URBAN WARFARE
> POR440 TAKES ON DRAG CHALLENGE AND LIVES TO TELL THE TALE
Would you let two blokes take your just-finished race car on Drag Challenge? Arby did!
MORE REVS SAW ANOTHER PB WITH A 9.26, AND ADDING ANOTHER POUND OF BOOST ON THE NEXT RUN HAD US SCRAPING OUR JAWS OFF THE GROUND – 9.16@150.8MPH. KILLER!
THE 2016 Street Machine Drag Challenge seemed a long way away when work started on POR440, my turbo Ls-powered barn-find VG Valiant hardtop build. But between juggling work, family and life commitments, the time just seemed to fly by. In the end it took a year to get the car finished and running at Autotech in Canberra.
But there’s nothing like hearing your project fire to life for the first time – although a smallcube, turbocharged iron block with a baby cam was not what we were used to hearing. Little did we realise how tough that tiny mill was going to be.
Once we knew there were no oil or water leaks, the gearbox ran smoothly through the gears, the brakes were all good and the car didn’t require further significant mods or repairs, the guys at Haltech couldn’t wait to get their hands on POR440 to fine-tune the Elite-equipped, stockbottom-end 5.3.
Early dyno work (above 15lb of boost) resulted in a head gasket change from the factory-style three-layer shim gasket to a multi-layer LS9 gasket, as the engine started pushing water over this point. We persevered for a while, but with a week until Drag Challenge and a bubbling radiator, we bit the bullet and whipped the heads off. After a quick skim by Westend Performance, we cranked out some good numbers – over 700rwhp. Then it was literally straight off to the track.
At its first meeting, POR440 managed a highnine-second pass, but a slipping transbrake on the startline meant we couldn’t get the car up on boost, and the box had to be removed. It turned out the problem was a distorted governor plate that was releasing pressure.
Norm Alavanos and the boys at Northmead Auto Centre came to the rescue with a hoist and a teardown, and after a quick driveway test we headed back to Eastern Creek, just days before Drag Challenge.
With the transbrake fixed, it was a matter of getting the car off the startline. It had already run 147mph, but with a terrible 1.8sec 60-foot time.
We made the decision to not add any more boost – already at 23lb – until we had the car in the bottom 1.4s or better. We were already leaning on it, so there was no point in pushing the bottom end out of it without the chance to run a decent number first.
On the Wednesday before Drag Challenge, and with lower rear-end gearing (3.2:1 changed to 3.5) after the previous meeting, we stepped the boost up to 10lb off the startline and managed to click off a 9.7@147mph, although the 60-foot was still pretty ordinary with a 1.7.
Although the car had done a few small trips around Sydney, it really hadn’t done many road miles, and of course driving between tracks is a huge component of Drag Challenge. So a return trip to the Blue Mountains a few days before the event saw the car producing decent fuel economy – 14L/100km on the highway and 10L/100km at 60km/h around town.
Work commitments meant I couldn’t run the car myself at Drag Challenge, so I handed it over to the lads at Haltech to have a bit of fun in it for a week. After all, who better to get the combination running like a Swiss clock than their gun tuners? Haltech’s Luke Waldon and Mitch Smith prepared to put POR440 through its Drag Challenge baptism of fire, which would include 1500km of road driving and a bunch of racing.
The first two days of racing didn’t show any real improvement, although they wrestled with traction and soaring temperatures both on and off the track.
The real excitement started at the new Swan Hill track on Day Four. They bumped the boost up to 12lb off the startline. On the first pass it blew the tyres off at the 60-foot mark, but on the second pass the car responded with a 1.51sec 60-foot and clicked off a 9.40@146mph.
The big drive back to Calder for the final day’s racing went without a hitch, and at the track, cooling the car down properly between each run seemed to make a difference. The first run was 9.51@147mph. A quick check of the fuel filter showed it to be heavily blocked, but with more revs on the launch POR440 managed a 1.48sec 60-foot and a new PB of 9.38@148mph.
More revs saw another PB with a 9.26, and adding another pound of boost (14lb off the startline) on the next run had us scraping our jaws off the ground – 9.16@150.8mph. Killer!
Based on the car’s weight – at 3500-3600lb it’s no lightweight! – and mph, the stock-bottomend 5.3 is showing 986hp at the engine!
Overall, POR440’S maiden voyage at Drag Challenge was a great success. To run a 9.16 in a new car built from scratch was an excellent result.
Our original goal of putting this car into the eights on a little 235 tyre is looking good. The idea was to use technology to get the best out of a near-stock motor with 180,000 miles on the clock. What has become clear is that you really need good data to not only make the car perform but to keep the engine alive. The Haltech Elite plug-and-play ECU we used retails for $3950 and comes standard with datalogging, traction control and inputs and outputs to run all the sensors you need – driveshaft, EGT, flex fuel, boost controllers, pressure and the like.
While running a good number is important, we need to make the car competitive, and with small cubes and a large turbo there is a bit of an issue getting it up on boost when it’s hot. A smaller rear turbo housing would help, but our next step will be to add another 500rpm stall to the Dominator converter. The car does have a bump box (standard on the Elite ECU), so if we can get it up on boost faster it will eliminate some of the staging issues we suffered at the recent APSA Grand Final in Sydney.
Around the 1100hp mark is really the limit of this little engine, so before we start adding a more aggressive tune, it’d be nice to get the car into the low 1.4s/high 1.3s in the 60-foot.
Once we get the 60 down another tenth, we should be into the eights, and with a little extra boost, who knows where it will go from there!