In a recent story ["Gen 3 Grunt Kit" - in issue #175] we reported on Nizpro's '285' kit for Holden Gen 3 V8s. This AUS$7500 kit brings you custom extractors, exhaust, air intake and a pre-programmed MoTeC ECU to elevate the factory 225-255kW Gen 3 to 285kW at the flywheel. Starting with the factory 300kW engine brings this up to around 325kW.
Now newly introduced is Nizpro's '333' kit - this, as the name implies, generates a repeatable 333kW at the flywheel when using the 225-255kW engine as the base. Fitting the kit to a factory 300kW engine should be good for around 340kW (due to its standard machined heads, larger valves and throttle body).
Included in the 333 kit - which builds upon the 'Stage 1' 285 package - is a revised camshaft, valve springs, retainers and a double-row adjustable timing chain. The MoTeC unit is also mapped to suit.
And the price? A very reasonable AUS$2500 (plus fitment) over and above the AUS$7500 cost of the 285 kit. So in Australian dollars we're talking dead-on $10k.
Before we delve into the details of the new kit, let's briefly go over the 285 package - the necessary platform...
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ReCap - the 285 Kit
The Nizpro 285 kit has four main parts - extractors, exhaust, air intake and MoTeC ECU. The extractors are a 4>1 design, with 1 7/8-inch primaries leading into a 3-inch collector. Bolting to the extractors is a twin 3-inch stainless system, which necks down to twin 2½-inches and then merges into a single 3-inch pipe. Modified Holden cats, twin straight-through mufflers and a baffled rear muffler are fitted along the way. The air intake uses the standard airbox and filter element, but a larger diameter feed pipe. The induction pipe to the throttle is also replaced with a 4-inch diameter unit (similar to that used on the factory 300kW HSV engine).
The final part of the upgrade is a MoTeC M800 programmable ECU 'piggy-backed' onto the factory computer. The MoTeC allows the removal of the factory airflow meter (by using a MAP load sensor) as well as tune-ability for optimal fuel and ignition. Nizpro perform cylinder-specific tuning and input fuel rail pressure into the MoTeC. When applied to factory 225-255kW engines, this kit yields a repeatable 285kW at the flywheel. Applying it to the HSV 300kW engine (with its different camshaft, valves, springs, retainers, revised heads and bigger throttle body) gives around 325kW. Maximum power is limited by the standard camshaft profile and intake manifold - Nizpro's new 333 kit addresses the cam issue, while development of an improved manifold is ongoing.
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The 333 Kit...
The '333' kit builds on the ingredients of the 285 package - it adds an upgrade camshaft, valve springs, retainers, timing chain and optimised fuel and ignition programming.
After dyno testing around 12 different camshaft profiles, Nizpro selected the example that best blended maximum power, a strong torque curve and acceptable idle quality. Of course, they're not keen to give away the exact cam specs except to say it's "a higher lift version of the HSV GTS cam".
During camshaft evaluations, cam timing was tried in various positions away from the standard setting. The selected camshaft was found to perform best when retarded slightly; this is achieved by replacing the factory single-row timing chain with an adjustable RollMaster double-row kit which incorporates cam timing adjustment. This chain should also offer greater strength over the factory part.
Teaming with the revised camshaft and timing chain are different valve springs and retainers.
To accommodate the new cam profile, Nizpro tried various valve springs. The chosen springs are nothing fancy; they deliver simply a firmer rate. Other springs resulted in valve float or were too stiff - power was reduced in either instance.
To ensure drivetrain performance and durability, a full brace of titanium spring retainers is specified. In America, the selected brand of retainers is renown for their strength, and - being titanium - they keep valvetrain mass to a minimum.
To accommodate the altered breathing characteristics brought about by the new cam, the piggy-back'd MoTeC M800 ECU must also be programmed with specifically developed maps.
Air-fuel mixtures are set to hover about 13.5:1 at full load (the same as the 285 kit), but ignition timing is jigged to help pick up some of the bottom-end torque penalty of the larger camshaft. Note that the use of high-octane unleaded fuel is absolutely essential, as the MoTeC doesn't have a knock sensing function. Interestingly, the standard Gen 3 injectors - running with standard rail pressure - are capable of supplying the necessary amount of fuel.
Finally, Nizpro stresses the amount of development that's gone into their new package. About 40-50 hours have been invested in engine-dyno testing and tuning of the 333 kit - that's in addition to the time spent on the 285 platform...
Results
Take a look at this DynoLog engine dyno graph showing the Nizpro 333 kit (plotted in red) versus the 285 kit (plotted in blue). Note that a factory 225-255kW spec engine was used in both examples.
At low rpm, the 333 kit produces less torque than the 285 - up to around 6 percent less. At 3500 rpm, however, the 333 kit picks up sharply and holds a superior torque plateau throughout the upper mid-range. Peak torque is 408ft-lb at 4950 rpm, compared to the 285 kit's 379ft-lb at 4800 rpm.
In the top-end, the Nizpro camshaft maintains over 90 percent of its available torque right up to redline. Peak power - 333kW - is attained at 6250 rpm, whereas the standard cam'd 285 kit gives peak power at 5850 rpm.
The shape of this torque curve is typical of a 'hot cam' installation - less torque down low, but an increase throughout the top-end. But the trade-off is well balanced - this isn't just a high-rpm revver.
However, due to the changed torque characteristics, Nizpro tell us their 333 kit isn't perfect in a towing application - it is, however, ideal as a performance engine. Idle quality is reputedly very good - though there's a noticeable lope to it - and driveability remains strong.
Fuel consumption had not been quantified at the time of writing, but we're assured that at large throttle openings it's better than the standard engine (which runs very rich). Emissions are also yet to be quantified, but Nizpro are hopeful of meeting ADR standards.
Dollars and Sense...
For AUS$10,000 Nizpro can rouse your factory 225-255kW engine to 333kW, or a factory 300kW engine to around 340kW.
The best value power gain comes when you apply the kit to the base 225kW factory engine - in this instance, your $10k gives around 50 percent more grunt. Installing the kit on a 255kW factory engine gives just over a 30 percent gain, while the factory 300kW picks up only around 15 percent.
Without a supercharger, extracting more power from the factory 300kW engine is never going to be easy...
So is all this good or bad value, you ask.
Well, we've previously covered the installation of a Vortech supercharger and intercooler kit on a 255kW HSV R8 ["Boosting the LS1"]. Running 7 psi, the blower boosted power by 41 percent and the overall cost was just over $14,000.
It's a tough choice.
As outlined in our story on the 285 kit, however, the Nizpro package does have a few advantages. First, the kit delivers sustainable power (because there are no major heat issues to contend with), it's unobtrusive when you pop the bonnet, and it comes with the fantastic MoTeC M800 ECU - the management unit's tuning flexibility could prove invaluable down the track.
One of the biggest downsides is it's more difficult to revert back to standard. Engine smoothness is also affected.
Backing the 333 kit is a 12-month warranty on the MoTeC computer and Nizpro offers a 6-month warranty on their extractors, exhaust and intake. The camshaft and its associated hardware is not covered unless Nizpro are in charge of subsequent servicing - particularly oil change intervals and the oil quality used. Absolutely not covered is the rest of the engine or the driveline.
Wrapping up, the Nizpro 333 upgrade is exceptionally well developed and offers excellent power for the money. In the marketplace, it all boils down to whether you prefer naturally aspirated power or bolting a blower onto the standard engine.
Note - Nizpro are currently looking at recalibrating the factory Holden ECU as an option to the expensive MoTeC M800 add-on. They are also in the midst of developing a free-flow intake manifold. Give them a call for up-to-date details.
Contact:
Nizpro
+61 3 9761 1522
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Nizpro vs HSV?
Kilowatts from HSV are certainly a lot more expensive than they are from Nizpro. Brand new, a basic 225kW SS Commodore is priced at $48,000. It costs an extra $9000 - $19,000 to enjoy the HSV Clubsport's 255kW, and you need a full $95,000 if you want the HSV SV300's 300kWs. How many people can afford that? If your biggest attraction to HSVs is their extra power, keep in mind you need spend 'only' $10k with Nizpro to achieve a massive 333kW... The absolute cheapest way to get yourself into a SV300-beater is to start off with a second-hand 5.7-litre Gen III 1999-2000 VT Gen Executive. Currently these can be bought from $28,000, and - adding 10 grand for the Nizpro 333 kit - you've got an ultimate sleeper for under $40,000. If you're after an excellent all-round package, however, we'd highly recommend a current HSV Clubsport R8 with its optional premium brake upgrade. In standard form, these machines offer excellent handling, braking, practicality, comfort and looks; stir in 333 of Nizpro's kilowatts and you'd have a vehicle to die for. The all-up cost of such a combo equates to around $77,000 - a heck of a lot cheaper than the SV300.
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