The fact they have different part #s Tells me they wont work, but i could be wrong! The 5.8 with a blower sitting on top if it weighs more then the stock 5.0 so the spring rates will be different!
Here are both springs. GT500 on the left. If I knew the spring rates I could calculate the force at the installed height. Installed height is approx. 10.5". Free length on the GT500 is 11 5/16" approximately and the GT at 15 15/16". A difference of 4 13/16". Both springs were measured the same way so a good comparison of free length. Wire diameter on the GT500 is .650 and the GT .585. With a smaller wire and more coils the GT will be the lessor rate spring. With the GT being longer and the lessor rate the load at the 10.5" height may be the same. This would mean the car would sit at the same height with either spring. Part number on the tags for each are: GT500 = DR3V-5310-LB and the GT = BR33-5310-FB.
Yes, the GT500 are definitely stiff springs. Very harsh ride. IDs are the same. They fit but just concerned about the extra length of the GT vs. the GT500.
I had 2012 GT500 SVTPP springs and struts on my car for about 5000 miles. It was stiff, but the front sat a bit higher than the GT500 they came off of. I ended up swapping them out because the struts didn't have rebound control that I was looking for.
I have the GT springs installed now. Ride height is within 1/16" of same. Apparently load at installed height is the same so car sits same. Ride is a whole lot better!