Two years ago I bought an '83 305 that was advertised as low miles on a rebuild. At that time I installed a Summit K1102 cam kit and an Edlebrock Performer manifold along with a Quadrajet. The engine ran pretty good, but I could never get more than 17 inHg in vacuum and it always ran too rich.

This weekend I decided to pull and inspect the plugs, check compression, and work on the timing to see if I could add some more advance for better vacuum. The plugs showed carbon from running rich. Compressions was 165 to 175 except number 3 at 110. So it seems I have a bad rings, burned valve, flat cam lobe, or (I did run through a cam breakin procedure)? I forgot to shoot some oil in the cylinder and test again. I'll do that this weekend.

Please don't diss the 305's, I know all the arguments and happen to like the 305's. They have all the power I need for my purpose.

I have wanted to change things up for a while now so this might be a good opportunity. I hate flat tappet cams. I have removed several cams with flat lobes. This morning along came an add for an '89 305 TBI motor with 140k miles. I can get it complete with the ECU and harness (I really want a TBI for personal reasons). I know the TBI engines suck on HP because of the swirl port heads.

Questions. On the '89 motor.

1. Could I swap my current 416 heads onto it (assuming no burnt valve)? How much effort would it be? Same push rods, etc? Have to drill the intake center bolt holes? Will it make a big difference or be a waste of time?

2. I don't have to pass smog so can I delete stuff like the air pump, etc. What will that do to the ECU? Would I need to burn a new chip?

Thanks

 

I don't really see it being worth anything going from one 305 head to another. What year and application is this anyways?

 

416 heads are not amazing, but they are better than swirlport heads by a huge margin.

mw66nova did very low 12's with a 280H cam and 416 heads on a 305. It was over 10.0:1 compression with a double pumper and had super short gears and a very loose stall, etc... but the heads are capable of good power for sure.