I’ve been building a small 2 door sports car for some time now. It is meant to be a cheap (relatively) sports car that can eat corners for breakfast.
The first thing I can notice is that the car has a tendency to oversteer.
This is not super great, although the default setups for MR cars tend to create this kind of situation.
To fix this, make the front sway bar and spring stiffer, so that instead of shooting up at the end, the line goes down.
This should boost your tameness and cornering abilities.
You could also run more camber on all corners, as well as switch to a stickier tire compound.
The other thing I would recommend is maybe switching to the smaller of the two modern supercar bodies. Since the engine you are using is quite small, it should fit easily and help reduce the weight a little. Ignore this if you are already using that body, can be hard to judge from a single picture. 
As for the last tip, I would reccomend raising your engine’s redline a little, as I wouldn’t be surprised if you had a few hundred more RPMs of useful power after you current redline. You reliability is already fairly good so it shouldn’t be much of an issue, and it might let you switch to 6 speed with no reduction in performance, while lowering both the weight and price of your car.
Thanks for the tips, I’ll give them a try when I get back to my computer. I can’t raise the redline to much more without upping the bottom end parts (I went for cheap parts to keep cost down as top speed is secondary). I am using the smaller super car body (in hindsight they do look exactly the same). I’ll take another look at the springs and sway bars (it did not seem to do much the last time I fiddled with them). Thanks
You could shorten the stroke, and increase the bore, which would allow you to rev higher. That’s definitely worth taking a look at. Also, just make the springs and sway bars a lot stiffer, until the yellow line goes down. From there, you can make them softer, until you find a balance you like.
I’d also add that forged internals are fairly cheap, especially for a 4 cylinder engine since you don’t have a lot of them.
It might not be worth it in a cheap car, but for a sports car it can help get a little bit more performance out of your engine.
Also, you might be able to make the car cheaper and lighter with some lower-end interior options.
To take the Lotus Elise as an example, its interior is very similar to the definition of a standard interior within the game, with basic or standard entertainment.
The sport interior option is more the kind of thing you see in italian supercars. It is more prestigious than standard interior, with a similar weight and IIRC better comfort (might be wrong on the comfort though). The main issue is that it is also very expensive.
