Changed intake and don't idle?

Myasylum

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Ok , I went from a stock 4bbl intake to an RPM Edelbrock intake and now the car won't idle.
It starts right up but then it dies.. if I keep giving it has it will stay running.
I haven't changed the carb settings or the timing either since it doesn't idle.

Any suggestions?

This is for a 72 - 400 4bbl.
 

Geoff 2

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Put the old intake back on? Just Kidding.
I presume the carb was removed for the swap. Most likely cause is debris got into the fuel line & carb is now flooding.
Here is a trick that might work. If it does ok, if not remove carb to check.
Pinch rubber fuel line with vise grips to prevent fuel getting to the carb. Start engine & keep running until engine quits because out of fuel [ usually 2-5 min ]. Remove vise grips. Floats are now at the bottom of the bowl, allowing for a big gap between needle & seats. Rush of incoming fuel will hopefully dislodge any debris. Poor some fuel down carb bores to start engine & test.
 

MoparLeo

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Proper/safe way to prime carb is to fill the fuel bowls through the vent tubes. Never pour fuel down carb. Sure way to start a fire especially if you get a backfire and have spilled fuel on the outside of the carb.
Always do work on the fuel system outside of your garage. Many people have lost houses/garages over the years with a car fire in the garage.
 

R413

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If it was flooding it would not start right up. Check for vacuum leaks, an open hole for a vacuum fitting. A hose left off, etc.

did it fit the heads OK? Is it leaking at the intake gasket?
 

Myasylum

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I just re torqued the bolts and the last bolt on the driver's side appears to be stripped!
I guess that could be the problem. Any advice on re tapping the head? Stock cast iron.
Also what did you guys use for a gasket for the valley pan? I bought mine as a gasket "kit" which I was told the valley pan was the gasket.
 
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66Satellite47

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The valley pan is the gasket, but it needs some prep to seal well. Either a VERY thin coat of RTV or Prematex spray gasket. But with a stripped bolt, that's the first thing to correct.
 
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Don Frelier

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Does it have power brakes?
Booster vacuum hose connection?
 

Myasylum

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The vacuum hose for the brakes is connected.
 

66Satellite47

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The stripped bolt hole needs to be repaired, either with a heli coil or the next size larger bolt (NOT RECOMMENDED). You can't cure the vacuum leak with a stripped bolt. Plus you will likely have an oil leak at the corner, since you aren't clamping that corner of the tray down.
 

Myasylum

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Thinking about solving the problem with this...

Screenshot_20220619-092315_Chrome.jpg
 

66Satellite47

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The EDE RPM's are a pretty nice head in my opinion. Like all aftermarket the need to be checked by a qualified HP machinist, The valve guides and valve job need to be checked. The EDE RPMs will perform better than any OEM iron head, and most iron heads that are not heavily ported.
 

Myasylum

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I don't even know where a machinist is in my area (Milwaukee). Good thing you said that, I just would have slapped them on.
Temporarily I may just chase the thread down and try a slightly longer bolt.
 

RemCharger

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I don't even know where a machinist is in my area (Milwaukee). Good thing you said that, I just would have slapped them on.
Temporarily I may just chase the thread down and try a slightly longer bolt.
Yes. If you take the valve cover off, you can see the bolt come through to ensure proper engagement.
 

WileERobby

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If $$ isn't a barrier, aluminum heads preferable. Also, if you're running headers, check if the heads are straight or angle plug, there may be interference issues.
 

66Satellite47

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I don't even know where a machinist is in my area (Milwaukee). Good thing you said that, I just would have slapped them on.
Temporarily I may just chase the thread down and try a slightly longer bolt.
Check with the local drag racers with good running Mopars at the track. I'm sure they can tell you who the good local HP shops are. Milwaukee should have quite a few. Go over to the Racers Hangout Forum and ask for advice.
 

Archie Duiker

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I just re torqued the bolts and the last bolt on the driver's side appears to be stripped!
I guess that could be the problem. Any advice on re tapping the head? Stock cast iron.
Also what did you guys use for a gasket for the valley pan? I bought mine as a gasket "kit" which I was told the valley pan was the gasket.
On many aluminum intakes you need to add thin gaskets to the valley pan to get a proper seal (per Edelbrock Performer instructions). I did that when changing from the stock cast iron intake to the Performer on my 383 but found the manifold bolts would not go in properly due to mis-alignment of the holes, so I went with a couple of layers of Permatex Copper Spray-A-Gasket on both sides of the valley pan. That worked well, with no vacuum leaks. If you are not using the EGR you should get the valley pan with the exhaust heat holes blocked off.
 

66Satellite47

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The thin Fel Pro paper gaskets with either the Kopper Kote or Permatex red spray on the valley pan may be a help. You still need to check the alignment and bolt hole position.
 

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