some help with tuning
 

hey all,

I want to buy an SCT Xcal. Aparently it can hold four tunes. But I don't fully understand what a "tune" is.

Is a "tune" an INDIVIDUAL parameter, such as changing air/fuel ratio? Or is a "tune" a SET of parameters such as "change fuel/air, adjust rev limit, and change timing"?

I have an 05 v6. Soon will have dual exhaust, new rear end gears, CAI, and an underdrive pulley. Can anyone suggest the best tunes after these have been installed? (I do want my spedometer to be accurate and I DONT want to kill my engine.) I was thinking changing the timing, air/fuel, rev limit, and change spedometer to recognize the new gears and stuff.

Feedback, anyone?

no diff setups....
like race gas only
or
gas saver
or
nitrous on

you would dl the program and go...

if you get an xcal2, it will come with at least 1 custom tune put together for your vehicle. your dealer creates the tune based upon there research and experience as to what settings work best, ie offer most performance. of course, with mail order tunes, they can't be as aggressive so there is much more liability, since they only go on a list of mods you provide. dyno tuning will give the best results, as they can dial it in perfectly, but will cost you more.

as far as what a tune is, it is going to be basically what controls the computer system in the car. there may be subtle changes from stock or drastic changes, depending on application. A/f, timing, rev limit, speed limit, things like that are pretty basic and you would have the ability to change those on your own from what the dealer sets them at. behind the scenes, the dealer can change fuel trims, idle decay and of course many others, just various things like that which require extensive knowledge to adjust safely. you could get the pro racer's package if you are willing to learn about the computer system and such and tune it out on your own, although another cost.

if buy one now, even though gains won't be as big considering current mods, if you continue to build it in the future it will be more and more crucial for a good tune, and then you will already have the hardware. a tuner will simply just create a new tune for you. i say get it now, and take advantage of the gains. Then like I say, you will be ready down the road.

Scott

thanks for the reply---very helpful.

Now, if I get an Xcal (just Xcal, not Xcal2), and then I get some more work done to my car over the years, how do I get the Xcal to get updated tunes? Do I send it back to the company to get them to erase an old tune and program in an updated one? Or do I have to go to a dyno center?

You can go to a Dyno and have them do the tuning on the dyno, or, there is a port on the back of the X-Cal that you can use to plug up to your PC and transfer tunes from an e-mail to your tuner.

All depends on when in your process of upgrading you decide you need a tune :)