How to stop images from resizing after upload

I want the images on this category page to be up to 510 x 510 but due to woocommerce / storefront resizing images 324 x 324 is the largest intrinsic value I can get.
I have found about going into settings media and changing the values there or even changing them to zeros. I have also added remove_image_size(‘thumbnail’) to my functions.php file. after I make my changes I delete and then re upload a category image for testing but nothing seems to work.
How can I make it so that woocommerce does not alter the intrinsic size of my images.

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