My new carb spacer! Edelbrock 1405 1406 4-barrel carburetor. What kind of spacer? OPEN or 4-hole?

What is the best spacer for my engine?

What is the best spacer for my engine setup is something I needed to address while I had my Edelbrock 600 CFM 1405 off my SBC 350. I put an open square on it years ago when I built the engine so I don't really know what it runs like with the 4-Bore carb spacer. The original spacer is wood and 1/2 an inch tall. 1/2" is all that will clear the hood so I didn't need to contemplate the height of the carburetor spacer.

In my recent research, I have found the prevailing opinion that four holes is needed if you are running a dual plenum intake manifold like any of the performer RPM series intakes from Edelbrock. I run the air gap. When I had it on the original 305, the carb (1406 back then) was bolted straight to the intake. In my mind, it only makes sense because the 4 hole spacer is just replicating the way the carb would sit without a spacer.

I almost thought about not running a spacer and saying screw it because people be making power without them and the AirGap RPM has a pretty big volume under the carb base for atomization and what/not to occur. However, I do like how the carb is isolated thermally to a degree (no pun intended) from the hot-ass engine. So I decided to go with the one in the video.

Tell me what you think? What are you running and what's your logic?

Be sure to check out the rest of the videos in this carb series to follow or catch up on the project. I am rebuilding, Jetting, and tuning a 1405 carb. The steps and parts are pretty similar between all the older school square body edelbrock carbs like 1406 and up to 1407 & 1411

Links to the spacer and the car are below along with other parts to do the whole project!

Clicking on them actually helps me even if you don't buy them! Just use my Amazon links as a shoppers guide!

[AP-wtyh]

I have a 1405 om a 318 LA Mopar. Having issues to start the engine after it's warm, not right when it's off but like 20 minutes later, so I'm going to try with a 1 inch spacer, have plenty of room since it's a jeep CJ-7 '82. Hope this helps with the heat and vapor lock (already put gas filter with return line).

[jordanparker]

Thanks man! I was wondering about this swapped from a Holley 600 to a Eldebrock 1405 had a square spacer for the Holley and out back on with Eldebrock seems to not run right will swap for 4 hole!

[bigjimbo]

i just ordered that spacer for a 58 chevy 283 engine i have in my jeep, have a edelbrock 1901 avs2 carb on it, when engine gets warm and i shut it off after about ten minutes its hard to start, hope this insulator works