OK guys,
So you will understand I have built alcohol engines for 1/4 migets,
Turbo drag bilkes, and cars. Typically you will up the compression to around
14:1 as just a start. For a piston engine that means a different piston and
usually rod to handle it. Cams need to be optimised for alcohol, and often you
will do a different valve seat. (thinner dur to cooling effect of alcohol) Then
comes the induction system, even with injection systems I changed every o-ring
to one KNOWN compatible with alcohol. If you ar running a carburator you need
brass (not plastic) floats and need to be sure every seal starting with the
float needle is compatible. If you are not running a stainless steel exhaust
system and muffler you better get one. One of the combustion byproducts of
alcohol is formaldhyde, I'm not sure if this is what attacks the exhaust system
or just the water generated does it but the oxidation is aggressive. Usually we
would remove the plugs after the race and squirt top cylinder lube like Marvel
Mystery Oil in the cylinder and turn the engine a few times to prevent rust
prior to the next time we started the engine. Other than that I hardly ever
touched anything except the jetting. :-)
By the way Ed I can guess how the specs on the Saab happen. If setup for
alcohol it runs fine, (on alcohol), when running gas it tries to detonate but
the knock sensors kick back the timing and run the system open loop rich to keep
the temp down. There would be the reason for poorer power and mileage.
Bill Jepson