NEWS FRONT
BROADS ROMPS INTO THE 11S WITH A HARROP BLOWER ON A STOCK HOLDEN 5.0-LITRE
IN THE August issue of Street Machine, we brought you a step-by-step guide to fitting Harrop’s brand new TVS2300 Holden supercharger kit to my long-suffering LC GTR Torana. To up the degree of difficulty, we did it live in front of thousands of people at Motorex in Melbourne, and managed to have it up and running with the blower by the end of the weekend.
From there, we took the car to MPW Performance, where Adam Rogash tuned it to deliver 302rwhp – almost double the typical output of a stock injected 5.0-litre. There’s plenty more grunt to be had by treating the junkyard powerplant to some supporting modifications, but we were intrigued to see how fast we could go using a $500 potato
for an engine, aided and abetted by Harrop’s sexy blower kit.
Our first trip to Sydney Dragway was fraught with frustration. Despite the fact that the car had run beautifully on the dyno and during street testing, it started to play up on us the minute we got to the track. We chased a mystery idling problem the whole night, and although we thrashed to get it sorted, we didn’t manage to get a pass in.
During the week, my mate Liam Quirk managed to isolate an intermittent fault in the wiring for the TPS, along with a slight vacuum leak in the inlet tract. With the bugs seemingly ironed out and a bit of street time under our belts, we returned to the track the following week.
With a race weight of 2970lb and a fraction over 300hp at the tyres, we were quietly confident the car was capable of a respectable number. Adam and Luke Foley at MPW had both suggested the car had mid 11-second potential, but I’d tempered my expectations to the point where I would have been happy with a solid 12.
You can imagine my delight when it went 12.00@116mph on the first pass, with a bunch of wheelspin from the 225/50/15 drag radials on the hit, and a muffed gear shift. With a tidier launch, 11s were all but assured.
We waltzed into the 11s on the next pass, recording an 11.60@116, but still with a lazy 1.78-second short time. Figuring that
THE URGENCY WITH WHICH THE CAR LEAVES THE LINE SPEAKS VOLUMES FOR THE LOWDOWN GRUNT AND RAZOR-SHARP THROTTLE RESPONSE OFFERED UP BY THE HARROP BLOWER
a stronger burnout might whip the still-new drag radials into shape and allow a more aggressive launch, I lined the car up for our last pass of the night, drove into the water box and gave it the berries.
With some decent heat in the tyres, the old girl hooked and booked, picking up a front tyre and scooting to the 60ft in 1.55 seconds and going on to record an 11.43@116mph. Needless to say, the lads and I were pretty chuffed with that out of an unopened 5.0-litre of unknown kilometres, using pump fuel, a famously fragile 4L60 transmission, and pintsized 225-wide tyres.
The urgency with which the car leaves the line (and the fact that it’s laugh-out-loud funny to drive on the street) speaks volumes for the lowdown grunt and razor-sharp throttle response offered up by the Harrop blower, and the consistency in trap speeds (116.74, 116.76 and 116.34mph) tells us that Harrop’s water-to-air intercooler system is very efficient.
From here we’ll look at valve springs and probably a camshaft in the hunt for more grunt, which will likely see the car run into the 10s on pump fuel. It’s anyone’s guess how long the stock bottom end will hang on for, but in time we may even look at cylinder heads, a built bottom end and E85 – there’s so much potential!
In the meantime, check out episode 33 of Carnage at whichcar.com.au to see how it all s went down.