[Shotimes] BB lust

[jfmcrr@sbcglobal.net]

>I really don't believe that any wedge-type head is better than a
>central-plug "hemi" or other symmetrical combustion chamber. Just way too
>many compromises. Super high octane fuel, as well as 40+ degree timing
>advance were things that wedge heads needed, as well as stuff like indexed
>spark plugs.


         Let's see...   how much overlap can you get out of a hemi 
motor?  Can you get good compression and a fast burn combustion chamber 
combination out of a motor without a domed piston?  The hemi is a fabulous 
motor for nitro,  4:1 static compression and huge boosts.  With a flat 
piston, it has THE minimum surface area combustion chamber for running hand 
grenade motors.  But when you have to rely on atmospheric pressure to 
charge the cylinder,  you need 4 or five valves,  intake tuning, exhaust 
tuning,  squish areas,  compact combustion chambers,  high 
compression,  and valve overlap.  Hemi's can manage two out of seven.  The 
Keith Duckworth designed Cosworth motors of the 60's relegated hemi's to 
history as high output to displacement N/A motors.



                                                 Joe Facer
                                                 AFM 237