tuning in car: Grassroots Motorsports forum: Grassroots Motorsports Magazine

Subscribe get a full year for only $23.95 Sample Free Test Drive—no strings attached

Oct. 23, 2011 10:59 a.m. Rustspecs13 Reader

So I'm about to start street tuning my car. My battery does last a good 2-3-4 hours on power saver mode, but the screen is very dark and hard to see unless its night time. And on full power/even a balanced power program, it still eats up batter in just over an hour. Mainly only a problem if the battery isnt 100% Either way its just 10x easier to have constant power so:

Should I be normal, and get a 12v > 120v power supply, then use my normal 120v wall charger for the laptop?

Or is there a GRM solution that doesn't change voltage ranges and phases twice for almost no reason?

~Alex
Oct. 23, 2011 11:43 a.m. SkinnyG HalfDork

I bought an inverter to run 120V in the car to run TunerStudio on my old old laptop (battery lasts 7 minutes, but laptop has a serial port in it). You'll probably need at least 300W to feed the laptop. This has worked super awesome for me.
Oct. 23, 2011 12:09 p.m. pres589 Dork

Power output should be labeled on the power brick for the laptop, and then figure on, what, 80% efficiency? Switching supplies are fairly efficient. My Apple laptops use 85 watt or smaller power bricks, I think my old Compaq (with both serial and USB ports so I keep it around for projects that so far never come along) was 50 watts or so. You shouldn't need much for an inverter to drive a laptop.
Oct. 23, 2011 12:57 p.m. peter Reader

Another vote for inverter. An el-cheapo one from Amazon powered my MacBook Pro just fine when I was putzing with my MegaSquirt...