Two Brother's Racing Muffler w/Juice Box and no lid
From Two Brothers:
43.1 hp : Slip on, Juice Box and no lid.
40.5 hp : Stock
From Two Brothers:
43.1 hp : Slip on, Juice Box and no lid.
40.5 hp : Stock

What ever your permium pump gas is will be fine.What about 92 and 91 octane?
I don't think it would be recommended to run the 12:1 on 93 with a stock cam but should be fine with a stage II or higher. Would have to actually now the cam specs but generally speaking this would be ok.Actually these big engines will need around 100 octane with a true 12:1 build depending on elevation and cam timing. The chamber doesnt have the right engineering to properly run pump at 12:1. The design is too "lazy" to be effecient enough at those levels. The 450s and crotch rockets have alot of engineering in the chambers and cam timing to run pump on 12:1 or there about depending on what brand we are talking.