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Discussion Starter · #1 ·
I got my motor back from the rebuilder, he added quite a bit of performance stuff: Crane cam, 10.5-1 compression, e-street heads, air gap intake, Edelbrock 1406 600cfm carb. When I got the motor back I put it in and it ran OK. I did not have the time to tweak anything but it ran pretty good as long as I did not let it idle. It would stall if I let it idle.
I just paid some guys to install the Hooker super comp headers, and flow master delta flow 50 series mufflers.
Now it will not start unless I have the gas all the way to the floor, and if I do not run it way high it stalls.
I am pretty much a rookie. I Know it would not be perfect with all this stuff added. What should I tweak first, second, third? Thank you for your time. You guys have been priceless for guys like me doing this for the first time.
Curt
 

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I would take the car to a local chassis dyno and have it tuned.
 

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That's a lot of problems combined. Assuming the cam is installed properly I would start with the timing, once set, tune the carb. Fire (spark) and fuel are number one. The headers and mufflers would have no bearing on the engine running better or worse although it may run a tiny bit leaner due to the less restrictive exhaust. I'm thinking you have a huge vacuum leak because of the terrible idle but evens out at upper revs. Check for vacuum leaks such as the tube going to the power brake booster. Hope I helped you.
 

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Could be the carb is flooding if you have to floor it to start. Read the Edelbrock owners manual if you have it. Any idea what fuel pump is on the engine? The Edelbrock carbs don't like over 5 lbs. of fuel pressure.
 

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Have you spoken with the guy(s) at the shop that did the top end work? I'd want to ask them why the engine does not run. There should be a series of questions like where is the timing (initial and total) set? Where is the vacuum advance hooked up, if it is hooked up? What was done to the carb? How far past zero lash are the lifters preloaded?

You'll need to use process of elimination to determine why it won't idle/run. You need to verify compression in all 8 cylinders, verify that there are no vacuum leaks, verify that you're getting spark to all 8 cylinders, etc.
 

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My first guess is stuck needle/seat or float level too high. Second guess is ignition timing.
 

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Check the plug wires and plugs. Maybe they got hurt when the guys installed the headers. Or you have two switched. Start w/ the easy stuff first in my opinion.

Also I agree with everything else mentioned. Check timing, carb settings, and a vacuum leak. Can of CRC brake cleaner method works for the vac leak check.

Oh, other than your comment about it not being perfect with all this added. Frankly as long as you were reasonable w/ the cam you selected and everything was installed correctly that sounds like a rather nice list of parts for a 327.
 

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Check the plug wires and plugs. Maybe they got hurt when the guys installed the headers. Or you have two switched. Start w/ the easy stuff first in my opinion.

Also I agree with everything else mentioned. Check timing, carb settings, and a vacuum leak. Can of CRC brake cleaner method works for the vac leak check.

Oh, other than your comment about it not being perfect with all this added. Frankly as long as you were reasonable w/ the cam you selected and everything was installed correctly that sounds like a rather nice list of parts for a 327.
X2, Never even thought of that,,, I am betting his firing order is mixed up also. That can cause everything mentioned. Bad idle especially when it worsened after the header install. Might have been wrong before the headers, then messed up worse by the installers.
 

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Suggest starting with basics.

Verify that the spark plug wires are in the right firing order.

Check the base ignition timing. Make sure the mech advance is working.

Check for vacuum leaks. Make sure there is a vacuum cap on all of the unused vac inlets on the carb. I have run an Edelbrock 1406 for seven years on the 350 in the 66. Only big issue was when I let the carb sit in the trunk for six months and dry with gas in it. It started but would not idle. Removing the top and cleaning all the passages, jets, etc fixed it.

With timing and ignition set, no vacuum leaks, try setting the curb idle. When it has a stable idle, adjust the mixture screws to max vacuum or to the highest idle speed. Then go back to set curb idle.
 

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Peer into the carb while the engine is idling and check for fuel dribbling into the venturis (stuck needle/seat and/or high float level).
 

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Discussion Starter · #14 ·
Check the plug wires and plugs. Maybe they got hurt when the guys installed the headers. Or you have two switched. Start w/ the easy stuff first in my opinion.

Also I agree with everything else mentioned. Check timing, carb settings, and a vacuum leak. Can of CRC brake cleaner method works for the vac leak check.

Oh, other than your comment about it not being perfect with all this added. Frankly as long as you were reasonable w/ the cam you selected and everything was installed correctly that sounds like a rather nice list of parts for a 327.
Can you elaborate on the CRC brake cleaner and vacuum leaks? Go around the intake perimeter and carb base and spray a little bit? What should I expect? All the outlets on the carb and intake are either plugged or connected to the advance unit, the modulator valvbe, or the PCV.
Thanks
 

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Discussion Starter · #15 ·
Suggest starting with basics.

Verify that the spark plug wires are in the right firing order.

Check the base ignition timing. Make sure the mech advance is working.

Check for vacuum leaks. Make sure there is a vacuum cap on all of the unused vac inlets on the carb. I have run an Edelbrock 1406 for seven years on the 350 in the 66. Only big issue was when I let the carb sit in the trunk for six months and dry with gas in it. It started but would not idle. Removing the top and cleaning all the passages, jets, etc fixed it.

With timing and ignition set, no vacuum leaks, try setting the curb idle. When it has a stable idle, adjust the mixture screws to max vacuum or to the highest idle speed. Then go back to set curb idle.
What do you mean by curb idle?
"When it has a stable idle, adjust the mixture screws to max vacuum or to the highest idle speed. Then go back to set curb idle."
Thanks
 

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Curb idle means the engines idle speed when it is warmed up and in park/neutral.

If the idle is set at 700 RPM's and then you make adjustments to the timing or carb (like mixture screws) the idle speed will change so you must then re-set the curb idle speed.

Any idea what the specifications of the new cam are?
 

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Of course to check the base timing you would need to first disconnect the vacuum advance on the distributor and plug the hose, then you can check the initial timing and total mechanical advance with a timing light.

Firing order is 18436572, make sure the distributor isn't installed a tooth off etc.
 

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If it starts right up after sitting all night but is hard to start after sitting for short periods your fuel pressure is too high. Stock pumps can sometimes send 9 and your 1406 needs 5.
 
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