Minimum System Specs

This is quoted directly from the iRacing Site:

PC Computers:
Windows XP*, Windows Vista, Windows 7, Windows 8
Intel Core 2 Duo or Athlon X2 
or higher
NVidia GeForce 7800 / ATI Radeon X1800 or above graphics adapter recommended
2 GB system RAM
6 GB free hard disk space
Microphone optional, required for voice chat
*Windows XP support will end on March 31, 2014 (Posted August 2013)

Linux Computers:
RPM-Based Linux (Ubuntu, Fedora, Redhat), etc.
Intel Core 2 Duo or Athlon X2 
or higher
NVidia GeForce 7800 / ATI Radeon X1800 or above graphics adapter recommended
2 GB system RAM
6 GB free hard disk space
Microphone optional, required for voice chat

MAC OS X Computers:
Mac OS X Snow Leopard (10.6), Lion (10.7), and Mountain Lion (10.
Macbook Pro, Macbook Air, iMac, Mac Pro, or Mac Mini
Intel HD Graphics 4000 or better
2 GB of Ram
6 GB free hard drive space
Microphone optional, required for voice chat
For more info on racing with your Mac click here
iRacing can additionally be run  with Apple’s Boot Camp utility.  For more information on installing Windows on an Apple Computer, please see your MAC user guide or this FAQ.
Controller

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Controllers:
Steering wheel, analog gamepad, joystick, mouse, or any version of Windows supporting touch screen driving.

Internet Browser Requirements:
Firefox 15, Internet Explorer 8, Google Chrome 20 or newer
Javascript enabled
Cookies enabled
Flash Player

Internet Connection Speed
DSL, Cable, Fiber, 128K or faster – Supported. Satellite is not supported.
56K dial-up minimum, Broadband (DSL or Cable) highly recommended. Satellite broadband excluded.

i will post the specs tonight of my machine that might run it just so someone who knows the comparisons a little better than i do can be sure that it will even be an option

I'll take a look

ok so here's my machine specs:

Windows 7 (64 bit)
AMD Turion 64 X2 Mobile technology TL-60
2GB installed RAM
NVIDIA GeForce 7150M/ nForce 630M

The Cpu and ram just are just above the minimum spec but the on-board graphics wouldn't run it unfortunately. Your in the same boat as sniper, he was getting something like 12 FPS.

thats what i figured :/