[Goose17]

I bought my shelby back in September knowing little to nothing about it, the dealership said it was completely stock, I knew that wasnt true based off the K&N CAI and the wheels from a 2007 shelby, but I wasnt sure what else was done to it, as im looking into it a lot more and wanting to mod the car, I see it has an aftermarket pulley, looks like the 2.6” with 90mm metco pulley combo, but im not 100% sure… having seen that I was kind of confused as to why it had a pulley and still passed smog when the dealership sold it to me, smogged of course. Its my understanding you need a tune to run a smaller pulley, could the dealership have dirty smogged? Or is it not tuned and running a small pulley? Either way, I want to get tuned by Lund ive been looking into it, if anyone can help me figure out if the pulley is actually a 2.6” or a 3” aftermarket lookalike much appreciated!
It is a bit dirty from bad belt slip I had, or have, im not too sure what’s going on there either, checked all pulleys and they seem good, replaced the belt and that was fine but it still chirps on a cold morning not as bad as it used to tho… California Member here! View attachment 267516

This looks like belt dust from belt slip:

 

[Goose17]

Yess thats what I thought so too, i just dont know where it’s slipping or how and how to fix it

Not sure how old your belt is, but a new heavy duty belt might do the trick. You already have an aux idler… you could adjust it for more wrap. Lastly, take a look at your tensioner. You want it to be about in the middle of its travel. If it is otherwise, your belt length is not ideal. You can also put a heavier duty tensioner on the car, which can help.