MILL OF THE MONTH

763CI BIG-BLOCK CHEV > MARK HAYES, HUNTINGWOOD, NSW

S T O R Y S C O T T T A Y L O R P H O T O M A R K H A Y E S

WE’VE seen plenty of big engines over the years, but this 763- cuber in Mark Hayes’s newest LC Torana is right up there in terms of capacity. For those who like their measurements in metric, Mark’s motor packs a whopping 12.5 litres!

“I love nitrous engines,” Mark says, “but you can only make a certain amount of power per cube – around 3hp per cubic inch – so the more cubes you’ve got the better. I built the biggest engine I could afford at 763ci.”

He kicked things off with a five-inch-bore-space Brodix block (4.84in is standard), which retains the same external dimensions of the standard tall-deck engine but allows for more cubes inside. Just the thing you need when squeezing a big-block into a tight Torana engine bay. It also means that Mark can swap his spare 648ci donk into this new car without running into clearance problems.

Down below the combo runs a Callies crank, Bill Miller aluminium conrods and 15:1-compression Arias pistons – yep, this is a serious combo. The top end sees a pair of Brodix 15-degree alloy heads with titanium valves and PSI springs, along with a custom sheet-metal alloy intake supporting a pair of 1250cfm Dominators.

Without nitrous the big-cube motor will produce 1525hp, but flick the switch and there’s three stages of nitrous available with over 750hp of additional mumbo ready to go. Add it all together and there’s at least 2275hp primed and waiting to launch this little Torana down the quarter with the kind of acceleration that will leave you breathless.

And it does launch! On its debut outing at Sydney Dragway the car ran 7.90@176mph off the bottle, and then Mark activated just one stage of nitrous and reeled off a 7.11@194mph.

Ultimately, though, he wants to go a fair bit quicker.

“The plan is to run a 6.5-second pass in Outlaw 10.5, and a 6.9 with my spare ‘small’ engine,” Mark says. “But it will probably take me three or four meetings to get comfortable in the car because I haven’t raced much since 2009.”

Just wait until he gets comfortable! s