Electrical: Consider the following bulbs............

[Hawklover]

Assume you are holding the following:
a 57 bulb
a 1445 bulb
a 1816 bulb

Are the glass bulbs the same size?

[kurtruk]

The BASES are the same. The overall length is very close. 57 max length is 1.06 inches. 1445 is 15/16 in. 1816 is 1.19 inches. Are you looking for the diameter of the glass part? Each one is different.

Here's more specs:
Voltage:
57 14v
1445 14.4v
1816 13v

Amps:
57 ,24
1445 .135
1816 .33

Watts
57 3.36
1445 1.94
1816 4.29

Candle power
57 2cp
1445 7? cp
1816 3cp

If you need to know the diameter of the glass I will need to do more research.

All info courtesy of Internet Archive Wayback Machine Don's Bulbs

[Hawklover]

I asked because of the change of specific bulbs for the Avanti. The clock and the vac gauge changed from 1445 to a 57, other places to 1816. The bottom line is that I want to replace the bulbs from 57s in the clock and vac gauge with the following "superbrightled" varient: BA9s-RHP5, and the 1445 which are in the heater header, and are in the console with the same number LEDs ....the light in those areas is a bit dull to my "old' eyes. I just hope the led area fits in the space of both the 1445 and 57.

[RadioRoy]

You might want to look at some pictures. The LED "replacements" that I have seen are mostly larger/longer/shaped differently than the incandescent bulbs they replace.

[Hawklover]

You might want to look at some pictures. The LED "replacements" that I have seen are mostly larger/longer/shaped differently than the incandescent bulbs they replace.

Thank you, I will.

[bezhawk]

The 5 smd bulbs from Superbright LEDs fit in every space in Avantis. You want RED ones for everything except the turn signals then of course order two green ones. I have done a dozen cars converted, and there is no comparison. If they are too bright for you, I use a PWM (pulse width modulator) controller to dim them with and do away with the resistor. Lowering the input voltage to an LED does NOT dim them much. As a solid-state device, once they reach the forward bias voltage (1.414 volts) they are ON.
You need two for the overhead switch panel, two for the console panel, one for the temp, and ammeter gauge, two for the three for the speedometer (including the high beam indicator, and one for the gas, oil pressure. One for the vacuum gauge, and one for the clock. The only thing they won't fit is the shifter light, and the ash tray cigar lighter, and the AC status light.

[Hawklover]

The 5 smd bulbs from Superbright LEDs fit in every space in Avantis. You want RED ones for everything except the turn signals then of course order two green ones. I have done a dozen cars converted, and there is no comparison. If they are too bright for you, I use a PWM (pulse width modulator) controller to dim them with and do away with the resistor. Lowering the input voltage to an LED does NOT dim them much. As a solid-state device, once they reach the forward bias voltage (1.414 volts) they are ON.
You need two for the overhead switch panel, two for the console panel, one for the temp, and ammeter gauge, two for the three for the speedometer (including the high beam indicator, and one for the gas, oil pressure. One for the vacuum gauge, and one for the clock. The only thing they won't fit is the shifter light, and the ash tray cigar lighter, and the AC status light.

Brad thank you so much for your post! First I did replace the two bulbs with those LEDs in the two light boxes, FANTASTIC, those suckers more than compensated for the 50 plus years of dust accumulation inside those boxes! I do not like the light being emitted from the clock and the vac gauge, so those 1895 reds will be replaced, the tack and the speedo will remain with the 57reds because to my eyes they are fine, I will replace the those inside the overhead sw panel, and the two inside the console panel, both of these areas were again to my eyes very dim. Also I see no need for the lights to ever be on dim mode, and have always had them on bright mode, and that means since late 1966 when I purchased the car. I do have to check ground in two places, the clock, and the trunk light. Fortunately I have a new HG switch for the trunk, just in case. The car is 4speed so no need for a shifter light.

[Hawklover]

An update:
First the # 90 bulb in the trunk. The LED replacement almost fits but the base is just a hair to long. So back in went the 90.
The 5 tier LED red bulbs will fit in most all places............except the overhead header panel. Too long and hit the inside of the crash pad. So back in went the old standard red bulbs. I am happy the dash board LEDS did fit.

[Hawklover]

The 5 smd bulbs from Superbright LEDs fit in every space in Avantis. You want RED ones for everything except the turn signals then of course order two green ones. I have done a dozen cars converted, and there is no comparison. If they are too bright for you, I use a PWM (pulse width modulator) controller to dim them with and do away with the resistor. Lowering the input voltage to an LED does NOT dim them much. As a solid-state device, once they reach the forward bias voltage (1.414 volts) they are ON.
You need two for the overhead switch panel, two for the console panel, one for the temp, and ammeter gauge, two for the three for the speedometer (including the high beam indicator, and one for the gas, oil pressure. One for the vacuum gauge, and one for the clock. The only thing they won't fit is the shifter light, and the ash tray cigar lighter, and the AC status light.

Brad those bulbs will not fit the overhead heater panel, they are a bit too long and hit the pad..........had to continue to use the 1445 bulbs, but re-wired them so each of the bulbs received a full 12Volts. As I discovered those specific bulbs are wired in series.

[bezhawk]

Unless they changed dimensions, I have never had any trouble installing them. You do have the correct plastic sockets holding them don't you?

[Hawklover]

Unless they changed dimensions, I have never had any trouble installing them. You do have the correct plastic sockets holding them don't you?

Yes I have the correct sockets, the leds I used were the 5 tower type, same I used in all the instruments on the dash.