Accepted Answer

The 4.10 is an excellent upgrade with instantly noticeable results. You should be very pleased with it. make sure that you have the speedometer reprogrammed for the new gears or it will be off.

The cold air system is a good start as well. You will probably not motice quite the improvement that the gears gave you but you may notice an improvement. The most noticeable improvement with the air intake is the 2-3 mpg increase with normal driving that I saw after installing mine. The Callaway "honker" is my favorite for the air intake.

As far as the F55 being programmed out, I am sure it can be done but I am not sure what equipment would be needed. I would contact your local dyno tuning shop that does the GM cars in your area. They have the equipment to write custom programs and the programmers usually know what they are doing. The dealer does not have the ability to program it out. The only issue that would come up from it being disabled is a message on the message center and the traction control would not work but that's it.
Most guy just run them this way but the message can get annoying.

As far as other things to consider for engine upgrades:

• Headers
  
• Catback (I like the corsa personally but this is a very personal thing)
  
• Dyno tuning (the Ls1 really responds well to dyno tuning)
• Heads and Cam (these should be done together) +100hp
• Intake manifold and throttle body ($1000+ with a gain of about 20hp) I recommend the Fast 92mm if you choose this one but the return is not that much considering the investment.

Please let me know if there is anything else I can help you with

Thanks,

Todd

If you feel that I have answered your question, Please press "accept" and any amount of bonus is appreciated and positive feedback is appreciated. Thank you for choosing justanswer.com

Expert:	Todd
Pos. Feedback:	100.0 %
Accepts:
Answered:	8/26/2009

ASE Certified Technician

ASE Master Technician, 10 years experience with Volvo, Mercedes, BMW, VW/Audi , asian and domestic