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We chose the Nitrous Oxide Systems (NOS) Super Power Shot system because it appeared to be the best deal for the money. |
The advantage of the Super Power Shot system is these jets. By changing the jets located just upstream of the plate, you can vary the amount of nitrous and fuel delivered to the engine. |
The solenoids used with the Super Power Shot system are larger than the least expensive Sniper kit and can therefore flow more nitrous and fuel for more horsepower. |
Moore chose to mount the bottle in the trunk where it can easily be hidden if necessary. This is actually a slightly larger 15-pound NOS bottle that we wanted to test-fit. |
The NOS undercarb plate is only 1/2-inch tall, which allows us to mount the plate without hood interference. Moore built a new mild-steel hard line between the Carter fuel pump and the carb. |
Most nitrous systems employ a main power arming switch along with a micro-switch (circled) located on the carburetor that completes the electrical circuit to both solenoids. |
NOS suggests retarding timing based on the amount of nitrous added to the engine. |
We chose a pair of Mickey Thompson 26x8.5x15-inch ET Street tires mounted on a pair of borrowed Center Line wheels to help us hook up all that power. |
Moore selected a B&M TransKit for the trans rebuild. The B&M systems supplies all the friction materials, bands, gaskets, and seals to completely rebuild the TH700-R4. |
While these Bosch plugs look identical, the one on the left is two steps colder. |
When installing a nitrous bottle in a hatchback vehicle, you must use a blow-down tube and pressure relief valve to vent nitrous to the outside of the car. |
This is an expanded-view illustration of how a basic plate nitrous system is laid out. |
Last time, we left off with the Camaro running 15.39 at 87.28 mph after we added ported World Products S/R Torquer heads and an emissions-legal Crane hydraulic roller camshaft. We improved the e.t. over 0.40 second, but frankly we were disappointed that the Camaro didnt run quicker. It was at this point that we decided to get serious.
Whenever bang for the buck comes up, nitrous is always at the top of the list. Its tough to improve upon even a basic nitrous system that will add 100 to 175 hp for around $400. Since we had just rebuilt the 305, we felt confident that the engine could handle the extra power, and we went shopping for a nitrous system.
Companies such as 10,000 RPM, Edelbrock, NitrousWorks, Nitrous Express, Nitrous Oxide Systems, and many other offer a wide selection of nitrous systems based on what you need. We went looking for an entry-level system and found several that would suit our needs. The least expensive systems dont offer the advantage of changing jets, which is a tuning option we wanted. We decided on the Nitrous Oxide Systems Super PowerShot system, which can deliver a range of power increases from 100 hp to as much as 175 hp.
The system is designed around the classic nitrous plate where a ½-inch spray bar plate is installed underneath the carburetor. One spray bar connects to the fuel delivery side while the other delivers nitrous. The solenoids are electrically controlled and open when electrical current is applied to them. The system uses both an arming switch and throttle-mounted micro-switch to trigger the nitrous only at wide open throttle (WOT).
Moore mounted the bottle in the trunk area of the Camaro and installed a nitrous dump tube that directs any overflow from the pressure relief valve outside the car. The relief valve is used on all nitrous bottles to vent any pressure exceeding the safety rating for the bottle. Its important to always treat a nitrous bottle with a great deal of respect since even normal bottle pressure is around 900 psi.
Bolting the system on the car is relatively simple. The solenoids mount adjacent to the plate and are wired through both the throttle-mounted micro-switch and the main arming switch. The biggest job involved plumbing an entirely new fuel delivery line from the Carter pump up to the carburetor.
Even with a simple 100 to 175hp system, you must still have a good fuel delivery system as well as a solid ignition system. Moore changed to a Carter performance fuel pump to ensure adequate fuel delivery and had to re-do the fuel lines in the process. The pump has enough capacity and pressure to supply both the engine and the nitrous. Just to be sure, we borrowed an Auto Meter fuel pressure gauge and tested the fuel delivery system at speed with the nitrous line disconnected to ensure that we had sufficient fuel pressure under load. NOS recommends a minimum of 4.5 psi of fuel pressure under load and the Carter mechanical pump delivered over 5 psi for the entire run.
With everything hooked up and working properly, we took the Camaro back to LACR for another assault on the quarter-mile. Again, the weather was oppressively hot with temps in the mid 90s and a density altitude of 6,200 feet.
We started out with the mildest jetting in the nitrous plate to see how well the car reacted to a 100hp jump in power. Even a mild nitrous system will deliver the equivalent of a big kick in the pants because of the huge torque gain that nitrous delivers. The stock ignition couldnt fire the old plugs, so the best we could do was a 14.85/93.33.
The previous test had come with stock plugs and timing. We also changed to a two-step colder set of Bosch plugs. While we would normally retard the timing, we felt that the electronic spark control (ESC) would handle any detonation, and we had a load of 92-octane fuel plus some octane boost in the tank. We lowered the tire pressure slightly in the M/T ET Street sticky tires and pulled to the line after a short burnout. It was obvious the moment Moore hit the throttle that the Camaro was heading for a good pass.
We suffered from a slight amount of tire spin when the nitrous first hit off the line, but the Camaro still responded with an impressive 13.82 at 100.23 mph effort that turned out to be the best pass of the day.
This computes out to over 3½-seconds quicker and well over 21 mph faster, all for a total expenditure of slightly more than $5,200 including the cost of the car. We also accomplished this with all emission-legal parts, a 305ci engine, and iron heads. Frankly, were not completely thrilled with the Camaros performance, but we did come in just slightly over our original budget of $5,000.
Considering that weve spent very little money on it, having a Camaro that is solidly in the 13s, is fun to drive, and gets over 20 mpg on the freeway isnt bad. Whats holding us back is the displacement-limited 305ci engine and the emissions requirements.
So whats next? Were thinking about building our own 350ci version of the emissions-legal package that GM Performance Parts offers, but thats just one of the several options were investigating.
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