how to do i get featured image to display original image not resize

in your functions/portfolio-items.php

you call for the system to make a new file in the size of 480×360
but in a 4 column page the correct size is 210×158.

This is causing some issue with page load, SEO score, and browser issues

I would like this to call on the original size of uploaded image not a server reduced one. I currently upload my files at 210×158 the correct size for display

Line 25

	// get featured image
	$thumb = get_post_thumbnail_id(); 
	$image = hb_resize( $thumb, '', 480, 360, true );

Line 109

	// get featured image
	$thumb = get_post_thumbnail_id(); 
	$image = hb_resize( $thumb, '', 480, 360, true );
	$full_thumb = wp_get_attachment_image_src( get_post_thumbnail_id ( get_the_ID() ), 'original') ;

Just like the link ask for the original file i would like it to display the orig file and not make a new file at a larger size and then let the browser resize it down.

Thanks,