No-lift shifting appears like a easy idea. As a substitute of lifting off the throttle whereas shifting a handbook transmission, you simply hold your proper foot planted. However there’s extra to it than that, particularly with turbocharged engines, as detailed on this video from Engineering Defined.

A handful of manufacturing automobiles have provided no-lift shifting options from the manufacturing facility, starting from the Chevrolet Cobalt SS to the present Cadillac CT4-V Blackwing.

Within the Cadillac, there’s a twin-turbocharged 3.6-liter V-6, a kind of engine the place a no-lift shift could be significantly useful for sustaining enhance. Nevertheless, if the automobile isn’t arrange for it, you additionally danger harm to the transmission. Retaining your foot on the throttle raises engine pace, placing quite a lot of further load on the clutch when its time to re-engage.

One approach to keep enhance with out permitting the engine and transmission speeds to get out of sync is by retarding the ignition. This permits for elevated exhaust strain to maintain the turbo spooled up with out spinning the crankshaft sooner. A gas cutoff ensures the engine doesn’t rev previous its redline, whereas the turbo’s waste gate is stored closed to harness the added strain being generated. 

Cadillac’s no-lift shift system additionally retains the consumption bypass valve closed. This may usually open when off throttle to forestall extra air strain from build up within the consumption and getting pushed again into the turbocharger, a phenomenon referred to as “turbo surge.”

Within the CT4-V Blackwing, each the throttle and bypass valves keep open whereas no-lift shifting, guaranteeing there’s loads of enhance able to go when the clutch re-engages.

The Cadillac CT5-V Blackwing additionally has no-lift shifting, however that seemingly produces much less profit with the bigger sedan’s supercharged 6.2-liter V-8 as a result of there are not any turbos to maintain spooled up. But it surely does imply you may hold your proper foot down whereas working by the automobiles, which is cool it doesn’t matter what engine you’ve got.

This text was initially printed by Motor Authority, an editorial companion of ClassicCars.com