A nitrous small-block Chev is certainly the road less travelled in this day and age – especially in a VR Commodore – but Queanbeyan Engine Service has just put the finishing touches on this epic 404ci mouse motor for a customer, and it’s ready to put the wind up the Turbo Teddies.

First published in the November 2023 issue of Street Machine

“The customer already had a small-block combo running mid-eights, and wanted to go sevens,” explains Tim Gruber from QES. “It’s for a VR Commodore radial car, and it’ll make around 850hp naturally aspirated. We’ll run 400-500hp of nitrous to start with, and there will be more available with all three kits if needed down the track.”

Tim started the build with a Dart SHP Pro block, which features a big-block cam core and Chrysler lifter bores. The crank is a Lunati 4340 3.75in stroke unit, married to Oliver Super Speedway billet rods and custom Diamond gas-ported nitrous slugs, while static compression rests at 13:1.

The heads are 13-degree Brodix castings done by NxtGen/Tremaniac Racing with the company’s own custom port and chamber design and softened chambers. They are loaded with T&D 1.75/1.70-ratio rockers and PAC springs.

“The camshaft is a billet solid-roller fully made here in Australia,” Tim says. “The billet was made by Ivan Tighe Cams in Queensland, and our own custom grind was then applied to it by Crow in Victoria.” The remainder of the valvetrain consists of Crane Ultra Pro .904 roller lifters and Trend 3/8-inch pushrods.

Up top, you’ll find a two-piece Edelbrock inlet manifold ported in-house at QES, loaded with a PDH billet carb spacer, a Pro Systems Little Monster billet 1170cfm 4150 carb, and a whole bunch of nitrous hardware.

“The nitrous system comprises a Nitrous Express two-kit plate system from the customer’s old engine, and also a Nitrous Express Piranha fogger system that we have added,” Tim explains. “The main reason for the fogger system is individual cylinder tuneability. When we start pushing hard, we can put more fuel in certain cylinders or take nitrous out of certain cylinders to make sure everything is spot-on. Also, being a radial car, three stages of nitrous gives us endless tuneability for power management, so [adding the fogger kit] was a win-win. Paired with ignition timing tuning via the MSD Grid, we have everything we need to get the car down the track.”

FLASH IN THE PAN

With VR Commodores having a front-sump oil pan configuration from factory, a dry sump oiling system was a wise investment for this combo. Tim opted for an ASR dry sump and a four-stage Moroso pump. Also note the sexy billet engine plate and NxtGen Engineering/Tremaniac Racing valve covers.

Queanbeyan Engine Service,
Queanbeyan NSW