Jet Turbo

Note: If your not in the mood to read a scenario-type idea, just skip the first paragraph.

So, you just bought a brand new turbocharged car with direct injection and want to "trick it out" a little. So what do you do? You could get a bigger turbo that provides more boost, but that would sacrifice any low-end torque you once had plus create a higher boost threshold. You can't upgrade the intake, since it's already pre-tuned to provide the best flow for the turbo. You can't change the camshafts since they already have top-of-the-line continuosly variable valve timing. So the only thing that's left is to modify the exhaust. The most obvious solution would be bigger exhaust tubing since the turbochargers provide enough backpressure at any rpm, but you notice a problem. The catalytic converters are also providing backpressure, making a modified exhaust system pointless while also converting usable hydrocarbons into many things (including water, which will be quite corrosive to the turbocharger assembly with time). But wait, why not just remove the converters, the engine has direct injection right? Surely that would make it lean enough to pass any emissions test, just like the european version of the Audi A3? Wrong. Direct injection or not, high performance cars (especially super/turbocharged ones) have rich mixtures when the throttle is fully or mostly open. So what can you do?

In low throttle and lean mixture conditions, there would be a tube that bypasses the turbo and goes into a seperate exhaust pipe. In the main system, there is a tube from the bumper of the car (with a butterfly valve in it) that connects with the exhaust headers and tubing. In that tube, there would be a compressor (like in a gas turbine) to take the air from the front of the tube and compress it into the exhaust flow.

When wide open (or close to wide open) throttle occurs, the butterfly valve opens for the air compressor and the valve for the tube that bypasses the turbo closes. The electric motor (hooked up by a CVT) immediately spools up the compressor to prevent the exhaust gases from flowing out the front of the car. Spark plugs ignite the hydrocarbons and the extra compressed air helps them burn. The exhaust flow plus the added bonus of combusting otherwise wasted hydrocarbons would help the turbo to make more boost than it could otherwise.

Then, when you lift your foot up, the exhaust is immediately re-routed into the bypass tube. The Butterfly valve for the exhaust air inlet closes. The electric motor that is used to spool up the compressor is now acting like a generator (which it can do since it is hooked up via CVT) to slow down the compressor and harness its energy (which will be used to recharge the battery and, in turn, be used to spool up the motor once again). The blow off valve would be hooked up to a sensor which (unlike all current blow off valves) would automatically lean the mixture. The air from the blow off valve is then fed into the compressor to spin the generator a little more and mainly slow down the turbo signifiganty (since in this way it would indirectly be hooked up to the generator). This way when you turn the car off, everything slows down relatively quickly (which is good since when the car is off no oil is getting to the turbocharger).