Super Mario Kart was released in 1992 and has a simple hud. As the game is made in 16 bit style it is only fitting that the hud be in the same style. It is very simple with only a few elements: Map, Timer, Coins and Carts. The starting HUD in this also fits the style.
Mario Kart 64 was released in 1996 and has a more improved HUD but keeps it simple and has a little bit more of info on the screen, e.g players in the race and the time has been changed. At the same time the map has been made more simple.
Mario Kart: Super Circuit was released in 2001 and has kept the same graphics but changed the font of most of the text to make it smaller, but still has virtually the same design. They also removed the player places on the side as this probably took up way to much space on the HUD. Also they kept the items box in the centre as it is easily visible and people could quickly see what they had gotten.
Mario Kart: Double Dash was released in 2003 and the HUD was reverted back to the 1996 design for reasons unknown. This meant that the players were added back to the left side. But a speedometer was added to show the player how fast they were going. Many people used this to boast to friends how fast they went. The Time and map were made smaller to allow extra breathing room for the players eyes. If they had stayed the same size it would have taken up a large fraction of the screen.
Mario Kart DS was released in 2005 and has a duel screen HUD. Having two screens allowed the top screen to not be so full of information and allowed the bottom screen to have most of the info. From the top screen they removed the map and time leaving only the real vitals. These were: your placing in the race, the lap you were on and finally the items box to show what item you had received from breaking one of the box scattered around the map. The map was then in turn improved, allowing for more detail and showing where visible pickups were heading. This added another element to the game, to avoid the incoming shells you would look on the map to see where they were coming from.
Mario Kart Wii was released in 2008 and in between those 3 years two arcade games were created allowing the Console HUD to be improved. The HUD was made simpler and some aspects were made either smaller or larger, for example the player’s ranking in the game. The map was enlarged to ensure the player knew where they were going as they ramped up the difficulty of the map. This will be helpful on Rainbow road. Your place in the race also increased in size.
Mario Kart 7 was released in 2011. The HUD over the two games was changed due to the fact that they were each on a different console. This one being on the Wii. This removed the option of more info on the second screen and had to compile all the important info the player needed to be on the main screen but not take up space. The map on this HUD I think is a little too big and took up half of the player’s right side of the screen. Also because it was on a bigger screen they would have had to change the font to look digital and fit with the rest of the game. However the font used may be hard to read for some players due to the concentration of the 3D effect.
Mario Kart 8 was released in 2014 and has a very similar HUD design to the original Mario Kart game. This game was released on the Wii U and would have had two screens. One being the TV and one placed into the remote you held in your hand. The top half (TV) HUD is very simple as most of the important info was put onto the Handheld device which more players looked at. Allowing the players to have more room to see the actual game on the Coins, Lap No. and your place in the race.