4/71 blown EFI Holden 202

Everyone knows that if you want a load of power on the cheap, the tried-and-true Barra or LS is probably the best way to go – but where’s the fun in that?

Photographers: Shaun Tanner

Travis Fink clearly feels the same way, as for his latest street build, he decided to think out of the box and commission Adam Woods from HSD Cylinder Heads to create a wild blown 202 combo that’s capable of 400-500hp.

First published in the October 2022 issue of Street Machine

“When Trav briefed me on the engine, he said it had to look old-school with the 4/71 and the bug catcher,” Adam says. “But because it was for a street car, he wanted it to be reliable, so it had to have modern injection.”

While that brief might sound a bit outlandish to many, for the team at HSD it was more a matter of building on what they already know than starting from scratch. “We’ve been doing Holden engines for 40-odd years, so while we hadn’t done a blown motor like this before, we were able to start with something similar to one of our Group N motors and go from there,” Adam explains.

The blue-motor 202 block was half grout-filled before Adam laid in the EFI Australia billet crank, held in by girdled and ARP-studded main caps. The rest of the rotating assembly comes off-the-shelf from Spool and includes a set of the company’s H-beam rods, along with dished Ross pistons. “The cubes are still the same, and I wanted to build this engine with all off-the-shelf parts, so if we ever need to replace anything, we can just put an order in rather than having to custom-make everything,” says Adam.

The oiling system also copped a major upgrade, with an ASR sump, an HSD-fettled high-pressure oil pump, and oiling modifications within the block to increase flow and keep the 202 fully lubed up.

The head is one of HSD’s Bathurst-spec nine-port deals, with oversize valves, upgraded valve springs, Yella Terra roller rockers and a fairly aggressive flat-tappet Clive cam specced by Adam. “It’s 260 degrees duration at .050in lift, which we thought would work well for this project,” he says.

Compression is around 8.5:1 to keep the thing safe on PULP 98, and it will spin comfortably to 6000rpm.

But let’s be honest – the bit you really want us to talk about is the blower. The 4/71 sits on a CNC-machined Jeff Ramsay billet inlet manifold and is topped off with a Joe Blo bug catcher that houses the injectors for the secret-squirrel EFI system.

So far, the engine has only fired in aspirated form to bed in the flat-tappet cam, with the real tuning saved for when it’s in the car and dialled. “It ran really sweet when we bedded the cam on the engine dyno, but we’re a bit old-school here, so it sounds like Adam Rogash from MPW Performance will be tuning it in the car with the blower,” Adam says. “The pulley that’s on it now is good for around 8-10psi, which should see it make 400-500hp at the engine.”

And the car in question? It’s a sweet EK Holden ute, which Travis is hoping to have ready for Street Machine Summernats next year.

Tip your hat

The bug catcher from Joe Blo might look like old technology, but that’s not the case. “Inside the hat are the injectors run by the Haltech ECU,” says Adam. “By hiding it like that, we still keep the old-school cool look that Trav wanted. We’ve hidden all the wiring and we’re running an ICE ignition system, so it looks conventional but still works with the Haltech.”

HSD Cylinder Heads,
Moorabbin, Victoria