World’s first LT1-swapped Holden!

Corey Edwards is sick of LS swaps, so he chucked a new-age LT1 in his HT Premier for a world-first conversion

Photographers: Chris Thorogood, Michelle Porobic, Luke Hunter

The LT is GM’s successor to the virtually discontinued but beloved LS engine platform. The LS has been a wildly popular V8 conversion choice for many years now, so why aren’t we seeing LTs used the same way?

Availability of engines and parts would seem to be the main issues, but that didn’t stop Corey Edwards from being the first in the country (and therefore the world) to stab an LT1 in a Holden: his 1969 HT Premier.

“I’ve played with LS engines plenty of times, and I wanted to do something different,” he says. “The LT looked like a better platform than the LS, and PPS Imports had some LT1s they couldn’t get rid of, so I scored two engines for $3000.”

Corey’s HT had a small-block Chev in it, so he cut up those mounts and rejigged them to suit the LT. “LS mounts don’t work, and I had to modify the sump to clear the rack conversion the car has,” he says. “LS header flanges are different as well, so those had to be custom made also.”

Standard, the LT runs direct fuel injection into the heads, similar to a diesel. To get around that, Corey used a Holley Hi-Ram intake that converts the fuel system with a pair of rails back into the intake.

For engine management, Corey says it’s super simple to convert the LT to LS brains. “The cam and crank triggers are the same as the LS, just with different plugs,” he says. “So you just change those, adapt a loom super easily, and mine is running an LS3 ECU. 

“That’s one of the major benefits to the LT – being able to adapt readily available LS ECUs and wiring so easily.”

Corey’s LT1 still runs a stock bottom end, albeit refreshed. Upgrades include a pair of Higgins heads and a BTR camshaft. “People don’t realise how different these LTs are to an LS, and there’s no parts here in Australia,” he says. “It has LS lifters, but the heads run reverse valves to an LS; LS bearings don’t fit – the list goes on.”

The LT1 in Corey’s HT made 470rwhp through its Turbo 400 ’box and nine-inch diff, and it has run a PB of 11.43@124mph over the quarter. “It has a lazy 60-foot off the footbrake, so it’ll go quicker if it can get out better,” he says.

The combo debuted fresh at the Hardass 1000 in March this year, successfully completing the whole event. “I finished the car on Friday, got it tuned, and the first test drive was to Heathcote for sign-in day that Sunday before racing on Monday,” he says. “We did the three-dayer as well, where it did a 7.20 at Wilby’s eighth-mile.”

Corey has a special history with the HT, too. Growing up in country Victoria, he serviced this very car as an apprentice, when it was still a stock six-pot.

“I was hoping to do more drag-and-drive with it this year, but I’m in the middle of setting up my own shop, TMD Auto Co, in Wodonga, so we’ll see how we go for time and funds,” Corey says. 

“I have an L8T crank, and that might go in there, and we’ll add some nitrous,” he continues. “With the bigger head bolts and flow, the LT is definitely a better platform to me than the LS, so I’m keen to see where it can go.”