A real simple thing you can do to wake up your 6 is to replace the 1bbl with one from a 250. Also, get rid of the traverse muffler and replace it with something like a Dynomax Turbo and use a V8 right side of a dual exhaust tail pipe.
Also look at the distributor. The Pertronix is a cheap upgrade, but make sure you check out your vacuum advance. They go bad and you don't notice it and and lose power. You can upgrade to a Duraspark electronic unit as well. Also consider a new coil, the original one has probably pretty weak at this point.
An electric fan will help.
From there, you can replace the head with one from a later 200/250. They have a larger intake and valves. A port divider in addition to a good 3-angle valve job and header make a difference.
Then, you can move onto stuff like a rebuild with a new Clifford or Comp cam, roller-tipped rockers, etc..
Bottom line, you can trick out a 6 following the same rules the V8 guys do, but in the end, it's still a 6. (I love mine and will never get rid of it).
Consider the fact that in original trim, your motor only made about 85 Hp. The 120 rating was almost made up, but not quite. That number is based on numbers taken on motoros with no pumps, accessories, fans, aircleaners, exhaust, on really good fuel, cool air, etc. In 'real world' it's only 85Hp. Don't worry, it's the same story with the V8s well.
I6's are fun because they are torquey and can rev to the moon. They have a 7 main bottom end that is virtually indestructible. The main problem with them is the integral head. However, it's not really a problem if you own a SawZall and are a little creative.
A good rebuild of your motor, keeping it on pump gas and streetable, can get you somewhere around 170 Hp, that's double what it is now, and the motor is far lighter than a V8. There are quite a few people working on turbo setups for them which whould really wake up the motor.
As far as the C4 goes, that's it, your stuck with it. You can upgrade to a T-5 if you want to switch to a manual. On the other end, I've got some drawings done up to be able to adapt the V8 AOD to a 200, but I've got some many other things going on right now, it's on the back burner.
Al
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