new to me 68 Barracuda Conv, sluggish 318
The second pic below is how it is now, which seems wrong because the linkage should be rest at the back towards the firewall at idle right?
Get yourself a '68 shop manual. It has the illustrations and procedures. There's nothing like reading info from the original source.
Also, a lot of material is covered in the Master Technician's Service Conference. So that's another place to look.
Master Technician Service Conference - Chrysler's Training for Mechanics
Upshifts at light throttle will occur at relatively low speeds
Upshifts at full throttle should occur at relatively high speeds.
Details of the expected ranges are in the service manual.
Kickdown into a lower gear on a '68 torqueflite. IIRC part throttle kickdown is much later. '68 will only kickdown near full throttle.
Spark plug wires: Take that tape off!!! Wires need to be seperated to minimize firing issues. Also try not to run them parallel for long distance.
Upper radiator hose: Not as critical but the corrogated ones create turbulance and resistance.
Sluggish response: Lots of possible contributors. It may have more power but not as much torque as a stock engine. Regardless, try to tune what you have. being hot rodded, tuning can not rely on the factory specs. However they do form a decent baseline to work from on a mildly reworked engine. Begin with initial timing. You will need a tachometer that reads decently at low rpms and a timing light. A factory 68 318 would have initial around 5* BTC at 600 or 650 rpm. With the loss of compression due to the heads and cam, the combustion will take longer to burn at idle. So your engine will almost certainly like more initial timing, say 10 to 12 (or more) at 650 rpm. Measure what it is, go from there with small changes. That's what tuning a hot rod requires. Lots of systematic experiments.