It has been a while in the build, but Carolyn Hayes’s LH Torana is ready to make it’s public debut at Street Machine Summernats 35.

Carolyn was one of our OG Drag Challenge combatants back in 2014 in her previous Torana, which ran a staunch, naturally aspirated small-block. But with her husband Mark Hayes being a devout nitrous man, it should come as no surprise to learn that Carolyn’s new combo will be helped along by a healthy shot of the good stuff.

What was the car like when you bought it, Carolyn?

It was full grandpa-spec – rust free, with a 173ci six-cylinder and a T-bar auto.

We drove straight to the Central Coast and picked it up as a fully registered and driveable street car, and drove it home with no problems. It was completely stock standard, and probably a country car, with very few dents. It was a very good starting point and it seemed a shame to take it home and cut it to pieces, but that was always the plan for the car and that’s exactly what happened.

What’s the specs on the car?

It’s a 415ci small-block Chev with a Induction Solutions billet nitrous plate. The main deal with the car is to keep it light so we can get the numbers that we we’re chasing out of a full steel street car. It’ll run a Powerglide and a nine-inch rear end with 275 pro radials for the track and 295s for the street.

We’ve kept the standard pick-up points in the rear end but with fabricated control arms and Strange coil-over shocks. It runs enlarged factory tubs, and Wilwood brakes all ’round.

How’s it going to look?

Subtle!. It’s not going to be some out-there, in-your-face, big-time race car. It’s going to be a car that people see run and say, ‘Wow, I didn’t expect that’.

Above the window line, the ’cage is tucked in behind the hoodlining and the pillars. It will be fairly invisible from the outside of the car; it will only be the intrusion bar and the taxi bar that will be able to be seen.

What kind of ET goals do you have in mind?

High eights!

Under the hood:

The 415-cuber was assembled at home by Mark and Carolyn, with machining performed by Westend Performance. Starting with a Dart block, the rotating assembly comprises a Callies crank and rods and JE slugs, with Moroso and Melling bits sharing the oiling duties.

AFR 210 heads wearing Yella Terra Platinum Rockers are used up top, along with a Holley 750 carb and an Edelbrock Super Victor manifold. Sandwiched between those is an Induction Solutions billet nitrous plate to inject the special sauce.

With hassle-free motoring at Drag Challenge the main priority for Carolyn, a Comp Cams hydraulic-roller keeps the top end happy, while the fire is lit by an MSD 6AL-2 with an MSD Power Grid controller.

“That’s what we’ll use for power management; Carolyn knows how to use it because she does the data when we race,” Mark says. “We have the same system in my race car, as well as Rob Godfrey’s car. Say no to EFI!”

What makes this combo so impressive is its simplicity: it’s a traditional small-block Chev with a hydraulic-roller camshaft, cast manifold, single carby and a basic plate nitrous system, but it makes some lofty numbers regardless.

“I also built the 383ci small-block in Alysha Teale’s Drag Challenge HQ, which has been really solid. This combo is very similar, just a little bigger,” Mark says. “Carolyn’s engine has more cubes, but the heads, carby and camshaft are all very similar between the two. Carolyn wanted a hassle-free engine; she wanted to be driving it, not working on it. There’s nothing at all exotic about it, and it makes peak power at only 6500rpm. With the gearing, converter, tyres and the weight of the car, it should be a very simple yet effective package.”

The engine made 665hp naturally aspirated and 900hp on the bottle, and with tune-ups for both pump fuel and E85, the goal is nines on the motor and mid-eights with spray.

Impressive numbers indeed for such a modest-looking, low-maintenance street engine!

UNDERCOVER

Keen to see Carolyn’s 275NOS Torana in the flesh? Us too! Head to Street Machine Summernats 35, where it will be unveiled to the world as part of the Great Meguiar’s Uncover. And note, the Great Uncover now occurs on Thursday 8 January, instead of the traditional Friday night.

But its show career will be short-lived – Drag Challenge is calling!