So I was listening to a podcast (Adam Carolla's Carcast) and they had Steve Dinan on as a guest. In case you don't know who he is, he is a BMW builder, kinda like Roush for Ford etc. But he was explaining how he builds race engines for a specific circuit where the engines have to be naturally aspirated, and he said he still runs a small supercharger, but not to force air into the combustion chambers, but to put the crankcase in a vacuum! He said by doing this he can take out the oil scraping ring (the second ring) on the pistons because the oil is sucked down instead of being scraped down, and so there is less friction, also the piston can be shorter obviously so less weight and better revv ups, and longer rods etc, and you now dont have to push the air out of the way as the piston returns downward, and it all roughly translates to 35 HP in a BMW V8 after the parasitic loss from the blower is subtracted out, and that is still with not putting the sucked out air into the cylinders!
I was really curious what this would do to a bike engine, especially our older bikes. 1) could our engines take that negative pressure without cracking, and 2) would it help enough to be noticeable?
Just wanted some reactions to the idea as I had never heard of it before.
