier than 20s, but not if the material they are made of is the same. A 20" billet Al wheel will outweigh a 18" billet Al wheel everytime and twice on Sunday. A 20" forged Al wheel could weight about the same and a 18" billet Al wheel. I am not sure. It really does not matter. If they weigh the same and have the same tires the 18s will outperform the 20s purely due to the different polar moments between the two.

If you like the look of the 20s then by all means get them. It is not the look that I care for, but that is just me. Just do not think that bigger is better for perfomance in this case.

[Steve1968LS2]

February issue of PHR has a story on Moment Of Inertia.. It's written by Vizard so you know it's good.. touches on flywheels mostly but also discusses wheels.

[Steve1968LS2]

I have never seen anyone speak to what the "optimum" or "maximum advisable" weight of a wheel/tire combo would be.


Isn't that the real issue here (other than how they ultimately look)?

The overall diameter or width of the tire doesn't seem to be the issue. That is generally the biggest you can fit and since a 265 is a 265 whether it is 18" or 20",,,,,,

There could be a sidewall issue, but that is not what you hear when somebody says "that size (bigger than 18") will destroy your performance.

I bet there are even 18" combo's that are heavier (and thus worse for performance??) than a well selected 20" combo.

But nobody seems to talk about what the target weight should be. But I bet those Formula 1 guys figure that out...

Am I off base?

Let a brotha' know.

For the record I am looking for 20's that aren't purely Bling Bling,,,but I will never race my convertible. And I agree that some of these wheel combo's are ugly if they show puny brakes or the car is dumped over the top of them.

It's not the weight of the wheel.. it is how far that weight is from the center of the wheel. As the weight moves away from the hub it's effect is exponential.

It's ok to go with 20's if that is what you like, the important part is to have a firm understanding of the forces involved so that you know what you are compromising from a performance standpoint.

[Garymac69]

I just saw the first picture of a '69 with 20's that looks great, it makes me wish I had chose them vs my 18's. Check out the black '69 in the latest "Chevy Rumble" magazine. Those TT's with grey spokes look so good!

[calicraig]

I also love that sticky with the wheel weights posted,,,,

Food for thought. At least you guys are giving actual technical answers instead of just dismissing that approach as "stoopid". I saw that alot on TEAM CAMARO.

So basically the barrel of the larger (20") rim will account for an expediential increase in rotating mass being farther away from the center would cause the increase strain on braking capability, as well as a "pushing" affect on the suspension set up?

That my friends is some major MOO GOO GUI PAN.... I am full of it...Having a great day hangin' with you guys....

[OneslowZ28]

i would have to say the new vipers have the performance aspects down pretty well. im looking at putting my second gen on a 18/19 combo. now i don't think anyone can say they don't look good with the larger (19") rims. i know we are talking about old school cars with "dubs" but is not the point of pro-tourning to mix old and new?? It always comes down to personal preference you like it, put it on and the hell with everyone else.


As for the rim weight issues.....add more power and the issue is gone

[Steve1968LS2]

So basically the barrel of the larger (20") rim will account for an expediential increase in rotating mass being farther away from the center would cause the increase strain on braking capability, as well as a "pushing" affect on the suspension set up?
....

Yes.. as the mass moves farther from the center of hte hub it has a greater affect on braking and overall performance.. There is a good story in the Feb issue of PHR on "moment of inertia"..

Puttion on 20's is NOT stupid, it's a choice and so long as you make an informed choice then all the better. The problem comes when people put on 20's (or bigger) and have no idea that this will hurt thier performance. So long as you know the pros and cons then more power to ya

[Steve1968LS2]

i would have to say the new vipers have the performance aspects down pretty well. im looking at putting my second gen on a 18/19 combo. now i don't think anyone can say they don't look good with the larger (19") rims. i know we are talking about old school cars with "dubs" but is not the point of pro-tourning to mix old and new?? It always comes down to personal preference you like it, put it on and the hell with everyone else.


As for the rim weight issues.....add more power and the issue is gone

More power won't make your car stop better.. and the point is that even a modern viper would perform better with smaller wheels, it's physics.. They went with 19's cause it looks better and lets face it, most people with new cars are NOT going to take them to the track or car about being a second or two slower on a road track.

Build what you like but know what you are building..

[andrewb70]

It's not the weight of the wheel.. it is how far that weight is from the center of the wheel. As the weight moves away from the hub it's effect is exponential.

Wheel weight is only a small part. The major issue is the tire weight combined with the diameter.

Andrew

[Steve1968LS2]

Wheel weight is only a small part. The major issue is the tire weight combined with the diameter.

Andrew

Well we were talking wheels.. but yes.. all the weight is worse the farther it gets from the hub.. bub.. lol

[hotroddr]

I havent read all the posts here yet but from what I have read I felt compelled to take a stab at the ol polar moment of inertia thing. Your 18" wheel/tire and your 20" wheel/tire could weigh exactly the same but since the 20"er has a bigger diameter, meaning more weight is farther from the center, it will take more force to change its velocity, whether accellerating or braking. Take for example your trusty pneumatic cut off tool. With a new disc in all its 3" glory it spins up slower than the 1" worn out disc you just switched from. same goes for your wheels, it works both ways slowing down and speeding up. Basically Moment of inertia is the ability of a body to resist or store energy that would cause that body to rotate, not by friction, but by weight and its distance from the point that the body rotates about. Correct me if Im wrong here....and if I am thats really scary because I just took a class on this.

That being said. 20" wheels will look killer if done right, but the added diameter will tend to hurt performance in braking and accelleration, and your car will coast longer when you let off the gas while cruising. This probably isnt a concern on a street car because you are concerned about looks not how to beat the other guys lap time.
Hopefully this all made sense...We are not trying to change the subject about whether or not your wheels will fit, we just want you to understand what all will be influenced by this change in wheel diameter

*EDIT-now that I actually have read all posts here, I know that my information was mostly repeat...sorry...I learned my lesson

[andrewb70]

Well we were talking wheels.. but yes.. all the weight is worse the farther it gets from the hub.. bub.. lol

Since you can't really run wheels without tires its probably best to consider them as a package.

Andrew

[Steve1968LS2]

Since you can't really run wheels without tires its probably best to consider them as a package.

Andrew

One could also say that since you can't run one without the other that it sould be obvious about the tires.. :p

[andrewb70]

One could also say that since you can't run one without the other that it sould be obvious about the tires.. :p

It should be obvious, but many times people focus on wheel weight and forget to look at the actual tire weight.

Andrew

[GRider68]

Does any one out there still have any pictures or a link to Scott Whidby's black camaro with 22"?

[robbie9999]

not into camero s but this guy when nuts on the wheels

wondering what kind they are - intro custom wheels v rod 5 ?

[USAZR1]

I think I may be the original poser! YES!!!!!!!!!! In your faces!!!
Vintage 1999 baby! 18's and 20's on a first gen. Top that!!!

http://home.earthlink.net/imagelib/s...target=tlx_new

They spelled my name wrong. But that was probably a good thing. As I'm sure people were trying to hunt me down and castrate me for such an ungodly act!

I installed some 18x8 & 20x10 TT II's with Michelin Pilots on my former 68 El Camino in early 1998. Took me four months just to find some rear tires. Click on my sig and scroll down to see some photos of the car that we owned for 32 years. With Global West,Koni, & Hotchkis suspension parts and four wheel Baer brakes,it was a good start to another protouring ride. Unfortunately,my wife suffered a stroke later that year and I ended up having to sell it to pay off some huge medical debts.