View Full Version : a few more questions about my 99 cobra

06-29-2006, 04:09 AM
Hey Guys... I have a few more questions for you!
1st off I want to know if my 99 cobra's fuel pump can handle the 03 cobra injectors "39lb"

2nd I was wondering if the lower intake from the 03 cobra would boost my hp or maybe it will not work at all or make my engine blow! thanks

06-29-2006, 06:55 AM
I am sure that the injector would fit and probably operate but since the MAF is not calibrated for use of the higher flow injectors you would run into problems with the Air/fuel mixture. The only time you should change injectors is when you are getting the car tuned (my means of software ajdustments and reprogramming the car's computer) It would be more cost effective to have your car tunned than to just change the injectors. If you are planning to install a supercharger or turbo system on the car than you will more than likely need to change the fuel injectors, must have a tune done, and probably need to upgrade alot more so that you can maintain a safe air/fuel ratio.

As for the lower plenum on the 03/04, the runners are extremely short and would not provide the proper air flow rate into the intake valves if the car is to remain naturally aspirated (lacking forced induction). The FR500 intake plenum would probably be a better choice for a non forced induction motor since it offers a variable geometry runners. The only reason to use an 03 lower plenum is if you have a positive displacement supercharger attached to it. There may be some other intake plenums on the market for the 4.6L motor that may offer better low end torque and not hinder the high end performance and may cost as much as a supercharger.