I am looking into getting the SCT Xcal tuner, but I really know nothing about cars. I noticed that when it is purchased, the buyer is required to send information about the car (mods and stuff) and describe the tune he or she wants. I however, don't know what tune I want (because I know nothing about how they work and what they control). I know I want my car to go faster, and that's it (without blowing up my engine).

Why would someone want more than one tune? What options are out there? I mean, is it possible to get something like Tune #1 = 87 oct gas saver and Tune # 2= 93 gas guzzling power? If so, can they be switched between on the fly?

Also, if it is possible to have one tune for economy and one for speed with different octanes, what happens if your tank is half full with 87 and half with 93?

thanks

 

1 - Great question...everyone has to start somewhere.

2 - Multiple tunes can be used for many, many things. Listed below are just some standard options. It is up to the tuner and you how you want to package them together into different tunes.

a - Raising or deleting the rev limiter.

b - Changing the speed limiter to either make it go away or to create say a 75 mph max for those pesky teenage drivers in the house. (that's right. You could have a tune for the wife and kids if you want or even make a valet tune).

c - Changing timing. Timing can be advanced for an n/a car to increase hp, but requires high octane. Or, timing can be retarded for nitrous or turbo applications.

d - Changing air/fuel ratio. Increasing the a/f makes more power, but you can't increase it to far, or you will ruin the motor.

e - Two step rev limiter for drag racing.

f - Shutting off the traction control.

g - Calibrating speedo for different sized tires and rims or for gear swaps.

This was just a short list.

You might want to get two tunes. One as an 87 octane tune and the other as a performance oriented 93 octane tune. The tunes can not be switch on the fly unless you buy a chip instead of a tuner and it has to be the style that allows this (I have one for example)

If you have half a tank of 87 and half of 93, you need to run on the 87 tune untill the tank can be filled with 93 in most cases. Running on too low of octane for a tune designed to run on high octane will cause detonation (ping or knock).

 

thanks very much for helping me out! Your reply has generated a few more questions for me...

So a "tune" is defined as a program of certain parameters to adjust, right? Like if I asked the company to make me a tune for high performance, they would incorporate ALL the things you talked about (rev limit, gear ratio/spedometer stuff, etc.) all into one tune?

If so, how many parameters will the company let you have for the tuning fee (I think mustangtuning.com is 25 bucks/tune). As many as the tuner will control?

And why would anyone want more than 2-3 tunes, then? One for economy, one for performance, and perhaps one for valet, but why any more?

thanks again!

 

actually,

now that I read it again, it appears that one "tune" is defined as only ONE parameter. Is that the way it is?

If so, how do I know which parameters to get for a v6 with certain modifications (CAI, 3.73s, dual exhaust, underdrive pulley)? Will the company help me out, or should I just keep asking people in these forums?