IMPROVED NITROUS OXIDE INJECTION
All nitrous companies continue to improve their conventional nitrous oxide delivery systems. Obviously, the more fuel and nitrous oxide you can feed the engine the more power it will make. There is at least one new system being produced that hasn't found its way onto a nitrous Pro Mod engine yet. One of the last projects developed by the old NOS company before it joined the Holley "family" was an annular discharge, nitrous plate system (photo above).

Tests of this plate on engine builder Pat Musi's dyno have claimed results of 500-hp from a single plate with a controller. According to a tech at NOS, the annular flow plate requires less nitrous to make power than the standard plate system. This annular flow plate mixes the fuel and nitrous more uniformly, resulting in fewer "hot spots" in the combustion chamber and less detonation. It hasn't been proven yet, but it is certainly a tool available to the nitrous racers looking for more power.

Programmable electronic fuel injection is another fuel delivery system that can help prevent a too lean condition in the combustion chamber. EFI offers engine tuners the added advantage of being able give each individual cylinder what it needs in the way of fuel for optimum efficiency. Currently only Harold Martin (top photo) is using EFI on an IHRA Pro Modified engine although several other teams have been said to be considering the move.

BETTER AND MORE POWERFUL IGNITIONS
Detonation is a very big, very expensive problem in nitrous oxide injection engines and a limiting factor for how much power a tuner can make. A variety of factors can produce detonation, including too much timing, too much compression or a too-lean fuel mixture. Better fuel delivery has already been discussed as one of the cures for detonation, but there are some other possible solutions as well.

One is to use a programmable ignition system. Several ignition companies offer programmable ignitions, but the one that seems to be favored currently is the MSD Digital-7 ignition. This ignition system allows the tuner to advance or retard individual cylinder timing when and as much as needed on each shift. He can also do the same with total timing. Currently only Mitch Stott, who with his brother Quain have recorded the lowest elapsed time of the year at 6.324, is using that type of ignition full time.

Another ignition option available to nitrous racers is the MSD-44 amp magneto. Conventional CD ignitions are generally accepted as being fine for all applications excluding blown alky and nitro. There are those engine builders who think an engine being fed a big dose of nitrous has an environment in the combustion chamber more similar to a nitromethane motor than a gasoline motor. In other words, a nitrous motor needs the biggest, fattest spark available to keep burning fuel and not get blown out or drowned by fuel; more than any CD style ignition can supply.

Technicians at MSD say that their 44-amp magnetos supply more current than their CD-style ignitions. One racer testing the MSD magneto is Tommy Grey who runs the "Undertaker" '53 Corvette. It is believed he is trying a mag for two reasons:

1. If he can find an ignition that will fire under bigger loads of nitrous and whatever gasoline he is using, the engine will make more power and
2. A hotter, fatter spark will make for more complete combustion, which will help cut down on detonation.

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