K
Keith@FP
There are four ways to deliver more fuel, one of which is a poor option.
- higher pressure, stock injectors. This is easy, inexpensive and works well up to about 8 psi if the extra pressure is tied to boost level. For those looking for an affordable kit, it's the preferred method. It can also be CARB approved. OBD-II is untouched.
- stock injectors with auxiliaries. This involves a bit of extra plumbing, but can also be CARB approved. The extra injectors are controlled by a separate device such as the Link piggyback, and this means they only add fuel when fuel is needed. Otherwise, you're basically driving a stock car as long as you stay out of boost. Some of the controllers also can do timing changes, such as the Link. (I know the Links well, thus my use of it for examples. There are other options). This is what we do for the 1999+ Miatas. The wiring can be quite simple. OBD-II is untouched.
-bigger injectors in place of stock, stock ECU. Some people think this is a good alternative because it's cheap. However, it means the car runs rich all the time. Basically, the car gets set up to run under full boost ONLY - not good. This is a poor solution. OBD-II will probably start throwing codes.
- bigger injectors in place of stock, different ECU. This is our choice for the top-end 1990-97 Miata kits. The programmable ECU can either run just fuel and timing or control the entire car. It's the best choice, but it's also quite expensive. It's impossible to get CARB approval for it. Wiring can be complex, depending on how the setup is tailored. OBD-II often gets tossed right out the window.
We're concentrating on lower-boost systems right now as we learn the capabilities of the Proteg platform.
Keith
- higher pressure, stock injectors. This is easy, inexpensive and works well up to about 8 psi if the extra pressure is tied to boost level. For those looking for an affordable kit, it's the preferred method. It can also be CARB approved. OBD-II is untouched.
- stock injectors with auxiliaries. This involves a bit of extra plumbing, but can also be CARB approved. The extra injectors are controlled by a separate device such as the Link piggyback, and this means they only add fuel when fuel is needed. Otherwise, you're basically driving a stock car as long as you stay out of boost. Some of the controllers also can do timing changes, such as the Link. (I know the Links well, thus my use of it for examples. There are other options). This is what we do for the 1999+ Miatas. The wiring can be quite simple. OBD-II is untouched.
-bigger injectors in place of stock, stock ECU. Some people think this is a good alternative because it's cheap. However, it means the car runs rich all the time. Basically, the car gets set up to run under full boost ONLY - not good. This is a poor solution. OBD-II will probably start throwing codes.
- bigger injectors in place of stock, different ECU. This is our choice for the top-end 1990-97 Miata kits. The programmable ECU can either run just fuel and timing or control the entire car. It's the best choice, but it's also quite expensive. It's impossible to get CARB approval for it. Wiring can be complex, depending on how the setup is tailored. OBD-II often gets tossed right out the window.
We're concentrating on lower-boost systems right now as we learn the capabilities of the Proteg platform.
Keith
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