Supercharged 400-Cube HQ Holden - Reader's Car Of The Week

Richard Wiltshire and his son built this blown HQ Holden at home from a rolling shell to tough streeter

holden hq front nw

“THE goal with this HQ was for my son and I to build a classic street machine, do all the work ourselves – particularly the engine – and have it completed in time for his Year 12 formal."

This article on Richard Wiltshire's HQ Holden was originally published in the Febuary 2018 issue of Street Machine

Holden HQ rear

"We succeeded, and with time to spare! I purchased the rolling shell online in 2011 with most of the bodywork and paint complete.

Holden HQ side

As I travel a lot for work, all the parts had to be sourced online; throughout the build I never once set foot in a performance store, but I knew my postie by name!

holden hq engine

The engine is a 400ci Dart block, with full forged internals from Scat and SRP. A pair of blower-referenced Holley 650s sit on top of the Blower Shop 6/71 supercharger. A manualised TH400 with 3500 stall and a Truetrac nine-inch get the power to the ground.

Simmons wheels

The 19x8 and 19x10 three-piece Simmons rims are the only modern touch to the car. It was only built to cruise, but on its run-in dyno tune with 5psi boost and pump gas, it ran an easy 475rwhp and over 1000Nm of torque, yet still plays nice in traffic.

Holden HQ interior

We are currently enjoying taking it around the local show circuit, as it’s a good excuse to go for a cruise, but it may see some track time in the distant future.”


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Street Machine is the bible of Aussie modified auto culture, celebrating wild muscle cars, customs and hot rods – and the incredible humans who create them.



Richard Wiltshire
Ben Hosking

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