engine idle question
 

Hello, I just got my 1976 porsche 911s targa running after recently purchasing it as it had not ran since 2003 due to a broken shift fork. I replaced all the clutch and fork, all tune up parts and fluids. She fired up and seams to run very well. My question is when the motor comes back to idle it stops at about 2000 rpms for a few seconds before it drops down to 950 where it should be. Maybe this is normal ? I checked the throttle cable and it is not getting stuck anywhere , also about 3500 the motor seams to lump a tad bit. Any help would be great! Thanks

Forgot to mention when I disconnect the vacuum line on the distributor the rpm goes from 950 to 2000 that does not seem correct to me . That might be part if the problem or a different problem. Thanks

that is a vacuum retard. not sure exactly what yours is but some had as much as 15 degrees retard. set you r timing for 30 degrees full advance and just use the idle timing as a ref.

there is a decel valve (DV). it is behind the throttle body. it holds the RPM up and lets it come down kind of slowly.

Not clear what you mean by lump. Could you be more specific?