D
Deleted member 12676
Guest
Here's my take on it:
With a piston port intake some air/fuel is pushed back out of the crankcase towards the carb at any lower than peak rpm (which is where a piston port intake functions best due to the inertia of the intake charge). A turbocharger would prevent some of that blowback which would increase the charge that gets transfered up into the cylinder. That would result in some power gain although it may double the pollution of unburnt gas.
With a reed valve intake the turbo would increase the amount of intake charge at all rpm giving a power boost throughout the rev range. also the pollution.
Some people say it would only increase the pollution. I don't think so. For one, the volume of air/fuel transferred into the combustion chamber is normally about 80% of the available volume at maximum (depending on rpm). Increasing the volume that gets transferred increases that percentage for more power. What fuel is lost out the exhaust pipe is not "extra" but what short circuits from the transfer area to the exhaust port. The more the transfer ports aim the intake charge back towards the rear of the cylinder, the less charge gets short circuited. Doing that on these engines by placement of JBWeld at the front sides of the ports nets a power increase every time because the transfer port design is so bad. It would definitely have to be done with use of a turbo.
With a piston port intake some air/fuel is pushed back out of the crankcase towards the carb at any lower than peak rpm (which is where a piston port intake functions best due to the inertia of the intake charge). A turbocharger would prevent some of that blowback which would increase the charge that gets transfered up into the cylinder. That would result in some power gain although it may double the pollution of unburnt gas.
With a reed valve intake the turbo would increase the amount of intake charge at all rpm giving a power boost throughout the rev range. also the pollution.
Some people say it would only increase the pollution. I don't think so. For one, the volume of air/fuel transferred into the combustion chamber is normally about 80% of the available volume at maximum (depending on rpm). Increasing the volume that gets transferred increases that percentage for more power. What fuel is lost out the exhaust pipe is not "extra" but what short circuits from the transfer area to the exhaust port. The more the transfer ports aim the intake charge back towards the rear of the cylinder, the less charge gets short circuited. Doing that on these engines by placement of JBWeld at the front sides of the ports nets a power increase every time because the transfer port design is so bad. It would definitely have to be done with use of a turbo.
