Oil in Air Filter

it may but quality air cleaners do not affect air low velocity or change tuning of the engine you can get the air flow specs for each air filter by googling the name of the filter and reading the air velocity graphs for each filter brand

Have had a similar problem,turned out to be a blocked filter on the fuel tap .From memory the little bowl undid like a light globe ES push it in and turn 90 degrees

If the air filter is not obstructed and is properly oiled, then it should perform adequately. If not, try using the original filter. If the problem still exists, you will need to adjust the fuel/air mixture screw. Do not forget, there are 2 other adjustments... idle and an adjustment to the diafram when you blip the throttle.
I can give instruction on how to adjust, but you should look that up yourself on the website of the carb maker.

If you have the screaming eagle cover to compare it to it is easier but if not you can cut back the "sides", sometimes leaving the front the original size.

The use of the terms "stage 1" and "stage 2" are rough indications as to the degree of modifications that have been done to a motorcycle. Now, there are two categories of modifications, those that you can see and those that you can't. You can see the exhaust and air filters and see that these are not the stock parts but high performance parts such as your mufflers and air filter. Other components can't be as easily determined what they are. The components are things such as pistons, camshafts, heads, and crankshafts. The only true way to tell the degree of modifications that have been done to a bike is by taking it to a shop and having them run it up on a dynometer that will measure the horsepower and torque that the engine is delivering. A stock engine produces about 50-60 horsepower. If your engine produces 70 hp, it considered "stage 1" Eighty horsepower, "stage 2". Ninety or above, "stage 3".

Ride Safe
Steve

29406-08

If you upgraded the air cleaner, you should have the carb rejetted. A Stage One upgrade also includes freer flowing exhaust, and a updated ignition, if required.

The early 88's have issues with the cam chain tensioners. They can deterioriate prematurly. Check the condition of these around 20k miles

One alternative to the tensioner problem is to update the Cam Support Plate to a HD Screaming Eagle support oplate w/ Hydraulic tensioners.

Another alternative is to look at an updated cam with a gear drive system. Andrews seems to be very popular.

To answer your question...What are you looking to gain from your cam update? HP? Torque? Both can be added with good results with a cam update. This is considered part of Stage 2 upgrades.

Here's a great explanation of the stage upgrades:
http://www.harley-davidsonforums.com/forums/engine/19351-stage-2-upgrade.html

Hope this helps.