Is there a proper order to tuning a edelbrock 1405?

I've been woundering what is the best/most effective way to tune a edelbrock 1405 carb? sents just about everything is affected by everything else, is there a proper order in which to do it? I tuned my carb several years ago but lately I've been wanting to revisit the situation and do it right. I'm thinking step one would be the step-up spring but I'm not 100% sure of that. I'm running a Comp cams Magnum 280H so there probably isn't much vacuum. I do have a O2 sensor and gauge but it almost always reads rich except when I'm slowly decelerating but still have my foot on the gas (letting off the gas?) than it reads ideal to lean and thats the only time. I'd appreciate any and all input. thank you.

 

http://www.edelbrock.com/automotive_new/misc/tech_center/install/index.shtml should have the info you need.

 

I've read it over afew times... I'm just getting confused by the section on springs for one thing. just for abit of clarification the vacuum springs are numbered to "step-up" when the vacuum drops to the indicated/specified " number correct?

 

Yep, when under a load, the vacuum drops, causing the metering rod to lift to the smaller diameter step. With a vacuum gauge you can get an idea of when you need more fuel, and adjust the spring to meet the need.

 

I also assume you have a narrow band o2 sensor, if you really want to tune it get rid of that thing and get a wide band. Them narrow bands are nothing more than flashing lights anywhere except idle. And that I always tune with a vaccum gauge anyway.

 

Step by step:

1. Remove the Edelbrock carb.

2. Place on shelf (or in front of door, on top of paper stack, on end of rope opposite the boat).

3. Buy Holley carb and install.

Sorry I'm no help....

 

LOL that was going to be my reply at first, but some people like them over holley to each there own.

 

That's exactly what I did....

 

I've heard the same thing about Holley carbs...

 

As long as it is replaced with a Holley it will be OK
Tuning the Edelbrock is fairly straight forward. Just be sure to start with the right spring.

 

I'm currently on the second to lightest spring in my tuning kit and will install the lightest one tomarrow and see where I'm at.

 

So many of us had the exact same thought.

Autolite 4100 is a nice carb as well.

 

I did have a holley at one point but the baseplate broke during install so I sent it back to get it fixed, got it back, and sold it on craigslist awhile back before I broke it again.

 

LOL. Actually I think you were a big help.

 

All Holley edelbrock argueing aside, David I STRONGLY recomend either you get a wideband o2 set up or some dyno time to REALLY see whats going on with your air/fuel ratio.

You really are pissing in the wind with a narrow band sensor and trying tune off of that. The curve is SO quick on a narrow band its way to hard when it always is either rich or lean. And thats just the nature of a narrow band gauge.

Two options I would give you is either an AEM wideband sensor and gauge installed, or head over to AZ Dyno down by your work. Great guys!

How I do it is set base timming, adjust with vacuum gauge for the idle curcuit, set Idle RPM, than do part throttle light loads and read plugs, adjust timing if need be, then go heavy loads part throttle and again pull plug and look. and keep working your way up the ladder. If you adjust timing advance or base start over on your loads testing again.

After all is said and done I pay for dyno time to make sure I am close, and adjust if need be on rollers.

With wideband I ussually skip the dyno and just go to track and adjust from there for timeslips.

If your REAlLY going after fuel effeciency start thinking fuel injection. A whole lot easier and less time consuming.

Another great fuel effeciency tool is a vaccum gauge in your cabin, look at it as a fuel effeciency gauge.

Also remember its a whole package not just the carb for economy.
weight
gears
tires
tire pressure
accesories running
cam timing
spark timing
aerodynamics
most important one your driving style