Runs Like a 2-stroke

[fast911s]

Just put engine (2.2T, weber 40's, Bursch exhaust) back in car after 5 months of body restoration. Ran fine before I took it out. Took Bursch off, and put on stock muffler modified for 2in - 2out.

Car backfires, misses and feels like its running on 4 cyls until about 2200rpm, then it clears itself and runs great. Replaced points, reset timing (6-34) - no help. Re-jetted carbs from 180air/135fuel to 170air/130 fuel - some improvement and car idles fine, but still bogs under 2200 and massive backfiring when not under load or upon deceleration.

Any thoughts? My next step is to shove a tennis ball up one of the exhaust pipes to see if added backpressure helps.

[jpnovak]

Most likely clogged idle jets and passages caused by the engine sitting. Dried fuel does nasty things. Pull all the jets, blow out passages with carb cleaner and then use your air compressor at about 80psi to clear them. Also check to make sure your float bowl levels are properly set.