O.K. so I already acquired a brand new JCW intake plus a JCW exhaust for my '05 MCS, now I'm looking to buy a set of JCW injectors and my questions in regards to them are the following:
1. Will it affect/harm the engine? It will be a bone-stock MCS with the JCW intake, Alta silicone hose and JCW exhaust.
2. Will the engine start "pinging" so badly that I would have to switch to "colder" plugs?
3. Would the injectors have any "performance" gains?

Please let me know.

Thanks

 

The JCW injectors won't harm the engine, but without retuning the ECU, you're not going to get any performance benefit from them, either.

Basically, your ECU is going to think you still have stock injectors, but the JCW injectors will flow about 15% more fuel than then ECU is expecting, so the air/fuel mixture will be about 15% too rich.

The ECU will detect this rich condition and adjust the long-term fuel trim to compensate. The trim can compensate for up to about 30% extra fuel, so the ECU will have no problems adapting to the JCW injectors. In the end, your engine will be receiving just as much fuel as it was before - the JCW injectors just won't have to be "on" for as long in order to deliver the same amount of fuel as the stock injectors.

You won't need to change your spark plugs.

 

Ditto the above. You might want to spend your mod money somewhere else until you are ready for a pulley and a tune, then the injectors are needed.

 

Yep......go for a 15% pulley and custom tune with the injectors.