It was high-fives and backslaps all ’round in the Trick & Mansweto Racing team when the numbers came up. After dominating the Summernats Horsepower Heroes naturally aspirated small-block and big-block classes for the past few years, the guys went one better this time, with their naturally aspirated, 604-cube big-block Ford taking out the coveted overall Horsepower Heroes trophy at Street Machine Summernats 20.

First published in the March 2007 issue of Street Machine

To put things in context, the last aspirated engine to secure top honours was the 454 Chev in Matt Bunton’s HQ panel van, way back in 1996. Since then, outright honours have belonged to the turbocharged small-block brigade. For T&M to take the top gong with a non-boosted engine is quite an achievement. And that’s despite their numbers this year being well short of their best.

After laying down the number-one qualifying run at 974.8hp during Friday’s session, the stage was set for a thrilling showdown in Sunday’s final. It’s here the plot thickens. With more neddies under the hood than last year, T&M decided to strap the Capri on the rollers late on Saturday afternoon for another crack at a 1000+hp run. Unfortunately, the mighty Capri couldn’t eclipse Friday’s best. Then, on the way back to their stand in the Shannons pavilion, disaster struck: one of the lifters called time, smashing itself to pieces before resolutely wedging in the lifter bore.

Lesser guys would have cussed and cursed, kicked everything in sight, then loaded the wounded machine into the trailer and called it a day. Not T&M — with overall victory within reach, it was all hands on deck.

Overnight they tore the big-block down, dislodged the jammed lifter, slotted in a newie, repaired the associated damage and had everything back together and singing like a screaming banshee before Sunday morning’s highly anticipated shoot-out. And as they say, the rest is history.

Back in their Sydney workshop, it was a given that Jason Mansweto and Tristan Triccas would give everything a thorough inspection. With this in mind, Street Machine convinced the duo to let us point our cameras inside the victorious mill to see what makes it tick. Other than a quick wipe-over here and there, what you see is what they won with — nothing has been messed with.

So what does it take to make 1000rwhp with an engine that gets filled by nothing more than atmospheric pressure?

“Lots of revs, lots of cubes and plenty of horsepower smarts,” say T&M. The first two criteria are pretty straightforward — an 8700rpm ceiling and 604 cubic inches. The smarts bit is where all the engine-craft and hard yakka lies.

Normally cameras aren’t welcome prowling around high-end competition engines, especially when it comes to things like ports and combustion chambers. But the guys aren’t worried.

“Go ahead and shoot anything you like,” says Tristan. “Even if you had a head to copy, it’d still take you two years to learn how to duplicate it. Heck, it took me heaps longer than that to even get close!”

Forming the basis of this brute is a Premier Series aftermarket block manufactured by Eliminator Performance Products in the USA. While dimensionally it’s the same as a factory Ford 460, the Eliminator’s thicker cylinder walls allow it to be bored out to 4.700in. T&M has kept it to 4.625in, allowing for a couple more over-bores. Combined with a 4.5in Scat long-stroke crank, the numbers work out to the aforementioned 604 cubes.

Working upwards from there, you get to the real source of that prodigious power — the Profiler raised port heads. As good as these alloy beauties are straight out of the box, Tristan made significant improvements to their power potential, spending 30-odd hours whittling away at them with his trusty die grinder.

Moving further up, there’s an aluminium sheet-metal intake manifold supporting a pair of 1050cfm Pro System Holley Dominators that live on a staple diet of C14 race fuel. When you’re pushing the limits, however, things rarely stay the same and the inlet manifold is a classic example of ongoing development.

The guys’ original design was good for 1160hp but they felt there was more left in it. Some 60 hours later, T&M had finished cutting, bending and folding up a completely new design that features slightly shorter but bigger inlet runners. Result? Another 100hp, thanks. That’s a lot of work for an eight per cent gain! But at this level, that’s standard fare.

Although the Capri is run in essentially the same trim at the track and on the dyno, there are a couple of major differences, namely tyres, diff ratio and gearbox. On the dyno, the Capri wears 33x17x15 Mickey Thompson Sportmans pumped up to 50psi. Out come the 4.11:1 gears and in go a set of 6.55:1s, while the strip-duty two-speed Powerglide makes way for a specially-modified top loader.

“It’s all about reducing slippage,” says Jason. “A high-stall converter certainly helps ETs but it robs us of power on the dyno. Our clutch doesn’t slip.”

At the end of the day, T&M’s 604 might not be a daily driver but making well in excess of 1000hp with no forced induction or nitrous is a bloody big effort no matter which way you look at it.

Family Sport

Whether setting a new Australian Pro Street Naturally Aspirated record or smashing the field at Horsepower Heroes, Jason Mansweto and Tristan Triccas are quick to acknowledge that none of it would be possible without the considerable support and help of their committed team.

“At any event, there’s a mountain of stuff that needs to be attended to,” says Jason, “and without their efforts it would have been impossible to achieve what we’ve done.”

THE BEAST