Negative Pressure Supercharging... righto then

[Mike Gayner]

Have a look at this...
http://www.impulsengine.com/kits/index.shtml

They call it "Negative Pressure Supercharging" and to me it looks like a load of bollocks. There are so many problems with this system I don't know where to begin.

The whole system relies mainly on an extremely innefficient exhaust system to create a negative pressure during scavenging, and then a special cam timing to trap the negative pressure inside the cylinders. Please note that I'm not the one who coined the term "negative pressure" as I'm well aware there is no such thing.

Now first of all, even if you were able to create an intense vacuum inside the combustion chambers, it would be enough to force an extremely small amount of air into the cylinders. Just think about it - the low pressure is created when the piston is very near TDC, meaning the low pressure zone would be very small when compared to the volume of the cylinder at BDC.

Even assuming this low pressure stuff worked, the cam timing would absolutely destroy any power up high in the rev range. Next on the list is the induction system. This is a naturally aspirated engine (despite the title) and relies on a hot air charge to create a faster "explosion" (once again not my words) in the combustion chamber, and a low water temperature (using a flow restrictor and no therostat) to keep combustion temperatures down and reduce pinging. Apparently having a high intake temperature yeilds more power due to the fuel "exploding" much quicker in the cumbustion chamber. What a ridiculous idea.

Thoughts on this "supercharger"? Am I missing something or is this thing just plain stupid?