Off the top of my head I believe the one of the loudest cars in Iowa would have been Al Laake with his Super Street 1-2 nw World Championship van, with an SPL of 162. Terry Burns one of my team mates, is the street beat 2 runner up last year at USACi world finals was posting 153.7 on music in kick.
I think you will have alot of competition out of Iowa this season, my team is in the process of building a couple of cars that should have no problem being in the Mid to high 150s. Along with us, there is a couple other teams in our region that are building some very loud cars as well.
Are you building a pure spl car, or are you trying to reach the 50s on music?
Where in Iowa are you from?
Sounds like you have alot of work ahead of you, good luck.