Call us crazy, but these days it seems like there are hundreds of LS cylinder heads to choose from and not enough time in the day to decide which are best. Naturally, we are a little desensitized to just how many awesome LS products are out there, but we couldn’t help but be a little giddy when we just so happened to come across Mast Motorsports and their new Str8jacket cylinder heads while perusing the halls of SEMA 2016.

Why were we so stoked you ask? Mast’s new head falls into their “race heads” category and flow close to 400 cfm on the intake side—all without canted valves and for only $1,500 per unassembled head. Are you starting to see what we were so excited about?

“We wanted to be able to offer something that wasn’t as high on the price list as our canted valve racing heads,” said Russ Lehart of Mast Motorsports. “These are going to be on par with a big-bore LS3 or LS7 head as far as price, but it’s an all-out race head as far as design goes.”

On the exhaust side of things, the Str8jacket is capable of up to 260 cfm as well—putting it’s exhaust flow numbers in direct competition with the intake side of a mild LS1 head. They come in either a “medium bore” or “large bore” version, ideal for bores in the 4.00-inch+ and 4.125-inch+ size respectively.

Strap a set of these bad boys on to a big-cube mill and watch the horsepower skyrocket. We now understand why they name them Str8jacket—because these things are straight up crazy.