Question on wheels AFS vs C5
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Joined: Jun 2002
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From: plainview ny
Question on wheels AFS vs C5
Today I aoutocrossed my car for the first time since I upgraded my suspension and it became immediately appearent that my tires have become the weakest link. So it is time to upgrade. I do not want to keep the same size wheels. I am debating between using C5 rims (thick 5 spoke) or A-mold replicas 9.5" front and 11"rear (A-molds are out of budget). As for tires I am partial to the michilin pilot sports but I have a few questions about the wheels.
A-mold replicas seem significantly heavier than the stock wheels. Will the added weight have a significant effect on acceleration or handeling? remember my motivation behind the is improved performance not improved looks (although that does not hurt).
C5 wheels: What size are the stock rims? what size tire will fit? Will they fit without spacers? Is the overall height of the tire different than the sawblades?
Thanks for you imput!!
_Brian
A-mold replicas seem significantly heavier than the stock wheels. Will the added weight have a significant effect on acceleration or handeling? remember my motivation behind the is improved performance not improved looks (although that does not hurt).
C5 wheels: What size are the stock rims? what size tire will fit? Will they fit without spacers? Is the overall height of the tire different than the sawblades?
Thanks for you imput!!
_Brian
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Joined: Jun 2002
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From: plainview ny
Re: Question on wheels AFS vs C5 (BrianS)
I konw many people are using the AFS replicas... I would really like to know if they noticed any negative impact in handeling or acceleration due to weight.
_Brian
_Brian
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From: Chandler AZ
Re: Question on wheels AFS vs C5 (BrianS)
C5 wheels: What size are the stock rims? what size tire will fit? Will they fit without spacers? Is the overall height of the tire different than the sawblades?
Here's what I have from memory...
Base C5:
Front - 17X8.5 - 245/40-17
Rear - 18X9.5 - 275/35-18
Z06:
Front - 17X9.5 - 265/40-17
Rear - 18X10.5 - 295/35-18
C5 rims will fit 88-96 C4's without spacers. I haven't tried rear Z06 rims on the rear of a C4 but have with 9.5 wide rims. I would think another inch might make it flush with the top of the fender. Michelin Pilot Sports are probably the best all around tire. But if you are going to get serious about auto cross I'd go with BFG's... and the Supercar's (OEM Z06) can hold their own in the twisties.
Xtreme Motorsports is having a garage sale right now... go here to take a peak:
http://forums.corvetteforum.com/zerothread?id=362506
We also sell reproduction ZR-1, chrome Z06, chrome Y2K's as well as our own XMS line. The ZR-1 rims are not yet on our website so if you are interested in them give Mike a call. We can also weigh them for you if you want. Contact info in sig :)
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Joined: Feb 2000
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From: Austin Texas
Re: Question on wheels AFS vs C5 (BrianS)
You'll need to be careful about what sizes you pick to put on your car. If they were not available on your car it will bump you to a modified class. The 11" rears were only available on the GS & CE '96 models.
As far as weight is concerned, where it really hurts you is the un-sprung weight. Think of it this way...take a 1 lb. dumbell and hold it out at arm length to your side. Move your arm up and down at a constant rate as fast as you can. Now take a 5 lb dumbell and try the same thing. It is much harder to maintain the speed.
What it ends up doing is bouncing the tire more when you go over bumps. Since the suspension needs to work harder to keep the wheel on the road you end up with the tire not in contact with the road as much. You'll not have as much traction in turns with ANY kind of ripples in the pavement.
As far as acceleration, it is the same as any other law of physics. You add more weight and you must overcome that mass to get it in motion. But in this case you have a double hit. It also affects the rotational mass of the drivetrain. The motor will not rev as fast as it used to.
In an event where the difference between 1st and 2nd can be (and usually is) hundredths or thousandths of a second apart, it can make a big difference.
[Modified by Joe90, 7:29 AM 8/12/2002]
As far as weight is concerned, where it really hurts you is the un-sprung weight. Think of it this way...take a 1 lb. dumbell and hold it out at arm length to your side. Move your arm up and down at a constant rate as fast as you can. Now take a 5 lb dumbell and try the same thing. It is much harder to maintain the speed.
What it ends up doing is bouncing the tire more when you go over bumps. Since the suspension needs to work harder to keep the wheel on the road you end up with the tire not in contact with the road as much. You'll not have as much traction in turns with ANY kind of ripples in the pavement.
As far as acceleration, it is the same as any other law of physics. You add more weight and you must overcome that mass to get it in motion. But in this case you have a double hit. It also affects the rotational mass of the drivetrain. The motor will not rev as fast as it used to.
In an event where the difference between 1st and 2nd can be (and usually is) hundredths or thousandths of a second apart, it can make a big difference.
[Modified by Joe90, 7:29 AM 8/12/2002]
