Power Pages: 1991 Nissan 300ZX

Owner: Katshiji Yakushige
Dynamometer model: DynaPack

DYNO1: Baseline
Baseline air temp @ 65.6 Degrees Fahrenheit Peak HP 223.4
Peak TQ 233.7

Baseline Horsepower: 312.0
Baseline Torque: 273.6 lb-ft

Pros:
Since the beginning of Import Tuner we have never done a Power Page on a Nissan 300ZX. After five years we have finally located a 300ZX with lower-than-normal mileage and in stock condition. From the factory the car stepped ahead of the competition with its 300 horsepower VG30 engine. At the time of the car's arrival, aftermarket parts were a mere handful. Flash to today and the 300ZX can pack a heavy arsenal. This is exactly what we are going to find out.

Cons:
The engine bay is pretty packed so installing stuff isn't exactly the easiest process. The Z is still a strong force to be reckoned with as it's following is just as big as another big hitter, the Toyota Supra.

Dyno Notes:
After a quick tune up the car ran flawlessly on the dyno. One thing you have to remember is this car is 13 years old.

Install time: 1 - 1.5 hour

DYNO 2: APEXi GT Spec Muffler

Air temp @ 66.7 Degrees Fahrenheit
Temperature difference from previous run 1.1 Degrees Fahrenheit

Peak HP 229.2
Peak TQ 245.2

2000 to 3500 HP Range: 0 to 2
3500 to 5500 HP Range: 0 to 2
5500 to redline HP Range: 3 to 5

2000 to 3500 TQ Range: 5
3500 to 5500 TQ Range: 2 to 10
5500 to redline TQ Range: 2 to 5

Peak Horsepower: 229.2
Peak Torque: 245.2

Pros:
Cons:
idering the car has been on the road for 13 years, it was impressive that there wasn't any rust, making the install very easy. The mufflers themselves are pretty big but obviously that didn't stop the car from making horsepower. Piping starts out 70mm aluminized steel while the tips come in 75mm stainless.

Cons:
None

Parts include:
B pipes, two mufflers, eight nuts and bolts.

Tools required for install:
12-, 14- and 17mm sockets and ratchet.

Dyno Notes:
With the catalytic still in place the exhaust was very quiet until you get on the throttle. Even so it wasn't very loud at full throttle.

Install time:: 1 - 1.5 hour

DYNO 3: APEXi Air Filter
Air temp @ 65.2 Degrees Fahrenheit
Temperature difference from previous run -1.5 Degrees Fahrenheit

Peak HP 242.3
Peak TQ 253.7

2000 to 3500 HP Range: 2 to 4
3500 to 5500 HP Range: 6 to 8
5500 to redline HP Range: 10 to 14

2000 to 3500 TQ Range: 4 to 8
3500 to 5500 TQ Range: 8 to 10
5500 to redline TQ Range: 10 to 14

Peak Horsepower: 242.3
Peak Torque: 253.7

Pros:
The access panel on the front of the car makes the install very easy. Since the car is a twin turbo, the A'PEXi adapter allows the two intake pipes to merges the two turbos to one filter.

Cons:
With the filter installed, the A/F went from below 11.5 at 4200 rpm to a higher 12.3 at the same rpm level. This is still pretty safe but for the boost controller install we are definitely going to need some type of fuel computer.

Parts include:
A'PEXi filter, filter adapter, necessary nuts and bolts for the filter and adapter brackets.

Tools required for install:
10mm socket, ratchet, 10mm wrench and Philips screwdriver.

Dyno Notes:
A lot of power but also a higher air fuel ratio than what we want.

Install time:: 45 minutues

DYNO 4: ACT Clutch
Air temp @ 65.0Degrees Fahrenheit
Temperature difference from previous run -.2 Degrees Fahrenheit

Peak HP 242.3
Peak TQ 253.7

2000 to 3500 HP Range: N/A
3500 to 5500 HP Range: N/A
5500 to redline HP Range: N/A

2000 to 3500 TQ Range: N/A
3500 to 5500 TQ Range: N/A
5500 to redline TQ Range: N/A

Peak Horsepower: 242.3
Peak Torque: 253.7

Pros:
The disc is actually a stronger 350Z unit. The pressure plate is ACT spec heat treated to give the spring much more strength and is Sfi certified. Clutch disc is their street unit which is also Sfi certified. The pedal pressure is just a little stiffer than factory. According to ACT, it is 63-percent over stock. The ACT unit is a complete install kit considering it comes with a release bearing, flywheel bushing and even a clutch alignment tool. Talk about saving you a couple of trips to the auto parts store. All it lacks is a resurfaced flywheel and gear oil.

Cons:
Since the ACT clutch is designed to withstand high horsepower and not make more horsepower, there are no before and after power differences. That doesn't change the fact that our car needed the clutch if we are to continue on with a part II for the car.

Cons:
Our original third installment was to be a boost controller but when we tried it on the dyno we ended up smoking the clutch. Since the clutch slippage didn't occur until we tried installing the boost controller our previous runs are still accurate. Since then we removed the boost controller and are going to install it in the next part. The third part now became the ACT clutch. The main thing that the ACT clutch ensured us was that we will not have the problem slippage issue for our next installment.

Parts included:
Clutch disc, pressure plate, release bearing, bushing, clutch alignment tool.

Tools required for install
Think about it... this is a clutch job so it takes a lot of tools. You are best off paying someone to install it.

Install time:: Full day because we had to wait for the flywheel to get resurfaced

Conclusion
What we though was going to be a walk in the park installing an air filter, muffler and boost controller ended up being a catastrophe. The new game plan started with and air filter and exhaust then moving straight to our Power Page project hero, ACT. Lucky for us ACT has plenty of their 300ZX clutches in stock. Thanks Dirk.