I do agree, there is an air leak,I don’t know Indy, it’s a speed density car, so there’s a good chance it hasn’t been modified at all.
No need to play with the throttle stop if nobody modified it. Not that you can really modify anything on SD to begin with, 🤷🏻♂️
I still say there’s a vacuum leak.
but people seem to always play with that stop, cant help themselves