434-cube LS Next – Mill of the Month

The vast majority of big-power LS engines rely on some form of artificial aspiration to make grunt, so it’s easy to forget that these mills can be pretty handy in all-motor trim


This example was pieced together by Troy from Warspeed, and it’s essentially a full-effort, naturally aspirated deal. It uses a Dart SHP LS Next block, with a 4.155-inch bore and four-inch stroke to arrive at a capacity of 434 cubic inches.

This article was first published in the September 2019 issue of Street Machine

The rotating assembly consists of a K1 steel crank and K1 6.125in H-beam rods topped with custom CP pistons. A lofty compression ratio of 15.8:1 means that the engine, much like my good self, is alcohol dependent.

The camshaft is a big ’un – a custom grind from Comp with duration in the realm of 270 degrees at 50thou, and total lift of .800in. Troy expects it’ll spin to around 8500rpm as a result. Morel lifters send the bump skyward via Manton pushrods to T&D rockers, which act upon REV stainless valves with PAC springs. The heads are CNC-ported CID LS7-style units.

It’s a fearsome-looking thing too, topped with a towering Pro Billet intake manifold and an Enderle Bug Catcher, which has been outfitted with barn door-style butterflies by Joe Blo. The engine bucks the trend of EFI components hidden inside a hat, instead retaining traditional mechanical injection with the nozzles hidden in the valley of the manifold, fuelled by an Enderle 80A pump.

A Joe Blo timing cover offers provisions for the belt-driven MSD dizzy that sparks the plugs, but it’s all timed off an MSD crank trigger mounted to the ATI balancer.

Oiling-wise, a Moroso front-hump pan will clear the front end in the VH Commodore to which the engine will be fitted, while a Melling high-pressure, standard-volume pump was utilised. “The Dart blocks have priority mains oiling, so that helps matters there,” said Troy. “The Manton pushrods used feature a 40thou restrictor at the top, which also helps control the oil and keep it around the bearings and the lifters where we want it.

“It was good to do something a little out of the ordinary, and it’ll be exciting when we dyno it,” he continued. “I enjoyed having a play with the front end and setting up the crank trigger and dizzy and getting that to work properly. It’s good to challenge yourself.”

As for power, the goal is somewhere between 870 and 900hp – anywhere north of 2hp per cubic inch, in other words. Very healthy indeed.


BLACK is the new black, if the engines to come out of Warspeed are anything to go by! Troy prides himself on the way his projects present when they leave his shop, and works with his customers to achieve a look they’re happy with. On this one, Lowe Fabrications powdercoated a bunch of hardware, while the billet rocker covers are bespoke Warspeed items by Shaun’s Custom Alloy and are anodised black. Little touches like the Motion Raceworks steam kit complete the visuals.

St Marys, NSW