so I just put in my PIAA blue LED bulbs in my gauges and to my dissapointment they didn't come out as bright as I expected. Could there be a reason why this is?? Or maybe I need a different kind of bulb, but isn't PIAA top of the line anyway???

 

ehh, the blue coating probably sucked away a lot of the light output. i tried blue bulbs before, and the output sucked. then i got some red ones from cardomain and pretty happy since.

 

you know whats weird? the coating is clear. what bulbs did you use?

 

for hight output leds, I don't think the color is impregnated into the casing itself, i.e. "coating", but rather a transparent substrate being put onto the "cup" portion of the LED.
Also, LEDs have a very narrow angle of light compared to incandecent bulb, even the wider angle LEDs, the way they countered this is to make a big frikkin bulb out of an assembly of led with one or several facing foward, and a ring around the base of the forward facing LED, but this won't do for your application since space limitation will prevent you from doing so.

Also, when you look into the light bulb holes in the back of your gauges, do you see clear plastic that SURROUNDS the bulbs? These plastic pieces works to distribute the light efficiently to the bulb-less area of the gauges much like how fiber optic lines works. With this and the narrow angle of light that the LED produces, which is faced FORWARD, you can see why the leds will not light up your dash as you hope it would.

To summerize things up, I think you're better off with incandecent bulbs, they do last, and replacing is not too much of a pain, (I pulled my gauge cluster apart for fun so many times)

you do have a choice of:

clear(regular)
red
purple (who would want these in their dash????)
green (makes the max gauges looks like cheap economy cars)
amber(my personal favorite, makes the thing looks like a BMW, plus it bright as hell as they were designed for turn signals)
and finally...
BLUE

hope this had help

 

ah crap, didn't see that he wrote LED in his post thought he used regular bulbs.