I have a 1991 Dakota auto that I swapped out the LA 318 with the magnum 318. In the swap I had to convert to a carburator swap in a different distributor. It's never really run right. It wants a ton of timing to have any power, so much that it's right on the edge of not being able to crank. If you dial it back even a degree it hesitates and has no power.

Originally I had a used Edelbrock 650 on there that I rebuilt but I just recently put a brand new Holly 600 hoping that was the problem. It really didn't change much other than it does start a little better.

Has an airgap manifold. The distributor is cheap, it's a eBay HEI. I had to remove the stock fuel pump and put in a little electric (me gasket I think.

I'm wondering if anyone has any ideas to get this thing to make the power it should. In certain spots in the mid-range it feels pretty good at a part throttle situation but when you got to WOT it just kind of bogs and seems like it wants more timing actually but I literally can't put another degree in and have it start.

I'm wondering if there some way it's the distributor since the magnum engine had computer controlled timing and this regular vacuum advance distributir I had to put in just can't work correctly with this setup. I'm just out of ideas.

 

What's the centrifugal advance curve look like? What's the vacuum curve look like? Any chance it's the distributor being a crap one?

RwP

 

Try disconnecting the vacuum advance, and see if it runs any better..... Some of them want manifold vacuum, others want ported vacuum. (manifold vacuum goes down as throttle opens wider, ported vacuum goes UP as airflow increases...... You may have TONS of advance at idle, but as vacuum drops, the ignition advance goes away..... robbing you of power.

 

What kind of shape was your engine in when you dropped it in? How many miles on the engine and how did it run in the other truck? Did you do any work to the engine before putting it in?