i saw a shift light and a boost gauge combo on e-bay, but they say the shift light works off of the cigarette lighter in the car. my question is how do they sense the rpm of the engine by the cigarette lighter, or it is a scam.


thanks in advance for your input.

 

a link to the actual item would have been nice.

 

Is this what you're talking about?

http://cgi.ebay.com/ebaymotors/ws/eB...spagename=WD1V

If so, quit scoping ebay for cheap-*** **** and buy decent quality equipment, please. What do you need a shift light for anyway? Are you a frequent road or drag racer?

 

it works, I'm not sure how accurately.

my friend had a gtech and it calculates rpm's through the cig lighter as well...he could never get it calibrated correctly (either that or it just wasn't too accurate), it was about 500rpm's off his actual rpm but the amount that it was off was always consistently about 500rpm's past the actual rpm's he was turning.

anyway yeah, stay away from that retarded cheap ebay ****.

 

Ditto w/ the stay away from ebay idea. I do like the idea of mounting it in the A-pillar tho. I may have to try that...relocating it to a less obvious place (than the dash). I get the signal from the tach itself. It's in the diagnostic box, marked IGN IIRC. It has pills you place to set the shift point as you desire. It's an Autometer btw (only company that makes a stand-alone shift light AFAIK...although Defi was rumored to have one, but this was never confirmed).