Ok, I got all excited when I found out I wouldn't have to swap engines just to get to an automatic tranny! I dedided to update the '67 250 with a new carb (old one was beyond rebuild) and went with HEI ignition...neither of which I haven't done before, only it was on v8 engines.
Symptoms before the upgrade:
slight miss felt/heard at idle.
strong acceleration albeit with some smoke from the pipe!
recently gasoline started dripping from the bushings around the throttle-plate shaft.
List of parts changed: (from autozone)
Holley reman rochester OE carb.
AC r44xls plugs
HEI distributor
cap, rotor, coil, coil cover, plug wires
Symptoms after the 'upgrade'!
HARD ERRATIC miss at idle
severe lack of power on acceleration
when carb is tuned to produce no smoke at idle, the engine bogs when you go to wide open throttle.
when carb is tuned to where the truck DOES smoke some at idle, it doesn't bog nearly as bad.
Timing is currently set at 4 degrees BTDC ('67 specs) When set to specs of engine with HEI, idle is even rougher.
I know I probably should have changed the carb first and verified running condition before proceeding. My thought was 'why take the time to tune the carb, when it'll probably need re-tuned after putting new plugs and hotter ignition?'
I'd like to hear some veteran opinions on whether there's issues with the current setup, or if it's possible that there are engine issues that just manifest bolder with a better fuel/spark system.
True mileage of vehicle unknown. Odometer shows 66k. Truck was owned by county from '67 to '83 when my grandfather bought it for a ranch truck. Something I'm wondering about is possibility of burned valves/worn seats. With being a 'leaded gas' engine, I don't recall my grandfather ever using any type of lead substitute. I've never had an engine with burned valves or bad seats, so I don't know what kind of symptoms that produces.
(will be banging head against wall...once again considering sbc conversion)
