motor update and video

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73dartneedswork

73dartneedswork

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I need some advice on a couple of issues I’m having with my engine idle and timing. I have no idea what I’m doing. This is my first project and I’m learning as I go.

I’m just getting my car back together after an engine swap. I’ve installed a used motor with a new Holley 600 carb. I’m trying to set the curb idle speed so I can set the timing on the car. I can turn the curb idle screw to idle the car down to 800 rpms. When I hook a timing light up, it shows the timing to be way past where it should be. My Haynes manual says the timing on my car should be 2.5 ATDC. When I move the distributor to get the timing to 2.5 ATDC the idle goes back up to around 1700 rpms. Do I need to make other adjustments to the carb?

When I put a vac gauge on the motor, it fluctuates back and forth and is low when the idle is low. I had read this can be from the carb running to rich or to lean. Is this correct or do I have other issues?

A little back ground on the motor; it’s a 318 with around 5,000 miles on a mild to stock spec rebuild. I have headers, 2.5” exhaust, and Performer intake. The bad part, is the motor had been sitting in a garage for 15 years. Also the motor was from a truck, so I had to change the oil pan. Also I swapped timing cover to work with my radiator. Switching timing covers meant that I had to put a new timing mark on the harmonic balancer. Using instructions from this board, I believe I marked the balancer correctly. I also used instructions from this board to properly get the motor to run after sitting for so long.

A couple of other things that are going on with the motor besides the fast idle is I believe I have an exhaust leak and the rockers sound noisy (but again, I really don’t know what I’m doing). I had read that loud rocker noise was common for motors that had set along time. Is that correct?
I'll try to post a video, I'll see if it works.
[ame="http://www.youtube.com/watch?v=2TuCdroZaXw"]YouTube - 146 0029[/ame]
 
Come on guys help this guy out.One thing I see is your kick down linkage is not set right.Are you setting your timing with vacuum advance hook up or plug off? Needle bouncing around can be from a hot cam,vacuum leak,or timing set wrong.
 
Was the carb base set on a bench before you went after the tuning?
Probably be good to start there if you don't know where its at before you start. Once you have that set unplug the vac line on the carb that goes to the distributor and block it so there are no vacuum leaks. Start the car and set your base timing and tune it from there. Really hard to tell what is going on not being there..........

Where are you located at in California?? I am in Murrieta.
 
Is that a used carb or new? It seems like a carb issue or vac leak
 
OK when you advance the timing the engine idles up that sounds normal so can you adjust the idle down from there also sounds like you have exhaust leaks I think
 
first......its hard saying without knowing for sure if your timing tab is in exactly the correct spot.

if your running an eddy carb, normally what I do....is....on the front of the carb are 2 adjustment screws, I will start with the right and turn clockwise until the engine starts to run a little sluggish and then I will turn it counter clockwise one quarter of a turn. and then I will repeat the same process on the other side.

then I would set your timing where you want it and THEN set your idle where you feel comfortable with it.....800 rpm in park would probably be 550-600 rpm in gear....so that in the general ballpark if your running mostly stock....you may want to bump it up just a smidge.

as for the rockers....are they roller rockers and or lifters? are they adjustable rockers or factory bolt and go set up?

could be a number of things, if its adjustable than it could be just that the valve lash isnt set up properly and they could use a bit of tweaking, if its not....it could be worn parts.

could depend on how much oil is in the engine, what viscosity of oil you are using in the engine.

as for the vac gauge.....that can vary from a few things, could be out of tune,timing chain slop could cause it to fluctuate,bad gaskets...and so on.

but I would try getting the timing set in and getting the idle set in a general ball park and then see what you get off the vac gauge.

I havent watched the video yet so Ill check that out.
 
Just noticed its a holley ......Im not as familiar with the tuning process on those so Ill let someone else give a better idea on it.

Im not a fan of holleys because It seems like I have had a ton with blown power valves and stuff....I do however like 670 street avengers!

anyhow, get ahold of member stroker scamp, he knows his carbs!
 
Thanks for the replies.

Mad Dart
Where are you located at in California??
Click to expand...
I'm in Sacramento
Sedanman
Is that a used carb or new? It seems like a carb issue or vac leak
Click to expand...
It's a new carb

Before I started the motor, I primed the oil pump with a drill. When I put the gear for the oil pump and distributor back in the motor, could I have put it in wrong?
 
With the #1 cylinder at top dead center, I pulled my distributor out this morning and looked at the slot in the distributor driveshaft gear. It’s pointing straight ahead. I read that it should be pointing towards the #1 sparkplug hole, or like 11 o’clock. I’m going to move it, and see if this helps.
 
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