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Hi all. I have just put a cam into my 361 and while it was out i refreshed the heads, new intake and 600 cfm carb. I got the cam in and it was all lined up correctly (I even took a pic just in case i second guessed myself and went to pull it all apart). I thought i had done everything right but now when i start it it wont idle. It will run over about 2000rpm as i run the cam in ok but under that i have to keep "squirting"the fuel to keep it running. I have all the vacuum ports that are not needed blocked off, the manifold is sealed well and everything looks spot on!
I was confused when i went to put the plug leads on as they were in the wrong order from when i took them off, but I have seen 3 different versions of the way the pots are numbered. I have gone with what is on this site...front of the motor and the right side as you're looking at it and connected the leads accordingly.
What would make it do this? Have I put the distributor in wrong? Maybe a tooth out on the cam?
It is frustrating me as i thought i had done this right and double checked everything.
BTW, the carb is a new edlebrock and they come from the factory set up.

Thanks in advance.
Val.
 

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For starters, what cam did you install?

Some cams don't like the non-adjustable rocker arms after they are installed, basically the pushrod length is thrown off, either too short or too long, not opening the valves enough or leaving them open and bleeding the cylinder pressure off too fast. Were the heads shaved at all?

A carb out of the box is truthfully impossible, too many applications. Start with the two needles, turned all the way in gently to bottom them out and turn them out 1.5 turns each. We can tune from there. Double check the firing order 1-8-4-3-6-5-7-2, then check the timing. Disconnect the vacuum advance and plug it off to start with, Double check any vacuum leaks at front and back/base of the carb that it is sealed, including carb to manifold.
 

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I built a 361 as well. Had a similar issue. Turns out that the rocker shafts had to be shimmed up to accommodate the new cam. When it idled, it had a mild "Hiss" sound. Dana nailed the problem, I'm thinking.
 

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What did you take a pic of? You are supposed to degree camshafts with a degree wheel, not take pictures of them. At the very least you're supposed to line the marks on the timing gears up and you should be fine. No pictures needed there.

If this is a radical cam with long overlap/duration, especially from what you had before, your carburetor will not idle correctly. Is this a long duration cam with a lot of overlap? If so, check to see where your idle screw is at. Do you have to back it in a lot further now to keep it running? if so, you're not running off the idle circuit.

Assuming you did the cam install correctly and it was broken in correctly (no wiped lobes or lifters), and no vacuum leaks, I suspect the carb is not calibrated for this cam. Check your timing and make sure it's where it's supposed to be, then look at the carb. What kind of carb do you have?
 

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Hi. Greg here from SS/AFX.

All above suggestions are spot on.
\
What are cam specs? If cam is not over 230 [email protected] duration, you are ok so far as size goes.

Next, check vacume at idle. Anything less than 13" in gear can cause poor idling.

There is a good chance that rockers shafts will need to be shimmed up to accommodate larger base circle on cam, if vacuum is low with above cam spec. Mancini racing or 440 source have these.
 
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