How do i change max image size

[tobybird]

As dismounted stated max image size is located in the config.php file

// Image Processing Options
	// Images that exceed either dimension below will not be resized by vBulletin. If you need to resize larger images, alter these settings.
$config['Misc']['maxwidth'] = 2592;
$config['Misc']['maxheight'] = 1944;

ActiveAngler, I believe you are referring to file size not dimensions which is the the OP's concern.