I have a 03 sedan, current mods are a 5/16 spacer and HFC. I will soon be adding header. After the header install I want to do a reflash.

Here are my questions. Should I do any more mods before the reflash that will really benefit me in performance? Am I missing anything important? All of the research that I have done pretty much states that a CAI or Z tube combo doesnt really add any noticible power (just noise). However I may do a K&N drop in. I know that I may be giving up some power with out adding a cat back exhaust but I don't want my car any louder than it has to be. I have searched a lot and found that the stock air intake and exhaust flow pretty well. I will probaly never go FI BTW.

thanks for your input

 

if you are looking towards TS reflash the only thing associated with your mods will be air fuel ratio... other than that its bumped rev limiter, omitted speed limiter and reprogrammed drive by wire that improves throttle response and opens full at wide open throttle... so to answer your question, if you do not plan on future breather mods it really won’t matter.

You might want to consider dyno with A/F ratio to determine if you even need full flash (adjusting A/F) or just L-Flash (limited flash) addressing everything else I mentioned

 

If you're going with TS, I would do the exhaust & intake before the flash, with the mods you already stated.

If you're going with the new UpRev Osiris, which I am completely sold on, it really doesnt matter; they can update your flash for free once you add more modifications.

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