FAST Adjustable LSXR (LS3) Intake Test—-Long vs. Medium vs. Short Runners. See All 14 Photos. ... Tested on our cam-only LS3, the long runners on the new FAST LSXR were the clear choice.

Fuel Air Spark Technology (FAST) has recently updated their 102mm LXSr intake manifold, and is also launching a new line of modular intake runners to be used with this two-piece intake, so LS3 ...

FAST Adjustable LSXR (long runners) See All 66 Photos. Summit price: $987. Construction: composite. ... Equipped with the short runners in the Fast LSXR intake, the LS3 really wanted to rev.