Thread: HELP! Edelbrock 1406 tuning.

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Okay, please treat me like a total moron please. I had to replace my lifters in my motor at the dorm parking lot and i removed my distributor and carb and intake. now I need to retune my carb because its running WAY too rich. She's smoking bad but not to where she's stumbling. I can still stomp the gas and she goes nuts. Its just a 355 chevy with an intake and 268 duration cam. nothing wild. so please. please.


someone tell me what the damn screws are on the front of the carburator and how to properly tune the damn thing. or just give me some moron-information.

And don't tell me to read the manual because all those .00234098029 numbers don't make a damn bit of sense to me.

Crowbie
Your questions are common for those learning. Why did you have to replace the lifters? Did you remove the cam when you did so?

A couple of questions to zero in on the problems:

If you removed the cam, did you align the timing marks on the chain/gears? If you say "huh?" then there may be a problem.

Did you re time the engine after you replaced the distributor? If you say "huh?" we may have a problem

Did you adjust the valves before you fired the engine? If you say "huh?" we may have a problem

Did you warm the engine and reset the valves? If you say "huh?' we may have a problem

Did you turn any of the screws on the carb? If you say "huh?'...
you get the idea.

Give us some more clues......

Had to replace my lifters because one collapsed on me, but it had only about 4 minutes of time running in my car before i was able to park the car and shut it off. I then replaced all the lifters because it only made sense to not throw in one new one and have old ones that had been seated to each other.

That probably was the dumbest thing i did. I should have just replaced one lifter right? No i did not take the camshaft out.

I did reset the timing to 10 degrees btdc. I did this by taking the cap off and bumping the motor over until i could feel the piston at the top in cylinder #1.

I have the valves almost adjusted right now. One of them clacks slightly. I need to go back and re-adjust that one.

I did play with the carburator some, I set it until the exhaust wasn't black anymore. (about 1.5 full rotations of the screws from all the way closed clockwise.) I think I may be running too lean.

Is there anything that I'm doing wrong here?

ok... so far sounds good... get those valves adjusted all the way before dinking with the carb.... cause thats going to change things.... replacing all the lifters... decent idea... the only thing i might have reccomended is changing the cam... old cam new lifters... they haven't worn to each other so the cam will probably wear out faster now, but not neccisarily, it all depends.... but once you get those valves adjusted i'm betting you'll have a lot less problems with getting that carb adjusted...

Once you get the timing right try this:

IDLE MIXTURE

The Edelbrock Performer Series carburetor has conventional Idle Mixture Screws (IMS) that provide a leaner A/F when turned clockwise and richer A/F when turned counter clockwise. The idle air flow is controlled by a conventional screw that opens the Primary Throttles. The following procedure should be used to set the idle mixture and speeds.
1. Fully warm engine and ensure choke is fully open.

2. Air cleaner in place.

3. Set desired speed with the air screw.

4. Adjust the IMS on ONE side to get the maximum possible RPM. Do not go rich beyond the maximum speed point.

5. If the above changed the idle speed more than 40 RPM, then readjust the speed.

6. Adjust the side OPPOSITE of that in Step 4 to get maximum RPM.

7. Reset the speed.

8. Carefully trim each IMS to again get the maximum idle RPM.

9. Go leaner just enough to get a 20 RPM drop in speed.

10. Reset the speed to the desired RPM.

11. This is a Lean-Best Idle Set. Setting richer than this will not improve idle quality or performance, but could tend to foul plugs.


This is from the online manual: http://www.edelbrock.com/automotive/eps_sect2.html

I should have mentioned this motor has less than 5,000 miles since last summer. I try not to drive much because of gas prices but when i do drive. Look out!

why a failed lifter? probably just bad parts for all i know. I built it with someone who's built 20+ small block chevy's.

edit:


why couldn't you just link me to this page i finally found?

http://neptune.spacebears.com/cars/stories/carb.html
sure i don't have a mopar but damn. that would have been simple and informative to me.