I have made this box vehicle in blender its a WIP but for my first blender car i think its good. Any suggestions on how to upgrade it some more?
Looks VERY basic right now. I'm not sure I can give very many suggestions since I'm not really sure where you're going to go with this. Just try and get some help from others and learn more about modeling.
No i am going to edit the actual car itself im planing on putting a spoiler in the back. Maybe even a detailed exaust system. P.s I used a tutorial to make the car. I made it myself its just i used the tutorial and i will edit it http://en.wikibooks.org/wiki/Wings_3D/Tutorials/Box_modeling_a_car_with_all_Quad_topography
It is a box with 2 smaller boxes cut from it. By no means do I want to be disrespectful, but I don't think it can really be labelled "good". Barely went beyond step 4 of the tutorial you posted, and you appear to have constructed your car from multiple overlapping objects which you absolutely do not do, nor does the guide say to do that. Another point is that the guide isn't for blender. But that doesnt matter really as it doesnt use any modeller specific tools.
I think it looks promising, Most people don't get past deleting the cube in blender, but if i were you id try following this guide instead: Its very easy to get caught up trying to find a tutorial to model a car when quite frankly its much better using a tutorial to model say a wheel or a mug first, the skills are transferable and you will learn much quicker as arying a car for your first ever model is like trying to walk before you can run! The reason i chose that guide it because wheels are a good place to start in modelling, the are fairly simple, but also modelled using planar modelling (what should always be used in games) this is where a single 2d square is made, and is added to and edited to create a model. You will get the idea by following the tutorial. Do't be put of quickly either, you will not learn to model overnight but spend a year or two modelling and you will become pretty good
I hate to sound bad, but the objects don't even fit together on the car, I suggest that you look up some blender tutorials and start again on a new car.