ptatohed’s 1999 Supercharged 4thgen Nissan Maxima Quest to 300HP

Last Updated: 08/03/2022 @ 07:27 am

Credit: ptatohed

I went to the “Dyno Day” at Dyno Extreme on Sunday, 03-02-08 in Stanton CA (near Knott’s Berry Farm in Buena Park) with James / The Wizard. Well, I got my highest horsepower to date! 322.76 HP and 307.82 TQ.

Last year I was around 240. So, with an 80+ HP increase, I’m quite stoked, to say the least. A HUGE thanks goes out to Jimbo “The Wizard” Ozouf for helping me crank out 3 pretty big mods in just a week before the dyno.

Total (power) mods and variables are as follows:

• Un-tuned
• Unless I say otherwise below, I have all OEM parts and the “stock” parts that come with the Stillen SC kit (yes this means: stock injectors, stock MAF, standard Vortech FMU with 8:1 disc, Bosch bypass valve, stock fuel pump, etc.)
• One-step colder NGK platinum plugs gapped to 0.037”
• 91 Octane gas
• 13.7 lb 17” rims
• 12.5 lb 12.2” rotors (stock are 15lb ea.)
• Cattman cat-back
• LSS test pipe (just for dyno and track days)
• Warpspeed Fed Spec aluminum Y-Pipe
• Fed Spec. left bank manifold (from Fanaticrock – thanks man!)
  (I did a CA spec –> Fed Spec left exhaust bank manifold conversion which eliminated the huge left bank pre-cat. I installed a Cattman O2 simulator for the two downstream O2 sensors)
  Vortech V2 supercharger, freshly re-built
• 2.87” Vortech SC pulley (see boost/PSI information below)
• Custom intake piping
• A 5”d x 8”l PWR water to air aftercooler (barrel design) with a Bosch water pump, a Jackson Racing front-mount heat exchanger, and a Vortech ice chest/water reservoir.
• Thermal insulation to protect the underside of the intake tubing from the exhaust manifold/engine heat.
• 4th gen. Variable Intake set at 5200 RPMs (installed by The Wizard, the VI master)
• Freshly rebuilt I30t VLSD automatic transmission (with Hayden #403 cooler)
• Perma-Cool oil cooler (not sure if that results in a power increase or not, but, just in case)
• I think that’s it. I hope I am not forgetting anything.
• Oh, and my I30 fuzzy A, B and C pillars (good for at least 10 HP )

I have a bad memory but I think the mods that are new this time (322HP) from last time (240HP) are: one-step colder plugs, lighter rotors, Cattman catback, Fed. Spec. conversion, re-built blower (which fixed a chipped impeller blade and inlet oil leak), a few more PSI, larger PWR AC which replaced a smaller JR AC (see explanation below), 4th gen. VI, VLSD tranny with cooler, oil cooler. But I did have my fuzzy pillars last time (otherwise I would have dynoed at 230)!

As far as the boost / PSI level… Well, on the dyno I made maximum boost of 10PSI. However, I always hit 12PSI max on the street. The dyno owner/operator told me this was normal and it’s because the dyno has less of a load than the street. Huh?

I recently replaced my small 3”d x 11”l Jackson Racing (JR) water to air aftercooler (AC) with the PWR AC mentioned above. The PWR is supposed to be more efficient in cooling and result in less boost loss. I now lose 1PSI across the PWR AC where before I lost 2PSI across the JR AC. I also have a dual intake temperature gauge by Autometer. I have one probe upstream of the AC and one downstream. With my JR I would see about a 10 degree difference during idling/cruising and a max delta of 40^ during a full boost run. With the PWR I know see a 15-20^ delta when cruising and a 60^ delta during a full boost run. During the dyno, I added ice to the ice reservoir and saw a max delta of 85^!

Dyno Extreme didn’t hand out dyno graphs that day. So, excuse me for the digital camera photo of my dyno. The owner should be sending out the run files via e-mail shortly so I will post up the dyno when I get it. Also, these are the uncorrected numbers.

I’m really stoked. Two of my dreams were achieved at once: 1.) Break 300HP and 2.) Get a single-digit weight to horsepower ratio (~2900 lb / 322 HP = 9.00 LB/HP!!).