Brad and Deb's 1985 Daytona Shelby Z
How do you make a 4 cylinder whip V8's twice it's size?
This is not a case study or put down article. Frankly we respect any and every vehicle made - - but sometimes people get the attitude that only one specific car/make/model is "GOD" - - and we love to put those people in their place.
How do you generate close to 2 horsepower per cubic inch?
Efficiency . . . simple as that, and this little device allows that - - the exhaust driven turbocharger.
Basically - - (sorry, some people don't know what this wonder is) a turbo is two wheels spinning on bearings. One wheel is the exhaust side and the other is the compressor wheel. The exhaust gases spin the wheel on the exhaust side and that spins the compressor wheel (they're on the same shaft). The compressor side sucks in air and compresses it into the intercooler or intake manifold. In the case of my Daytona - it goes into the intercooler. See, compressing the air beats it up - - all those air molecules bouncing into one another and being squeezed together. This causes the air to heat up - - thus lowering the density of oxygen. (Hotter air = less oxygen molecules given the same volume.) The intercooler cools the air down allowing more oxygen molecules (denser mixture) to be fed to the intake manifold. This allows the car to run more boost - - without going into detonation.
There are a few other things to consider. To make 2 horsepower per cubic inch - - the engine has to be meticulously prepared. Not only to allow for that kind of stress, but also to shave all the loss you can. That requires a balanced system, with the whole picture being taken into account. Boosted cars can experience problems with head gaskets - - this is because you are stuffing more air/fuel into the cylinder and generating a much more potent explosion. That explosion raises the cylinder pressures - - hence making more horsepower, but that also can cause problems where the head (with the valves) and the block (with the piston) come together. If the head gasket or head bolts are of inferior quality, the head can seep pressure into the waterjacket. This will cause a dramatic loss of power and eventual problems. To combat this, my Daytona uses a custom ARP head stud kit. These are the same ones used on Top Fuel HEMI motors. They are essentially bullet proof - and are one of four sets in existance. (At $200/set!) The head gasket is a McCord Perma-Torque. The block was honed with a deck plate during assembly. This keeps the cylinders torqued like they have the head already attached while they are bored.
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