Description
The J&S Ultra Safeguard is a unit that uses the signal from your knock sensor to detect detonation. When it hears this specific signal, it will retard your timing maps accordingly until the knock, or ping, is no longer heard. Yes, the stock 3S-GTE ECU has a similar feature in which it listens to the knock signal, and does retard timing when it hears knock. However, the ECU will only react when it hears very severe knock, often times when it is much too late to save the engine. Not only that, however, the stock ECU does not retard the timing maps in a way that is beneficial to performance. Instead, the ECU will retard timing significantly in order to eliminate knock as quickly as possible, and performance suffers drastically. As it takes out so much timing that the exhaust temperatures skyrocket, which is not especially safe for your engine either.
The J&S operates much more efficiently than the stock system, in that it will only retard timing until knock is no longer heard. Timing adjustments are small and are dependent on the count of knock that it hears. It can retard one or two degrees per knock, depending on how you set the system. Therefore, it allows you to make the maximum amount of power your timing maps allow without getting detonation. The J&S has a few different options that you can make use of. You are able to select between a "retard all" and an "individual retard" mode. In the "retard all" mode, the J&S will generally apply the ignition retard to all cylinders when it hears knock. On the individual retard mode, the J&S will remember when it hears detonation. Since it knows how many cylinders your car has (preprogrammed), it will count. Basically, it will go 1, 2, knock, 4, 1, 2, retard, 4. That is, it only retards the ignition timing on the cylinders that are knocking. You are also able to adjust the timing for additional boost. This option is useful for cars that are fitted with an aftermarket turbocharger, upgrading from a normally aspriated engine. The operation of this feature is very similar to that of the MSD BTM. Clearly the J&S is a much more capable unit than the MSD BTM. You can select anywhere from zero to two degrees of retard per additional pound of boost added. Lastly, you can adjust the sensitivity level for properly tuning it to your car. Adjusting the sensitivity is fairly easy. You set it to the point where you know that you have no knock occuring, and while driving, the J&S just barely reatards timing. You can do this by turning down the boost, adding race gas, or simply setting it on your engine that you are confident is not experiencing detonation. An engine that has been running very well without any problems, for a long time, in a specific set up, is a good example.
Installation
The installation of the J&S is fairly straight forward. The diagram included with the system is very descriptive. There are only a few wires that need to be connected. Essentially, the unit requires power and ground, the IGT signal from the ECU, the knock sensor signal from the ECU, the turbo pressure sensor signal (PIM), and the O2 sensor signal for the gauge. Installing the gauge is very easy, since the cables are included. The knock retard part of the gauge has a stereo cable that simply plugs into the main unit. The o2 section has a cable that must be connected to the O2 signal (OX1) and ground.
The following diagram shows how to attach the wires for the install:
Opinion
I love the J&S Safeguard. It is simple to install, and, well, works! It adjusts the timing maps extremely quickly, so that even though it is a reactionary device (needs to hear knock in order to retard timing), it is able to react on the first signs of knock so that there isn't enough time for damage to occur. On individual cylinder mode, the car feels VERY strong throughout the powerband. It is very interesting to watch some cylinders be retarded several degrees while others need no adjustment. I have been running the system for several months now with no problems. One other good use for it is when you are stranded and can not purchase the octane fuel that your car is tuned for. Since I usually run 94 Octane gas, occasionally I am not able to find it when out of town. The difference is amazing. On 91 octane gas the J&S picks up the extra detonation right away and keeps your engine from suffering any damage.
Additionally, I will be installing my Perfect Power SMT-6 and using the J&S to help me street tune the system. With a wide band o2 sensor and the J&S, I should have no trouble tuning the piggyback system to keep my engine knock-free.
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